ALBERT

Notes: The corrosion inhibition efficiencies of five different nitrogenous heterocyclic bases 3-amino-1,2,4-triazole (ATA), 2-amino-1,3,4-thiadiazole (ATDA), (p-toly) 1,3,4-triazole (TTA), 3-amino-5-methylmercapto-1,2,4-triazole (AMTA) and 2-aminobenziotriazole (ABA) on carbon steel were investigated in relation to their molecular structure. Corrosion current densities, in the absence and presence of the compounds, were used to assess inhibition performances. The corrosion efficiencies were considered on the basis of their molecular planarity, aromaticity and p-electron donation assumption.

Notes: Advanced crack-resistant coatings based on water dispersion of chlorine-sulpho-polyethylene (CSPE, Hypalon®) vulcanized by Mannich alkalis (MA) water solution were obtained. Application of MA as a CSPE structure component makes it possible to produce a vulcanized net of saturated polymer, and thus to receive ecologically safe impenetrable crack resistant coatings of any substrata (concrete, metal, plastic, etc.). The coatings can be applied in aircraft, automotive, shipbuilding, paint and varnish industries, civil engineering, etc. as a corrosion-resistant material. The optimal coating composition and its mechanical properties have been studied.

Notes: Surfactants are important corrosion inhibitors that are used in different applications. This paper utilizes the recently developed methodology and formulae to predict mild steel corrosion inhibition by alkyl pyridinium chloride and alkyl trimethyl ammonium bromide compounds. By utilizing different surfactants of varying chain lengths in different acidic media and determining the associated corrosion inhibition, the relationship between surfactant concentration, surfactant hydrocarbon chain length, surfactant critical micelle concentration, and corrosion inhibition can be evaluated. The results from this study can be used to improve relevant industrial uses of surfactants for corrosion inhibition.

Notes: Several cyclic hydroxylamines containing hydrophobic substituents were prepared. All these hydroxylamines were tested for corrosion inhibition of carbon steel in 1M HCl at 60°C by gravimetric and electrochemical methods. All compounds showed excellent corrosion inhibition efficiency (IE per cent) in acidic solutions containing 400?ppm of the inhibitors; Inhibitor Efficiencies in the range 66-98 per cent were measured by the gravimetric method. Comparable results were obtained by the electrochemical method using Tafel plots for the IE of some of the selected synthesised compounds.

Notes: A new zinc phosphating bath, which produces coatings at relatively lower temperatures within a reasonable time by using of chemical accelerators has been devised. Improvement of the bath performance by the addition of divalent cations like calcium, manganese and magnesium has been studied. Bath formulation and operating conditions have been optimized by coating weight determinations. Corrosion resistance property of the resultant coatings has been evaluated in 1,000?ppm Cl- by electrochemical methods such as potentiodynamic polarization and impedance measurements. Results of the electrochemical techniques have been complemented by salt spray, humidity and immersion tests. Porosity and roughness of the coatings have also been studied. Results show that the phosphating bath with manganese addition gives good coatings within 30?min. Studies have shown that the corrosion resistance of the resultant coatings are much superior than the conventional coatings.

Notes: In a new build waste incinerator, the waste (refuse derived fuel) was burned on a discontinuous moving grate. Frequent furnace overpressure peaks occurred because of this firing method and as a result, flue gas and fly-ash were pushed out of the boiler and into the building. During the plant start up period, a seal in a water-feed pipeline broke, and a large amount of condensed steam was discharged into the boiler house. Shortly thereafter, very severe corrosion was noticed on the galvanised gangways, steel building components, the boiler aluminium sheeting and on processing lines. A theoretical study of the condensation of the flue gas indicated that sulphuric acid would condense before it reached the external aluminium sheeting and that under normal conditions, dry hydrochloric acid fumes would be removed by the boiler house ventilators. However, the steam leakage had caused the hydrochloric acid to be dissolved in the condensed water and that had resulted in the severe corrosion damage, which had become evident subsequently.

Notes: The inhibition of sweet gas corrosion of carbon steel in high pressure CO2 saturated brine by rosin amine has been studied by weight-loss, electrochemical polarisation and electrochemical impedance spectrum measurements. The results obtained revealed that rosin amine compound is a good inhibitor. The inhibition efficiency increased with the increase of inhibitor concentration. Rosin amine acts mainly as a adsorptive mixed-type inhibitor. The adsorption of the inhibitor on the metal surface in high pressure CO2 saturated brine obey Langmuir isotherm. The adsorption mechanism of inhibitor was both electrostatic-adsorption and chemisorption.

Notes: A variety of bisquaternary ammonium salts was prepared for the first time by reacting N,N,N',N'-tetraallyl-1,6-hexanediamine with allyl chloride, propargyl chloride, benzyl chloride, and 1-bromododecane in excellent yields (〉90 per cent). Inhibition efficiency for different concentrations of the synthesised compounds for the inhibition of corrosion of carbon steel in 1?M HCl exposed for 6?h at 60°C was determined gravimetrically. The bisquaternary salts exhibited excellent inhibition efficiencies (97-99 per cent) in the acidic solution containing 400?ppm of the inhibitor. Comparable results were obtained by the electrochemical method using Tafel plots for the inhibition efficiency of the synthesised compounds. The adsorption of these compounds on carbon steel surface was found to obey Temkin's adsorption isotherm. The work marked the beginning of constituting an important class of new inhibitors containing multiple adsorption centres of positive nitrogens as well as p-donor moieties.

Notes: The spinel NiFe2O4 has been identified as being a potentially successful anti-corrosion ceramic that can be used in aluminium electrolysis under molten salt corrosive conditions (970°C). The evaluation and fabrication processing of NiFe2O4 has been studied in this paper. According to the analysis and comparison of material properties, it has been concluded that fabrication technology for making anti-corrosion electrode material would not be exceptionally difficult and therefore that the material has a strong potential for use in this service.

Notes: The pitting corrosion of copper in chloride solution has been studied using potentiostatic polarisation and surface analysis techniques. X-ray photoelectron spectroscopy (XPS) results enabled conclusions to be drawn about the nature of the film formed in different chloride concentrations. In dilute chloride solutions (C=10-3?M), XPS proved the existence of Cu2O film on the copper surface. It was found that, depending on the chloride content, pitting of copper was evident only after the formation of a protective film of Cu2O. A current-time trend plot showed the onset of fluctuations, which were dependent on the NaCl content. On the other hand, introduction of O2 into the solution during prepolarisation time period increased the current value of the fluctuations at the same concentration of NaCl in comparison with the freely aerated solution. These results, together with the surface analysis, confirm the role of chloride ion on the mechanism of pitting attack on copper metal.

Notes: The sulphidation behaviour of high contraction (HC) and low contraction (LC) chromium plated steel was studied in sulphur with a partial pressure of 1?atm at 1, 3, 5 and 7?h and 0.1 and 0.01?atm at 5?h. The temperature was 600°C throughout the work. It was found that HC and LC chromium plating imparted significant sulphidation resistance to steel. It should be mentioned that by increasing sulphidation time and sulphur partial pressure, the hardness of chromium coating decreased. LC chromium coating had a lower thermal shock resistance than the HC coating. Thus, it was concluded that the HC chromium coating had the better sulphidation resistance.

Notes: In this study, electrochemical parameters were used to evaluate the inhibition effects of molybdate and silicate inhibitors in tap water. With the aid of "grey system" theory, we determine the inhibitive state model of such systems.

Notes: A study was undertaken to investigate the isothermal oxidation behaviour of Ni-Cr binary alloys with 10, 20 and 30?wt per cent Cr exposed in air for 50?h at 1,000°C. Analytical transmission electron microscopy along with light microscopy and X-ray diffraction were used to characterise the oxide scale. It was observed that the scaling behaviour exhibited by the Ni-Cr alloys changes from generally "non-protective" to "protective" as their Cr content increases from 10 to 30?wt per cent. The Ni-10Cr alloy formed a continuous network of NiO leading to scales of high thickness while Ni-30Cr exhibited only a-Cr2O3 at its surface. The Ni-20Cr alloy exhibited all three oxide phases and an intermediate scaling behaviour.

Notes: A kind of novel heterocyclic bisquaternary ammonium salt (MBQA) was successfully synthesised with metronidazole as matrix and dichloroethyl ether as the link agent. Weight loss measurement, potentiodynamic polarisation curves, electrochemical impedance spectroscopy and atomic force microscopy were used to evaluate the corrosion inhibiting performance of MBQA in simulated oilfield water. Experimental data revealed that MBQA acted as an inhibitor in the acidic environment and, furthermore, the compound was a mixed-type inhibitor. It was found that inhibition efficiency increased with an increase in MBQA concentration at different temperatures. The process of inhibition was attributed to the formation of an adsorbed film on the metal surface, which protected the metal against corrosive agents.

Notes: Coatings with outstanding chemical and physical properties can be obtained from two-pack formulations without stoving. The epoxy resin was cured with different amine-based compounds, such as polyamide (PA), the aniline copolymer of triethanolamine titanate and aniline formaldehyde. The thermal resistance properties of the cured films were analysed using the thermo-gravimetric method. This study also examined the effect of coating resistance of 3 per cent sodium chloride solution by means of electrochemical impedance measurements. Coatings that included the epoxy triethanolamine titanate showed superior behaviour, compared to the other two systems tested. This hardener can be recommended instead of using conventional PA and polyamidoamide hardeners for epoxy two-pack systems that are to be used to protect the steel structures from highly corrosive chemical and marine environments.

Notes: The inhibition effects of sodium silicate and polyphosphate on corrosion of carbon steel in a potable water supply have been studied using weight loss, electrochemical impedance and Tafel polarization measurements. In the water supply under test there were sufficient calcium ions, (220?ppm), to form the normal polyphosphates salts, which is a requisite for good protection. It was concluded that the inhibition efficiency of polyphosphate was higher than that of silicate. The synergistic inhibition effects of polyphosphate on the inhibition of silicate were studied. The results illustrated that silicates and polyphosphates can be useful as corrosion inhibitors for reducing the corrosion of carbon steel in potable water supply distribution systems. The optimal concentration for silicate alone was determined to be 11?ppm and for polyphosphate alone was 8?ppm. The optimum ratio of concentration for sodium silicate to sodium polyphosphate was 4?:?3.

Notes: Purpose - To cover the main contributions and developments in solar thermal collectors through focusing on materials, heat transfer characteristics and manufacturing challenges. Design/methodology/approach - A range of published papers and internet research including research work on various solar thermal collectors (flat plate, evacuated tubes, and heat pipe tube) were used. Evaluation of solar collectors performance is critiqued to aid solar technologies make the transition into a specific dominant solar collector. The sources are sorted into sections: finding an academic job, general advice, teaching, research and publishing, tenure and organizations. Findings - Provides information about types of solar thermal collectors, indicating what can be added by using evacuated tube collectors instead of flat plate collectors and what can be added by using heat pipe collectors instead of evacuated tubes. Research limitations/implications - Focusing only on three types of solar thermal collectors (flat plate, evacuated tubes, and heat pipe tube). Practical implications - Useful source of information for consultancy and impartial advice for graduate students planning to do research in solar thermal technologies. Originality/value - This paper fulfils identified information about materials and heat transfer properties of materials and manufacturing challenges of these three solar thermal collectors.

Notes: Purpose - Copper and its alloys are widely used in industries because of their good resistance to corrosion and are often used in cooling water systems. Brass has been widely used for shipboard condensers, power plant condensers and petrochemical heat exchangers. Brass is susceptible to the corrosion process known as dezincification by means of which brass looses its valuable physical and mechanical properties leading to failure of structure. The aim of this investigation was to control the dezincification of brass in 3 per cent NaCl solution using benzotriazole (BTA) derivatives. Design/methodology/approach - BTA derivatives namely 1-hydroxymethylbenzotriazole (HBTA) and N,N-dibenzotriazol-l-ylmethylamine(ABTA) were synthesised and their inhibition behaviour on brass in 3 per cent NaCl solution was investigated by the weight-loss method, potentiodynamic polarisation, electrochemical impedance and solution analysis techniques. The morphology of the brass after corrosion in the presence and absence of the BTA derivatives was examined using scanning electron microscopy (SEM). Findings - Potentiodynamic polarisation studies showed that the BTA derivatives investigated were mixed type inhibitors, inhibiting the corrosion of brass by blocking the active sites of the brass surface. Changes in the impedance parameters (charge transfer resistance and double layer capacitance) were related to the adsorption of BTA derivatives on the brass surface, leading to the formation of a protective film. Solution analysis revealed that the BTA derivatives excellently controlled the corrosion of brass. SEM micrographs showed the formation of compact surface film on the brass surface in the presence of inhibitors, thereby providing better corrosion inhibition. Originality/value - Contributes to research on corrosion protection for copper and its alloys.

Notes: Purpose - To study flow-induced corrosion mechanisms for carbon steel in high velocity flowing seawater and explain corrosive phenomena. Design/methodology/approach - An overall mathematical model for flow-induced corrosion of carbon steel in high velocity flow seawater was established in rotating disk apparatus using both numerical simulation and test methods. By studying the impact of turbulent flow using the kinetic energy of turbulent approach and the effects of the computational near-wall hydrodynamic parameters on corrosion rates, corrosion behaviour and mechanism are discussed here. It is applicable to deeply understand the synergistic effect mechanism of flow-induced corrosion. Findings - It is scientific and reasonable to investigate carbon steel corrosion through correlation of the near-wall hydrodynamic parameters, which can accurately describe the influence of fluid flow on corrosion. The computational corrosion rates obtained by this model are in agreement with measured corrosion data. It is shown that serious flow-induced corrosion is caused by the synergistic effect between corrosion electrochemical factor and hydrodynamic factor. While corrosion electrochemical factor plays a dominant role in flow-induced corrosion. Originality/value - The corrosion kinetics and mechanism of metals in high velocity flowing medium is discussed in this paper. These results will help someone who is interested in flow-induced corrosion to understand in depth the type of issue.

Notes: Purpose - To investigate the influence of an organic corrosion inhibitor on the enhanced dissolution of metal, initiated by AFM tip scratching in corrosive media. Design/methodology/approach - The test solutions were 1.5?M NaCl and 0.01?M HCl. AFM tip scratching experiments were performed for Cu-Ni alloys in solutions with or without 0.005?M dodecylamine. AFM frictional loop tests were also performed to investigate the effect of dodecylamine on the tip-surface frictional interaction. Findings - Enhanced dissolution of Cu-Ni alloy was observed as a result of AFM tip scratching both in NaCl and HCl solutions, and in HCl the effect was more severe than was the case in NaCl. Enhanced dissolution was inhibited markedly by adding 0.005?M dodecylamine to the corrosive media. The results of frictional loop tests indicated that frictional interaction between the tip and the alloy surface was diminished by the adsorption of dodecylamine on the sample surface. The weakening of tip-surface frictional interaction and the elevation of the ionization energy of metal atoms were responsible for the notable inhibition effect of dodecylamine on the accelerated dissolution. Originality/value - In this paper, the influence of an organic corrosion inhibitor on the corrosion of metal induced by outside forces was investigated. This was carried out initially by AFM scratching skill and the inhibition mechanism of dodecylamine on the enhanced dissolution of Cu-Ni alloy initiated by AFM tip scratching.

Notes: Purpose - This paper is concerned with the study of silica fume that arises in tonnage amounts during the manufacture of ferrosilicon alloys; this was done in order to maximize productivity and to create new market for industrial by-product and/or waste material. Design/methodology/approach - The structure and particle shape of silica fume were identified using X-ray diffraction and electron microscope, respectively. Standard methods were used for the identification of chemical analyses, solubility, hydrogen ion concentration, specific gravity, bulking value, oil absorption, chemical resistance and particle size. The characterized and evaluated silica fume was applied in several paint formulations. The physico-mechanical, chemical and corrosion protective properties of the paint films were measured according to standard methods. Findings - The silica fume under investigation was a fine lightweight fluffy amorphous powder. It has a grayish-white color that makes it suitable for use as a filler and extender pigment in a wide variety of different fields of application; its amorphous nature favors safe use from a standpoint of industrial hygiene. It can be used as an economic pigment that possesses suitable values of specific gravity, bulking value and oil absorption. It also is inert, neutral and of an excellent chemical resistance. The material can be used successfully as an extender pigment in different paint formulations; taking into consideration that alkyd resin based paints should not be used in alkaline environments or mixed with basic pigments, or the paint film will deteriorate. Silica fume particles in the pigment mixture may offer a suitable opportunity for the voids formed by the larger particles to be occupied by smaller ones to produce a condition of maximum packing. It can be successfully used with the flaky aluminum or stainless steel anticorrosive pigments to produce a highly efficient corrosion protective film. Originality/value - There is increasing environmental concern with regard to excessive volumes of solid waste hazards accumulation. Silica fume that arises - as a disposal material - in tonnage amounts during the manufacture of ferrosilicon alloys can find a new market in paint industry. It can be used successfully for anticorrosive paints to provide well backed paint films.

Notes: In this investigation, the inhibitory effect of a new synthesised tetra-dentate Schiff-base, bis-(2-hydroxy-1-naphthaldehyde) 1,6-hexadiamine (A1), on the corrosion of carbon steel in 1?M HCl and 0.5?M H2SO4 media solutions was studied using various techniques including electrochemical impedance spectroscopy polarisation curves and weight loss. The new compound was shown to be a very good inhibitor and had better behaviour in 1?M HCl than was the case in 0.5?M H2SO4. Potentiodynamic polarisation tests showed that this inhibitor had both cathodic and anodic action. Changes in Tafel and impedance parameters (Icorr, Rct and Cdl) indicated that the absorbed protective film grows with increasing exposure time and concentration of inhibitor. The maximum inhibition efficiency was approximately 97 per cent and 95 per cent at 100?ppm (A1) in 1?M HCl and 0.5?M H2SO4. The adsorption of this inhibitor on a carbon steel surface in both acidic media followed Langmuir adsorption isotherm behaviour.

Notes: Combustion modifications to minimize NOX emissions have magnified the importance of waterwall corrosion in coal-fired boilers. The physics and chemistry controlling corrosion processes can be highly non-linear and are challenging to describe in terms of their likely overall combustion behavior. This paper describes the application of a multi-point, real time corrosion surveillance system to a large boiler firing high sulfur coal. This technology, incorporating electrochemical sensing and wireless signal transmission, enables combustion engineers and plant operating personnel to make informed decisions regarding the quantitative relationships between operating conditions, NOX emissions, and any resultant extent/magnitude of waterwall corrosion.

Notes: Specimens of 304 stainless steel with various martensite contents were prepared by a low temperature (-70°C) elongation method. Optical microscopy and transmission electron micrography were used to study the phase structure of the samples. A simulated occluded cell (OC) and electrochemical impedance spectroscopy were used to study the chemical and the electrochemical changes within pits on 304 stainless steel containing the different martensite contents. The EIS results showed that the martensite phase decreased not only the solution resistance in pit, but also the polarization resistance value between metal and solution in pit. The composition of the passive film in OC solution was studied by X-ray photoelectron spectroscopy. It was observed that martensite transformation was a very important factor in changing the composition of the passive film. The martensite phase destroyed the integrality and compactness of the passive film. For these reasons, pit propagation in Type 304 stainless steel was accelerated with increasing martensite content.

Notes: Purpose - Aims to study the behaviour of four polycrystalline carbon steels in basic pitting solutions. Design/methodology/approach - Electrochemical investigations were carried out on four steels: Fe.06C, Fe.18C, Fe.22C and Fe.43C. The analysis was made using an X-ray fluorescence apparatus. The performance indicator was the pitting potential, which was obtained through potentiodynamic sweeping. Emphasis was placed on the influence of the pH, chlorine concentration, phase proportions in the steel and the initial electrode surface state. Findings - The results showed that in a solution with a low chlorine concentration, the performance of the steels according to pitting corrosion resistance decreased with the increase in carbon content. By raising the chlorine concentration, the order of performance was inverted gradually, while at a high chlorine concentration, the behaviour of the steels tended to be similar. The interpretation of the results is based on the consideration of cathodic reactions on the level of the cementite phase and the difference in the local chemical properties of the solution. In neutral solutions, pitting potentials were shifted cathodically, but the main observations developed for basic solutions remained valid. Originality/value - Provides further research on pitting corrosion.

Notes: In this work, commercial silver metal contacts welded on top of silver plated brass or brass substrates have been exposed to air rich in NaCl. Scanning electron microscopy and energy dispersive analysis of the exposed contact surfaces were performed to identify the corrosion by-products on top of the silver contacts, suspending wafers, and welding materials. Surface corrosion products were mainly found to consist of small spherules of Cu-Zn or Ag-Cu compounds which cover the surface of the contact proper with low adhesion properties. They mainly originate from the underplating wafer or welding materials. Electrical characterization of the contacting materials was based on dc temperature overheat tests, current switching cycle tests, and energy storage during ac current excitation. The experimental results display that the operating environment is indeed a very significant parameter determining the overall performance of the electrical contacts. New design rules as well as material selection properties may have to be systematically considered to allow for electrochemical induced degradation in saline operating environments.

Notes: The eastern coast of Saudi Arabia has one of the most corrosive environments in the world. Dhahran is therefore an ideal location for the study of atmospheric corrosion. One out of every seven cars in the region is corroded. The atmosphere is contaminated by SO2 and a high concentration of suspended particulate matter (SPM) containing sand, salt and carbon particles, exceeding the World Health Organization (WHO) and Middle East Environmental Protection Agency (MEPA) limits most of the time. Corrosion proceeds in the Dhahran atmosphere at a R.H. as low as 40 per cent. At locations close to the sea (1.5 Km), ß-FeOOH is the major corrosion product and a- and ?-FeOOH with some aluminates, silicates and hydrocarbons the minor products. At a location remote from the sea a- and ?-FeOOH are found to be the major corrosion products as shown by XRD and FTIR spectroscopy. The concentration of hydrogen ions, chloride ions and SO2 appears to control the corrosion process during the initial exposure period up to one year and the adsorption of anions on the corrosion product films in the later period.

Notes: Lamellar micaceous iron oxide paints are successfully employed to provide longlife corrosion protection for metallic structures when exposed to highly aggressive environments. The aim of this work was to formulate and manufacture lamellar micaceous iron oxide paints, able to be used on the protection of steel structures exposed to water. Several formulation and manufacture variables were taken into account. Many paint films fail when they are saturated with moisture and blistering is a common failure because primers usually are not designed to allow the liquid to dissipate back out through the film. Consequently the film can not resist the formation of projections which result in local adhesion loss. For maximum durability, primers must be properly formulated and manufactured. Film permeability, which depends on paint composition (pigment volume concentration) and micaceous iron oxide dispersion time, seems to be the key characteristic controlling subsequent coating performance. Laboratory results indicated that lamellar micaceous iron oxide is a pigment which provides an anticorrosive action by providing a barrier effect. Film permeability must be compatible so as to attain a satisfactory rusting and blistering resistance.

Notes: Nickel alloys are widely used as constructional materials in chemical processing industries. They are very resistant to pitting and crevice corrosion. In the present work, the corrosion behaviour of Monel in phosphoric acid of different concentrations has been studied by weight loss and electrochemical methods. It has been observed from the polarization studies that the passivation range slightly varies with H3PO4 concentration. The nature of the passive film has been investigated using the electrochemical impedance method.

Notes: The susceptibility of 17-4PH and 17-7PH stainless steels to stress corrosion cracking (SCC) is examined in the present investigation. The specimens were tested in the presence of NaCl and NaOH (20%) at 908C and various pH values. The evaluations were carried out using the CERT test, at a speed of 10-6s-1, supplemented by anodic polarisation and electrochemical noise analysis. The main objective was to identify the conditions of both susceptibility and performance of these materials. Fractographic analyses revealed both ductile and brittle fractures. Also, the presence of intergranular cracks was a clear indication of a characteristic anodic dissolution of the material. Nevertheless, the main mechanism for stress corrosion crack propagation was hydrogen embrittlement. From the experimental results, it was concluded that electrochemical noise analysis is a reliable technique for the identification of crack nucleation and growth.

Notes: Shows how observations (1993-1999) and on-site and laboratory measurements (1993-1996) have made it possible to define certain prevalent parameters concerning AC corrosion risks. These are from the evaluation and prevention of AC corrosion risks as practised by Gaz de France.

Notes: Zinc-cobalt alloys have been electrodeposited from a sulphate bath. The effect of process variables, including temperature, time, concentration of cobalt sulfate and current density on the Zn-Co deposition was investigated from kinetic and mechanistic viewpoints. Activation energies, enthalpies and entropies were determined according to Arrhenius and absolute rate theories. The codeposition mechanism of TiO2 with cobalt-zinc in the presence of benzyl triethanol ammonium exthoxylate (BTAE) has been studied. The optimum concentration of the additive was reported. The mechanism of incorporation of TiO2 was suggested and confirmed in view of calculated free energy of adsorption of TiO2. Corrosion resistance of Zn-Co-TiO2 alloy was determined by a salt spray test under most of the plating conditions studied.

Notes: The first major nickel alloy introduced to the industry, about 100 years ago, was a Ni-Cu alloy 400. This alloy is still widely used in a variety of industries and will continue to be used in this current century. Over the past 100 years, especially in the last 50 years, improvements in alloy metallurgy, melting technology, and thermo-mechanical processing, along with a better fundamental understanding of the role of various alloying elements has led to new nickel alloys. These have not only extended the range of usefulness of existing alloys by overcoming their limitations, but are reliable and cost-effective and have opened new areas of applications. This paper briefly describes the various nickel alloy systems developed during the last 100 years and comments on what the future holds for the newer alloys developed in the last 20 years and on the competition faced by these alloys in the new millennium. High-temperature alloys are not discussed in this paper.

Notes: Sodium oleic sulfonate (SOS), polyoxyethylene (20) sorbitan monooleate (Tween 80 or T80) and their mixtures have been studied as acid corrosion inhibitors for mild steel in 1M HCl using adsorption and gravimetric techniques. All the data reveal that the compounds act as inhibitors in the acid environment. The adsorption and inhibition efficiency are discussed as a function of the concentration and the nature of mixing the two surfactants. T80 + aSOS mixtures show a better inhibition effect than SOS + aT80, that increases with the value of aSOS. The interaction and synergism of the investigated mixtures are studied by calculating the interaction parameters (ß) and the degree of synergism (S) from surface tension-concentration and corrosion data. The degree of synergism for T80 + aSOS is higher than that of SOS + aT80. This is believed to be due to the presence of the small amount of the co-surfactant SOS which serves as an anchor molecule for the nonionic molecules.

Notes: The inhibition efficiency of sodium gluconate (SG) in controlling corrosion of carbon steel immersed in the environment containing 60 ppm Cl– has been evaluated in the presence and absence of Zn2+ by weight loss method. SG and Zn2+ show a synergistic effect. The protective film has been analysed by FTIR and fluorescence spectra. The protective film consists of Fe2+-gluconate complex and Zn(OH)2. The film is found to be UV-fluorescent. The IE of the SG-Zn2+ system increases in the presence of Na2SO4; but decreases in the presence of Na2SO3 and also in the presence of N-cetyl-N,N,N-trimethyl ammonium bromide. This study reveals that the transporting phenomenon plays a larger role than the scavenging of dissolved oxygen.

Notes: Poly(styrenesulphonic acid)-doped polyaniline has been synthesised and the influence of this polymeric compound on the inhibition of corrosion of mild steel in 1M HCl has been investigated using weight loss measurements, galvanostatic polarisation studies, electropermeation studies and a.c. impedance measurements. The polymer acts predominantly as an anodic inhibitor. Hydrogen permeation studies and a.c. impedance measurements clearly indicate a very effective performance of the compound as a corrosion inhibitor. The adsorption of the compound on the mild steel surface obeys Temkin's adsorption isotherm.

Notes: Results have been presented of investigations on the effect of the temperature change rate on the critical temperature of pitting corrosion. Investigations of 316L stainless steel have been conducted by cyclic thermometry. An increase has been stated of the critical pitting temperature with increase of the temperature change rate. The dependence of the pitting critical temperature is linear in character for all investigated temperature change rates. Values of the critical temperature of pitting corrosion for stationary conditions (E-ES=0) were obtained by using the extrapolation procedure. The critical pitting temperature obtained by extrapolation practically does not depend on the temperature change rate in the investigated range and is equal to 336.9?K (63.9°C).

Notes: The effectiveness of bisquaternary ammonium salt N,N'-Bis(dodecyldimethyl)-3-oxa-1,5- pentanediammonium dichloride used as corrosion inhibitor for carbon steel in 1.0?M HCl was investigated by weight loss and electrochemical techniques. Surfaces were characterised by scanning electron microscopy. The performance of the bisquaternary ammonium salt was also compared with that of urotropine, a commercial corrosion inhibitor for acid media in industry practice. The results showed good inhibiting action of the inhibitor. The inhibition efficiency increases with the inhibitor concentration but is temperature–independent. N,N'-Bis(dodecyldimethyl)-3-oxa-1,5-pentanediammonium dichloride acts mainly as a mixed-type inhibitor. The inhibition of this bisquaternary ammonium compound was assumed to occur via adsorption of the inhibitor molecule on the metal surface without affecting the corrosion mechanisms. The adsorption of the inhibitor on the metal surface in HCl solution was found to obey Frumkin's isotherm.

Notes: The present work was directed to the study of mechanisms of the action of zinc powder as an anticorrosive pigment in coating compositions based on binders that are composed of a two-component epoxy, a single-component polyurethane, and epoxy-ester resins. The results of the study have shown that neutralisation and barrier mechanisms contribute more than the electrochemical mechanism to the effectiveness of the anticorrosion protection. During the investigation, the results obtained in corrosion tests were evaluated by investigating the morphology of coatings by means of electron microscopy procedures.

Notes: The application of hydrogen plasma on corroded steel and excavated iron artefacts has been studied. Transformations of the corrosion layer due to the plasma effect were investigated by means of X-ray diffraction analysis. The reduction of iron oxides to the stable iron oxide, magnetite, was observed for all the samples. In the case of excavated objects, the reduction to magnetite did not occur throughout the whole of the bulk of the oxides, as it does (for example) in the case of steel corroded in the laboratory. Nevertheless, excavated objects, in which a metallic core remained, were stabilised against subsequent corrosion. However, objects that are completely oxidised must be treated carefully, because treatment may result in the formation of a brittle outer layer, and there is a risk of disintegration of such items, if treated using the plasma conditioning and restoration procedure.

Notes: The aluminide and CeO2 and La2O3 containing aluminide coatings on carbon steel have been prepared by a pack cementation process. The influence of CeO2 and La2O3 additions on the oxidation rates of aluminide coatings has been investigated. The performance of coatings was studied by measuring oxidation kinetics, metallography, SEM and X-ray diffraction analysis techniques. The oxidation-resistance of coated carbon steel is discussed on the basis of a decrease in oxidation rates as well as adherence of oxide scales. The oxidation rates of carbon steel and aluminide coatings were markedly reduced in the presence of CeO2 and La2O3 in the temperature range of 700-900°C. The oxidation rates were significantly affected by the morphology of oxide scales. In the case where the structure of oxides scales was not seriously disrupted due to decarburisation, the oxidation rates were significantly reduced.

Notes: The aim of this fieldwork was the study of the effect of 50Hz AC, induced by high-voltage power lines, on the cathodic protection system of a natural gas pipeline. The effectiveness of cathodic protection was checked through in situ long-term monitoring and analysis of pipeline electrical parameters. The results gave an insight into the problems of the cathodic protection system operation, caused by AC interference. An AC and DC potential interdependence was observed, that previously has hardly been reported, and was scrutinized in relation to cathodically protected pipelines. The effects of the AC-interference and low frequency DC potential fluctuations, as well as the potential deviations from the protection potential, are examined. These phenomena are associated with corrosion susceptibility and difficulties in obtaining reliable cathodic protection measurements.

Notes: Several corrosion inhibitors, such as, HEDP, sodium molybdate and zinc ions, were added to an aqueous corrosive media containing different concentrations chloride ions, and the corrosion rates (CRs) of carbon steel were measured at various temperatures. It was shown that, in the presence of more than 1,200?ppm of chloride ions, and temperatures greater than or equal to 42.5°C, the combination of HEDP, molybdate and zinc could not control the corrosion in a cooling water system. Then four different models were designed to represent the CR of carbon steel in presence of various corrosive parameters.

Notes: Sources have been described of corrosively hazardous electric fields and methods of determination of the corrosion hazard to metal structures caused by electrolytic corrosion. Results of potential and impedance investigations in the field of stray currents flowing out of a tram traction and in the presence of a defined electric field of low frequency have been presented. Uncertainties have been indicated relating to the generally accepted interpretation principles of measurement results in the presence of electric fields. The possibility has been indicated of incorporating the impedance spectroscopy technique to potential-voltage investigations, allowing estimation of the real corrosion interaction of stray currents on underground structures.

Notes: This paper gives an overview on the evolution and standards development of the external corrosion protection systems used for flammable and combustible liquids underground storage tanks (USTs) in North America. The paper first describes the different types of corrosion protected USTs for flammable and combustible liquids in North America. It then reviews the advantages and disadvantages of each of the corrosion protection systems used. Finally, it looks forward to some of the technical trends in the North American UST industry and the standard certification process for underground tank external corrosion protection, with updates on the technology and standards in the international UST industry.

Notes: A corrosion study of the intra-uterine device, "TCu 380?A", was made using cyclic voltammetry (CV), scanning electron microscopy (SEM) and optical microscopy (OM). Blood plasma, whole blood and artificial uterine fluid were used as corrosive media in order to establish a comparative scheme of the corrosion behaviour of copper in the device. In summary, the results obtained were not only similar to work reported previously, but also provided complementary data for a better understanding of the corrosion problem.

Notes: A new method of spectral analysis has been proposed for non-stationary harmonic analysis of corrosion processes. The current of a model circuit has been considered which would simulate a first-order electrode reaction proceeding in conditions of a linearly changing electrode potential with a superimposed sinusoid signal. It has been shown that the Fourier transformation approach does not reflect the amplitude changes of harmonic components as a function of constant potential. In addition, it has been shown mathematically that application of Gabor transformation in spectral analysis is a means of obtaining the correct frequency components. The Gabor transform correctly reflects amplitude changes of harmonic components as a function of potential. Digital analysis of current changes by Gabor transformation unequivocally confirmed the usability of this method for harmonic analysis of corrosion processes.

Notes: The beneficial effect of halide ions on the inhibition of corrosion of carbon steel in 20 per cent HCl solution in the presence of some nitrogen-containing compounds, cetyl pyridinium chloride, cetyl pyridinium bromide, and hexamine was investigated using potentiodynamic polarisation measurements. Potentiodynamic polarisation studies revealed that all the tested compounds were of anodic-type inhibitors. All of the compounds were able to reduce the corrosion of carbon steel and their performance was enhanced by the addition of iodide ions. The increase in surface coverage in the presence of the iodide ions indicated that iodide ions enhanced the absorption of inhibitor compounds on the metal surface. Auger electron spectroscopic analysis confirmed the joint absorption of the compounds with KI.

Notes: This paper describes a study on the corrosion behaviour of archaeological bronze in simulated groundwater by means of a simulated occluded cell. The study revealed migration, enrichment and deposition patterns of ions in the environment and the cations produced by anodic dissolution during localised corrosion of bronze. The cycle voltametry technique was utilised for the first time on the study of electrochemical behaviour of the bronze/simulated occluded solution interface. The potential and current peaks of oxidation-reduction at the cathode and anode in the occluded solutions at various time intervals facilitated a study of the corrosion products formation processes and their formation speeds.

Notes: The development of new protective organic coatings is affected by a number of factors, the most important ones at present being those related to environmental acceptability of anticorrosive pigments. An effective solution has been shown to be the application of anticorrosive inorganic pigments based on mixed metal oxides. These pigments consist of spinel and rutile lattice structures. In order to examine the anticorrosive properties, the individual pigments prepared were added to alkyd and styrene-acrylate based test coatings. Both the anticorrosion efficiencies, and the mechanisms of action of the pigments were also evaluated.

Notes: The inhibiting effects of 2,6-ionen and 2,10-ionen type polyvinylbenzyltrimethylammonium chloride, and latex, on low carbon steel in hydrochloric acid solution was investigated by potentiodynamic polarisation measurements and impedance measurement techniques over the temperature range of 20-60°C at different inhibitor concentrations. It was found that the inhibition efficiencies increased with increasing inhibitor concentration. The degree of shift in Ecorr values, together with the change in anodic and cathodic Tafel slopes (ßa, ßc), revealed that the studied inhibitors behaved as anodic inhibitors. Thermodynamic and kinetic parameters for dissolution and adsorption were also calculated.

Notes: The spinel-type pigments of a general formula corresponding to AB2O4 containing as A the Mg2+ or Zn2+ ions and as B the Fe3+ or Al3+ ions or combinations of both the A and B were prepared and investigated with respect to their anticorrosive action as pigments in organic coatings. For the same purposes, comparative pigments, known for their efficiency as the metal-corrosion inhibiting ingredients in similar formulations, were used. Further evaluation was carried out on the properties of condensed phosphates as anticorrosion pigments. The results obtained showed the high anticorrosion action of the spinel-type pigments.

Notes: Stainless steel 316 was coated with CeO2 and Y2O3 modified aluminide and titanium aluminide coatings. The coatings were prepared by the pack cementation method and the high temperature oxidation behaviour of the coatings was investigated in an atmosphere containing a limited supply of air. The performance of the coatings was studied by measuring oxidation kinetics, and by scanning electron microscopic techniques. The oxidation rates of these coatings were reduced in the presence of CeO2 and Y2O3 due to better adherence of their oxide scales.

Notes: This study investigated the corrosion stability of high velocity oxy-fuel (HVOF) spray SUS316L coatings on aluminium substrate as lightweight bipolar plate materials for proton exchange membrane fuel cells (PEMFC). Contact resistance, microhardness and structure of the coatings were characterised using a four-point probe, pneumatic microhardness, XRD and scanning electron microscope techniques. Preliminary electrochemical results indicate that the SUS316L coated plates significantly lowered the corrosion current of the aluminium substrate by more than one order of magnitude. Corrosion stability in relation to the coating thickness is discussed in terms of the structure composition and transpassivity of chromium.

Notes: Electrical industry equipment in the southern parts of Iran have sustained severe damages as a result of corrosive soil containing different kinds of salt, in combination with the corrosive local atmosphere. The present paper is the result of investigations into the behaviour of coatings for various electrical insulators end-fittings. In this research, the performance of Al-Zn alloy coating was compared to conventional galvanized zinc coatings by means of atmospheric corrosion tests. The results demonstrated the higher corrosion resistance of the alloy coatings, compared to that of conventional galvanized coatings. Insulator end-fittings generally are made of steel, which are coated with a hot-dip galvanized coating. The combination of Al and Zn elements in this coating was demonstrated to possess better galvanic protection and lower corrosion rate than did pure zinc.

Notes: The chemical behaviour within the occluded cell of simulated cast iron artefact in 3.5 percent NaCl solution has been investigated by means of a simulated occluded cell. It was observed that the pH value and the amount of Cl- migration in the occluded cell were related to the quantity of passing electric current. Electrochemical techniques were capable of providing information on the behaviour of the cast iron in a simulated occluded cell at various time intervals. The results of potentiodynamic polarisation and impedance measurements indicated that corrosion potentials became more negative and the cast iron was corroded more seriously. SEM micrographs clearly revealed the morphologies of specimens after simulated occluded cell galvanostatic tests for different time intervals at 1?mA/cm2 anodic current density. An auto-catalysing process was responsible for the enrichment of chloride ions in occluded cell which was confirmed by Energy Dispersive Spectroscopy (EDS).

Notes: The effect of benzimidazole-2-tione and benzoxazole-2-tione derivatives on the corrosion of aluminium in 0.1?M HCl has been investigated by a potentiostatic polarisation technique. Inhibition efficiencies were found to follow the order: benzimidazole-2-tione 〉 5-methyl benzimidazole-2-tione 〉 5-chloro benzimidazole-2-tione, while that of benzoxazole-2-tione derivatives were found to follow the order: 5-methyl benzoxazole-2-tione 〉 benzoxazole-2-tione 〉 5-chloro benzoxazole-2-tione 〉 5-nitro benzoxazole-2-tione. The inhibitive action of these heterocyclic compounds was mainly due to adsorption on the metal surfaces, which show parallelism with the calculated total negative charge of each of the molecules. Thermodynamic parameters, such as values of free energies of adsorption ?Gads and values of equilibrium constants Kads, were determined. Activation energies Ea, activation enthalpies ?H* and activation entropies ?S* were determined from the corrosion currents measured at different temperatures.

Notes: The oxidation behaviour of a wrought Ni-Mo-Cr alloy was studied under thermal cyclic conditions in air at 800°C for exposure periods of up to 1,000?h. The morphologies, microstructures and compositions of the oxide scales were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction. Oxidation kinetics were determined by weight gain measurements. Results show that steady-state oxidation was achieved within 1?h of exposure while partial scale spalling was observed after 400?h. The alloy grain boundaries intersecting the alloy surface showed preferential oxidation. They became depleted in Ni and enriched in Mo and Cr during transient oxidation. The scale initially formed at the surface was NiO which grew outwardly and laterally to cover the entire alloy. Upon continued oxidation, the scale developed into an outer NiO layer and an inner Cr2O3 layer while the presence of NiMoO4 was also observed within the scale.

Notes: Three thiosemicarbazone derivatives were synthesised: p-chlorobenzylideneamino thiosemicarbazone, p-itrobenzylideneamino thiosemicarbazone and p-N,N?'-dimethylminobenzylideneamino thiosemicarbazone. The structures of these compounds were characterised by elemental analysis, IR, 1H NMR and UV spectral measurements. The antifouling properties of the compounds were evaluated through the incorporation of each compound in a marine coating system and testing the system in Alexandria Eastern Harbour water. The results are discussed in the light of the leaching rate of the compounds from their paint films, and their interaction with paint matrix.

Notes: Purpose - The objective of the present work was to study the kinetics of copper cementation on Fe metal in an acetone-water medium and in a dioxane-water medium. Design/methodology/approach - The impact of solvent concentration on cementation rate was determined by measuring the rate of copper cementation from CuSO4 onto an iron plate in the absence and in the presence of acetone and dioxane solvents.The thermodynamic parameters ?H#, ?S# and ?G# of the cementation of CuSO4-organic solvents were calculated. Linear plots of ?H# versus ?S# were obtained. Findings - It was demonstrated that the rate of cementation decreased with increasing concentration of solvents and increasing temperature. The isokinetic temperature data indicate that the cementation reaction is controlled by the entropy of the system. Originality/value - The findings have important implications for the reclamation of toxic and valuable metals from industrial waste streams.

Notes: Purpose - Work reported in the present paper investigated the inhibiting properties of a number of N-heterocyclic amines in 0.1?mol/l HClO4. An attempt also was made to correlate some molecular parameters of these compounds with their corrosion inhibitor efficiency. Design/methodology/approach - The test series included piperidine (pip), 2-methylpiperidine (2mp), 3-methylpiperidine (3mp), cis-2,6-dimethylpiperidine (26dp), 3,5-dimethylpiperidine (35dp), 3-hydroxy piperidine (3hp), 4-hydroxypiperidine (4hp), 4-aminopiperidine (4ap), piperazine (pz), 2-methylpiperazine (2mpz) and cis-2,6-dimethylpiperazine (26dpz). The inhibiting effect was investigated in 0.1&?mol/L HClO4 by potentiodynamic polarization (DC) and electrochemical impedance spectroscopy (EIS). Findings - The results show that these compounds suppressed both cathodic and anodic processes of iron corrosion in 0.1?mol/l HClO4 by adsorption on the surface, which followed a Langmuir adsorption isotherm. Experimental observations indicated that basic piperidine and piperazine were better corrosion inhibitors than were their derivatives. The inhibition properties of N-heterocyclic amines were found to be related to the charge on the nitrogen atom and the sum of the net charge of the all six atoms from the cyclic ring. Originality/value - This paper provides useful information relative to corrosion inhibition efficiency of the group of N-heterocyclic amines. It is concerned with a theoretical explanation between electronic and structural characteristics of these compounds and their inhibitor efficiency.

Notes: Purpose - The evaluation of Schiff bases derived from o-, m- and p-aminophenols and salicylaldehyde as corrosion inhibitors of zinc in sulfuric acid and to study their action mechanism. Design/methodology/approach - The effect of various parameters on the behaviour of these inhibitors has been studied using the weight loss and polarization measurements. Findings - In general, the ortho isomer was highly effective as a corrosion inhibitor because it formed a chelate with a six-membered ring and moreover the ortho isomer possessed pronounced electromeric effect. These inhibitors obey the Langmuir adsorption isotherm. The almost constant performance with temperature in the case of ortho and para isomers in 0.5?M sulfuric acid suggested strong adsorption bonds. The thermodynamic parameters suggested that this strong interaction of the inhibitor molecules with the metal surface resulted in spontaneous adsorption. It may be concluded that a good inhibitor is characterised by a relatively greater decrease in free energy of adsorption, lower entropy of adsorption and higher heat of adsorption. Polarization data indicated that all these isomers were predominantly cathodic inhibitors. The conjoint effect of external cathodic current and these inhibitors was either synergistic or additive. Research limitations/implications - Even more powerful Schiff bases need to be synthesised and evaluated as corrosion inhibitors with a number of metals and alloys in diverse media, which may be effective at low concentrations. Originality/value - Very few inhibitors exhibit such excellent inhibitive effect on zinc in aggressive corrosive media. Rarely do we find such detailed studies.

Notes: Purpose - To demonstrate corrosion inhibition capabilities of new cyclic nitrones, containing hydrophobic substituents. Design/methodology/approach - A number of new cyclic nitrones were synthesized. Corrosion inhibition efficiencies of these organic inhibitors were determined by gravimetric and electrochemical methods, using carbon steel as the substrate metal and 1?M HCl at 60°C as the corrosive environment. Concentration of inhibitor was varied between 50 and 400?ppm. Findings - All compounds exhibited excellent corrosion efficiencies that ranged between 90.0 and 98.3 percent in 1?M HCl at 60°C. Tafel tests corroborated these results. Research limitations/implications - The inhibitors were tested in acidic medium. It is unknown how these inhibitors will function in the presence of other ions that are typically present in natural corrosive environment. Originality/value - All organic compounds presented in this work are new and this is the first time their corrosion inhibition characteristics have been evaluated.

Notes: Purpose - To study the effects of isomers of organic compounds such as phenylenediamine, toluidine and nitroaniline as inhibitors for the corrosion of carbon steel in sulfuric acid. Design/methodology/approach - Standard methods have been adopted in this study such as weight loss, polarization tests, impedance measurements and hydrogen permeation studies to find out the corrosion behavior of carbon steel in sulfuric acid with and without inhibitors. Findings - All the selected isomers inhibited the corrosion. The best performance was found in ortho-phenylenediamine when compared with other inhibitors under study. Originality/value - It clearly shows the effect of isomers of phenylenediamine, toluidine and nitroaniline. The method of study may be applicable to find out the performance of other isomers of organic compounds. As these isomers behave as good inhibitors in sulfuric acid, these may be tried as inhibitors in other acids. Hence, this study is useful to academics and researchers in the field of corrosion science and engineering.

Notes: Purpose - To evaluate the corrosion performance and nano-mechanical behaviour of a brass substrate covered by different thick SiO2 layers deposited by means of plasma enhanced chemical vapour deposition (PECVD) technique. Design/methodology/approach - The comparison between laboratory and "industrial" objects revealed a very good corrosion behaviour and good mechanical performance of both of them: in particular it was possible to modulate the surface treatment to solve various problems from the industrial point of view. Findings - It was possible to reduce the Cu migration into the SiO2 coating during the PECVD deposition at a negligible level and to control it by the deposition; further, the nano-indentation tests revealed the great utility of the coating annealing in obtaining a significant improvement of the mechanical properties of the coated objects. Research limitations/implications - Even if some industrial problems were solved (minimization of the presence of the coating defects and transparency of the coatings), some on the layer hardness (anti-wear behaviour of the industrial objects) has to be better investigated and possibly solved. Practical implications - The work reports a deposition process that is carried out industrially over a two year period. Originality/value - This research reports a PECVD process realized on industrial objects: the originality is in the reached corrosion and mechanical performances that made it possible to realize a satisfactory industrial deposition.

Notes: Purpose - To investigate the inhibitive effect of Congo red dye (CR) for aluminium corrosion in strong alkaline solutions and evaluate the synergistic effect of halide ions on the inhibition efficiency. Design/methodology/approach - Corrosion rates of aluminium test coupons were determined by gravimetric technique at 30 and 60°C. Inhibition efficiencies of the additives (0.01-5.0?mM CR and 5.0?mM CR+0.5?mM halides) were evaluated by comparing corrosion rates of the test coupons in 2?M KOH solution in the absence and presence of the additives. Findings - CR inhibited aluminium corrosion in 2?M KOH by physical adsorption of the dye molecules on the corroding metal surface. Maximum efficiency at 30 and 60°C was 31.72 and 19.32 per cent, respectively. Dye adsorption was enhanced in the presence of halides in the order KCl?〈?KBr?〈?KI, with KI increasing efficiency up to 48.63 and 41.70 per cent at 30 and 60°C, respectively. Research limitations/implications - Further studies to involve variation of dye and halide concentrations for CR+halide systems to determine the best combination for optimum inhibition synergism. Originality/value - This paper forms part of an extensive database on the inhibition characteristics of organic dyes for corrosion of different metals in various aggressive environments. This is to serve as a guide to possible applications in metal-surface anodizing and as additives in surface coatings for service in different environments.

Notes: This paper presents an investigation for analyzing the efficiency of axial piston pumps in a variety conditions using a proposed neural network. Since slippers affect the performance of the system considerably, the effects of surface roughness on lubrication have been studied in slippers with varying hydrostatic bearing areas and surface roughness. The neural network structure is very suitable for this kind of system. The network is capable of predicting the leakage oil quantity of the experimental system. The network has parallel structure and fast learning capacity. It is also easy to see from the experimental results that the leakage oil quantity was caused by surface roughness, orifice diameter and the size of hydrostatic bearing area, loading pressure and the number of rotations. It can be outlined from the results for both approaches, neural network could be modeled slipper bearing systems in real time applications.

Notes: Surface roughness, normally defined by the Ra and Rt/Rmax parameters, is an important topic in the manufacturing engineering, for controlling produced components. This paper presents a study of the influence of cutting parameters on surface roughness in turning of glass-fibre-reinforced plastics (GFRPs). A plan of experiments was performed on controlled machining with cutting parameters prefixed in workpiece. A statistical technique, using orthogonal arrays and analysis of variance, has been employed to investigate the influence of cutting parameters on surface roughness in turning GFRPs tubes using polycrystalline diamond cutting tools. The objective was to obtain the contribution percentages of the cutting parameters (cutting velocity and feed rate) on the surface roughness in GFRPs workpiece.

Notes: Purpose - The present paper proposes a theoretical analysis of the stability characteristics of a Jeffcott rotor-hybrid bearing system. It is intended that on the basis of the numerical results drawn from this study, appropriate recess depth, land size, orifice location and speed parameter for stable operation can be determined for use in the bearing design process. Design/methodology/approach - A Jeffcott rotor supported by hybrid oil film bearings with dual-row recesses and orifice- compensated restrictors is studied. In order to facilitate the calculation of film dynamics, using the perturbation method, the Reynolds equation was linearized and subsequently solved using finite difference techniques, whilst the stability maps were determined by the Routh-Hurwitz method. Findings - The data reported here suggest that the stability characteristics of the Jeffcott rotor-bearing system could be improved by the use of shallow, dual-recessed hybrid bearings with orifice compensation. In addition to greater eccentricity ratios, smaller land-width ratios and greater shaft stiffness may also provide shallow-recessed bearings with better stability. In all cases, the stability provided by upstream orifice-sited bearings is better than that provided by center orifice-sited bearings, whilst high-speed parameters may also provide a greater stability threshold. Originality/value - This study proposes an extensive database as a critical requirement in the design of hybrid bearings, in order to ensure that a rotor bearing system is operating stably.

Notes: The tribological properties such as surface hardness, friction and wear have been studied for AISI 316L stainless steel substrates which were co-ion implanted with zirconium and oxygen ions. It is found that the wear resistance for AISI 316L stainless steel substrates implanted with zirconium and oxygen ions increased quite a lot. It is concluded that the increase in surface microhardness and the decrease in friction coefficient of AISI 316L stainless steel substrates play an important role in improving the wear resistance, and the relationship between relative wear volume and microhardness is correlated for zirconium and oxygen co-ion implantation.

Notes: The objective of this paper is to construct a continuous model for the viscoelastic contact of a nominal flat punch and a smooth surface of a rigid half-space. The considered model aims at studying the normal approach as a function of the applied load. The proposed model assumes the punch surface material to behave according to Kelvin-Voigt viscoelastic material. The punch surface, which is known to be fractal in nature, is modelled in this work using a deterministic Cantor structure. An asymptotic power law, deduced using iterative relations, is used to express the punch surface approach as a function of the remote force when the approach of the punch surface and the half space is in the order of the size of the surface roughness. The results obtained using this model, which admits closed form solution, are displayed graphically for selected values of the system parameters; the fractal surface roughness and various material properties. The obtained results showed good agreement with published experimental results.

Notes: Purpose - The purpose of the present study is to provide the dynamic characteristics of long journal bearings lubricated with couple stress fluids. Design/methodology/approach - Based upon the micro-continuum theory generated by Stokes, the dynamic Reynolds-type equation governing the film pressure is derived to account for the couple stress effects resulting from the non-Newtonian behavior of complex fluids. By applying the linear stability theory to the non-linear equations of motion the journal rotor, the equilibrium positions and dynamic characteristics of the system are evaluated. Findings - As compared to the classical Newtonian model, the effects of couple stresses signify enhanced stiffness and damping coefficients (including KXX, KXY?, BXX and BXY) at moderate values of the steady eccentricity ratio. Totally, as the rotor center operates at an eccentricity ratio about ?s=0.71, long bearings lubricated with couple stress fluids under small disturbance results in a higher stability threshold speed than that of the Newtonian-lubricant case. Originality/value - These findings provide engineers useful information in designing journal-bearing systems.

Notes: Purpose - The aim of the research is to investigate the ceramic brake lining on the brake performance.Design/methodology/approach - The brake lining which has new formulation has been produced by using various additive materials. Various techniques have been used in the production of brake lining. These ceramic linings were subjected to friction and wear tests under different loads, and changes in the hardness and microstructures were examined.Findings - As a result of this study, the following findings are reported. A direct proportional was not found between hardness and wear resistance due to the complexity of composite structure. Kevlar fibers were homogeneously distributed in the matrix and therefore, very few microvoids were observed in the structure. Similarly, stone wool was well spread out the braking pad and hence decreased the microvoids' occurrence. Heat treatment supplied more homogeneous structure and hence, microstructural variations were minimised during the brake action. On the other hand, heat treatment decreased the hardness of glass fiber reinforced specimens and increased the density. Each specimen was affected from the environmental conditions. However, water affected all specimens more than the other environmental conditions, such as salty water, oil and braking liquid. With the increasing of temperature, the ingredients in the braking pad were affected other due to better diffusion. On the other hand, hardness of specimens increases and density decreases due to heat treatment and also specific wear ratio changes.Research limitations/implications - Limitations in the present research are as follows: two different pressures and eight different temperatures were used and brake linings were subjected to wear test, hardness tests, microstructures were examined.Practical implications - For future work, instead of buying expensive brake lining, new and cheaper ceramic linings are produced. By this process, economic benefit can be gained and also environmental protection can be succeeded in producing such asbestos free brake linings.Originality/value - This paper fulfills an identified information and offers practical help to the industrial firms working with brake lining and also to the academicians working on wear of materials.

Notes: Purpose - The aim of the research is to investigate the influence of ceramic coating on the wear performance of machine parts. Design/methodology/approach - Ductile cast iron parts were coated using ceramics. Three ceramics were used for this purpose. These coated parts were subjected to wear tests under a stable load. A pin-on-disc wear test apparatus was used. Findings - As a result of this study, the following findings are reported: According to ASTM G 99-90 pin-on-disc experiments, Cr2O3 was found to be best coating material with low wearing rate. Within row, Al2O3 and ZrO2 can be given. According to the previous work, motor parts for example piston ring, cylinder liner and engine valve can be coated with ceramic. In this study, it is observed that the figure of merit is increased in this study. Only wearing data is given in this research. The other results are also supporter of the results taken from the wearing experiments. As a result, due to the decrease in heat loss and coaling stability of part can provide good results. With these, by coating there is a decrease in oil reduction. Research limitations/implications - Coatings were limited with three ceramics, a stable load was used, and coated parts were subjected to wear test. Practical implications - For future work, instead of using other coating materials, Cr2O3 is used for the best coating material with low wearing rate. By this process, working life of the machine parts can be extended and a number of economical advantages may also be obtained. Originality/value - This paper fulfills identified information needs and offers practical help to the industrial firms working with ceramic coating and also to the academicians working on wear of materials.

Notes: Purpose - Improved fuel economy, lower emission and longer durability are the major developing trends of engine oils. Aims to describe further research on the friction coefficient of engine oils. Design/methodology/approach - The lubricating durability D was defined based on definition of three characteristic points Pd, PS, Pi and three key time lengths Td, Ts, Ti. Two kinds of engine oils, respectively, belonging to GF-2 and GF-3 categories, were selected as samples to compare their lubricating durability. Findings - Test results indicate the GF-3 oil has much better lubricating durability than GF-2 oil. With investigation of the topography and chemical composition changes of wear tracks along with the tribotests' time extending, the meanings of three characteristic points were discussed. Analysis indicates much better tribofilm, formed by the synergistic effect of Ca-containing detergent with MoDTC/ZDTP in GF-3 oil, is the major factor resulting in GF-3 oil's longer lubricating durability. Originality/value - Provides further research on lubricating durability, which is important for engine oil change and maintenance, as well as decreased cost and pollution to the environment, and improved energy conservation.

Notes: Purpose - PEEK is an abbreviation for polyetheretherketone, a high performance engineering semicrystalline thermoplastic. This material can operate at higher temperatures and has excellent friction and wear properties, which are optimised in the specially formulated tribological grade PEEK-CF30. The purpose of this work was to develop a thermo-mechanical model to predict the tribological behaviour of the composite PEEK-CF30/steel pair, in dry sliding, related to friction and wear with the pv factor, the temperature and the sliding distance, using multiple regression analysis (MRA). Design/methodology/approach - This paper presents a new thermo-mechanical model to predict the tribological behaviour of the composite PEEK-CF30/steel pair, in dry sliding, using MRA. A plan of experiments was performed on a pin-on-disc machine PLINT TE67HT®. Findings - The objective was to establish a thermo-mechanical model to predict the PEEK-CF30 behaviour related to friction and wear with the pv factor (product of apparent pressure of contact and sliding velocity), the temperature and the sliding distance. This model was obtained by multiple linear regression. Finally, confirmation tests were performed to make a comparison between the obtained results from the mentioned model and the experimental results. Originality/value - The novel element of this paper is the application of design experiments and MRA in tribological model behaviour in an advanced material - PEEK-CF 30.

Notes: During the last ten years, a gradual conversion from mineral oil based hydraulic fluids to environmentally adapted lubricants (EALs), has taken place in the forest industry in Sweden. The current market share of the EALs is ca. 80 percent of the mobile hydraulic fluids utilised. The original driving force of this change can be traced to end-user demands, especially paper and pulp consumers in Germany. The Swedish standard SS 15 54 34 was in 1997 supplemented with environmental criteria derived from the "Ren Smörja" ("Clean Lubrication") environmental project in the city of Göteborg. The reliable third-party validation offered by SP (Swedish National Testing and Research Institute), the present stewards of the "Clean Lubrication" list, has proven to be another important factor. By comparison to the German Blue Angel Eco-labelling scheme, the Swedish SP-list approval is somewhat easier to attain, and has provided a flexible base for the development of new products.

Notes: This paper reviews the performance features of a new generation of industrial gear oils, developed for both mineral and synthetic base oils. These new products were designed to provide the highest levels of protection against the relatively new wear mechanism called micropitting. However, great stress was placed on providing these new products with balanced performance capabilities, so that they will perform with high reliability in the wide variety of conditions to which modern industrial gear oils are exposed. Performance areas such as filterability, foam control, corrosion protection, water separation, oxidation control and bearing protection were of particular concern. This paper compares the overall performance of these new technologies with conventional commercial products and it describes the extensive rig and field-testing used to confirm their performance. It also reviews the phenomenon of gear micropitting and optimum methods for its assessment.

Notes: Tribology problems occurring in high performance tape and disk systems are discussed. The head/medium interface is described for the case of lightly loaded contacts between a magnetic tape and a read/write head, and the parameters determining the design and the tribological performance of the head/flexible medium interface are discussed. In addition, the head/disk interface in the case of very small spacing is analyzed and the tribology problems encountered in the case of very small head/disk spacing are summarized. Finally, an overview of future tribology trends in magnetic recording technology is given.

Notes: One of the most promising synergistic compositions for use in high-temperature lubricants comprises aromatic amine and an oil-soluble alkali metal compound although action mechanism of this synergism is still questionable. The greatest efficiency of this additive pair is demonstrated for PEE based compositions using thin-layer oxidation test at 250°C. Addition of potassium-containing additive to aromatic amine antioxidant results in decreasing of formation of strongly-oxidized substances. Determination of electrophysical parameters (dielectric constant and specific conductivity) for tested samples indicates formation of reversed micelles at the potassium content of about 0.6·10-2 mol/l, and the latter corresponds to the potassium content that provides the highest antioxidant efficiency. A novel method of inhibiting oxidation is proposed: micellar inhibition that suggests novel possibilities for protection of lubricants against oxidative degradation.

Notes: The paper discusses the setup of a light duty axle efficiency test in evaluating gear lubricants for their fuel economy performance. Data collected with an internal reference oil highlight the repeatability of the test in different axles. Comparisons between single grade SAE 90 to multigrade gear lubricants were made under a variety of pinion torques and speeds to simulate highway and city driving conditions. A discussion of lubricant rheology and its importance to maintaining film strength for adequate bearing and gear lubrication for optimum torque efficiency and axle temperature is provided.

Notes: This paper presents a tribological analysis of a grease lubricated contact with a consideration of the grease structure (density distribution).

Notes: In this paper a new method for the hydrodynamic analysis of a sliding cylinder in a lubricated parallel track is presented. The method is an extension of Booker's "Mobility Method" (developed for cylindrical journal bearings) for the case of a non-rotating sliding cylinder in a parallel track. In this application, the clearance between the track and the cylinder, the viscosity of the lubricant, the radius and length of the pin, the sliding velocity and the applied transverse load determine the hydrodynamic behavior of the slider cylinder. An axial positive displacement vane device is used to illustrate the applicability of the hydrodynamic mobility approach for a lubrication analysis. A rotor and a stationary cylindrical cam with cycloidal tracks drive the axicycloidal motion of vanes. A case analysis is presented for a device running at constant speed, in which the inertia forces, friction forces and direct vane loads are taken into account to determine the hydrodynamic behavior of the sliding pins. The following results are produced: pin eccentricity paths, minimum lubricant film thickness history, peak film pressure history and pressure distributions on the cylindrical at any point of the motion. Results show small departures from the purely cycloidal lift-dwell-return-dwell motion of the vanes due to the hydrodynamic performance of the pins.

Notes: The process of finding the ultimate grease is described in this report using an example from railway applications. This example includes steps such as a requirement list, field tests, laboratory tests and an evaluation method. The example deals with the problems discovered in a field test performed to determine the best grease for tapered roller bearings in railway wagon wheels and to increase the knowledge of grease lubrication. Seven different fully formulated commercial greases were examined in the wheel bearings of one ore wagon, used for transporting ore commercially by railway from the Kiruna Mine in northern Sweden to Narvik in northern Norway for shipping to foreign markets. The steps performed in this study are recommended in all problems associated with finding the optimal grease for different types of applications.

Notes: During the first decades of the next millennium, automobile manufacturers will strive to achieve, in the USA, another twofold increase in energy efficiency and tenfold reduction in emission levels. On the way to achieving these goals, automobile manufacturers will be improving efficiency and emissions of internal combustion engines, while minimizing customer servicing requirements, as well as introducing new unconventional engine technologies and gradually changing energy sourcing from oil to gas, and possibly to hydrogen. Numerous supporting technologies, such as electronics, computers, sensors, fuels, catalysts, lubricants, etc., will be involved in contributing to engine system improvements. This paper describes expected improvements and changes in lubricant technology and points out the need for development of "breakthrough" technologies which could satisfy the near-term requirements and eventually in the long term, in combination with novel surface technologies and engine design changes, lead to fill-for-life engine lubrication.

Notes: Antiwear mechanism of action of some chemical elements added to lubricant is studied. These elements are transferred from the lubricant into the surface layers of the sliding pair during friction. The mechanism is based on the influence of these elements on the stacking fault energy (SFE) of the materials in the friction pair and leads to changes in the fragmented structure formed in the metals under plastic deformation. Work hardening of the metal surface layers and their predisposition to wear are changed accordingly. Copper and Armco iron, as typical FCC and BCC metals, were chosen for the friction pair materials. Si, Ni, Zn, Co and Ti were used as the additive components to the lubricant. It was found that the addition of different elements to the lubricant leads to alloying by these elements of the surface layers of the metal during the process of friction. It was found that alloying by elements which decreases the SFE of the metal, the average size of surface layer fragments formed during friction increases and the wear rate decreases. The possibility of controlling the wear resistance of metals during friction through the use of appropriate additives is discussed.

Notes: This paper looks at the development of prelubes, new coating fluids which can eliminate application of further specialist deep drawing compounds at the press shop. The work carried out by the German Motor Industry, VDA, to establish a specification for prelubes is highlighted, and the full sequence of tests and stages built into this new specification is outlined.

Notes: Lubricants are very complex mixtures of components. To predict their behaviour over a long time it is necessary to make a lot of machinery element tests. This paper tries to give an insight into how lubricants can be estimated in their structure by IR-microscopy and how this procedure could lead to a short prediction of their long-time behaviour in time- and cost-expansive machinery element testing.

Notes: A study of piston ring-cylinder tribological behaviour under mixed lubrication mode is usually based upon data regarding surface contact magnitudes, fluid film characteristics and resultant mixed friction forces. The present paper introduces a Fisher-Pearson statistical model to describe elastic deformation of piston rings and liners' asperities in order to derive more realistic functions that represent the aforementioned functional quantities considering real surfaces of used and worn liners. The hypothesis that the microtopography follows Gaussian law overestimates critical contact magnitudes such as: minimum film thickness-surface separation distance, deformed asperities supported load, number of contacts and contact area. Increased time of use and wear of liners decreases transverse geometrical anisotropy. Correction contact integral functions in cases of used liners' surfaces may be calculated through surface profile measurements. Theoretical and experimental results are in good agreement for the configuration considered.

Notes: Efforts have been made to study the optimum film profile for a longitudinally rough slider bearing. The roughness of the bearing surface is modelled by stochastic random variable with non-zero mean, variance and skewness. The governing differential equation for lubricant pressure is the Reynolds equation which is stochastically averaged with respect to the random roughness parameter. The method of infinitesimal is used to determine the optimum lubricant film profile. Results for the step location, step height ratio and the bearing performance characteristics, such as load carrying capacity of the bearing, centre of pressure, frictional force and coefficient of friction for different values of a, s and e, are numerically computed and tabulated. It is observed that the parameters a, s and e characterizing the surface roughness of the bearing affect the bearing performance characteristics significantly.

Notes: Increasingly stringent European market requirements for improved heavy duty diesel engine performance, such as fuel economy and durability, continue to highlight the need for higher performance engine lubricants. To meet this need, new additive technology is being used in combination with higher quality base-stocks and has resulted in a growing trend towards the use of oils of lower viscosities than those used in the past. Such a trend has led to some concern over the ability of low viscous oils to maintain adequate engine wear protection, not only during extended service operations but also under the more severe conditions of low temperature engine start-up. This paper describes the results of a recent study to evaluate the effect of base oil composition and viscosity grade on the low temperature performance of a modern Euro II diesel engine with respect to wear, using the technique of Thin Layer Activation. Engine test results showed that the use of full synthetic SAE 5W40 grade oils based on Polyalphaolefin provided enhanced low temperature cylinder liner wear protection.

Notes: Commercial oil fortifier was added to fully-formulated crankcase oils, and their performance, in terms of friction, wear and, most importantly, the role of the additive protective layer on the sliding surfaces, was investigated. Tests were performed on a pin-on-disc machine using steel and steel sliding partners under boundary lubrication conditions. Tests were carried out at a constant load and velocity at different temperatures with different lubricants and the results were achieved using analytical methods such as light microscopy, electron microscopy and X-ray diffraction. Related to the experimental work, lubricants and the lubricants containing oil fortifier presented satisfactory protective additive layers which were identified on the wear track at high and low temperatures.

Notes: In electrical motors electrical energy is transformed into mechanical energy or vice versa. Electrical energy has to be transferred from a stationary component into a moving one, which is done by a copper commutator in sliding contact with carbon brushes. Wear occurs at surfaces of both components during dry sliding. To reduce friction and wear rate, solid lubricants are added to the carbon brush compositions. It was observed that, during sliding, a solid lubricant film is formed on the surface of the copper commutator. This transfer film has a limited life. After failure of the layer a new film is formed from the reservoir of the carbon brushes. Various solid lubricants in carbon brushes were tested. It was found that certain solids form very thin layers with good adhesion on commutator surfaces, which improves tribological performance of both moving components. In particular, wear rate, friction and noise are reduced significantly. This resulted in much longer service life of electrical motors for automotive applications.

Notes: Dry sliding of different components over each other results in changes of interfaces. During the running-in procedure a surface accommodation takes place. There is transfer of material from the softer to the harder component. At the surface of a composite a friction layer is formed, which has a different chemistry than the matrix. Type of friction layer and transfer layer govern the tribological performance of a dry sliding system. In order to arrive at desired frictional properties various additives are added to composites. Change of tribological performance by use of solid lubricants in dry bearings, carbon brushes and brake linings is discussed.

Notes: Inconel 617 alloy is widely used in industry due to its superior high temperature properties. After long periods of operation, the alloy microstructure changes. One of the methods to regain the alloy microstructure is heat treatment at elevated temperatures. In the present study, electrochemical and mechanical responses of Inconel 617 alloy over 30,000 hours of operation as a transition-piece in agas turbine engine are examined. The heat treatment process at two different temperature levels is applied when refurbishing the alloy microstructure. The electrochemical tests are conducted to investigate the corrosion response of the alloy before and after the heat treatment process. Fatigue and tensile tests are carried out for the workpieces subjected to the electrochemical tests. SEM is introduced to examine the fractured surfaces.

Notes: Two 10W30 mineral-base phosphorus containing (commercial) and phosphorus-free (P-Free) crankcase oils were tested in the engine dynamometer for the poisoning effects on a catalytic converter and emission-engine's performance. The emission results of the two oils were compared with and without a catalytic converter, including the light-off temperature of the catalyst. Surface characterisation was used to determine accumulated catalyst poisoning from the oil additives. The performance analysis shows that the catalytic converter lowers the torque and power for the commercial and P-Free oils, whereas the specific fuel consumption increases for both oils in the presence of the catalytic converter. In both cases of the presence and the absence of catalytic converter the torque, power and specific fuel consumption remain the same for phosphorus containing and P-Free oils. The presence of the catalytic converter shows lower HC and CO and higher CO2 emissions for both P-Free and commercial oils. Surface characterisation using x-ray microanalysis techniques of Scanning Electron Microscopy and indicated residual amounts of poisons, predominantly P, Ca, S and Zn deposited on the catalyst.

Notes: Quantifiable data in a report by the Environment Agency of England and Wales entitled Water Pollution Incidents in England and Wales 1997 identifies over 3,723 substantiated pollution incidents across England and Wales in 1997. The construction industry was the most frequent polluter responsible for 22 percent of all substantiated water-related pollution incidents in the "Industry" sector. Also 28 percent of all substantiated pollution incidents across England and Wales are directly attributable to mineral-based fuels and oils, many of which are used extensively within the construction industry. Seeks to locate the possible causes and effects for some of that oil-based pollution, discusses the issues and identifies a client-motivated solution to reduce and mitigate the undesirable impacts upon the environment. One particularly aggressive pollutant - hydraulic oil - remains annually, unaccounted for. Hydraulic oil is used in most tracked earthmoving machinery; machinery most closely associated with construction work carried out near to watercourses. Biodegradable hydraulic oil is much more considerate to the environment, but is more expensive and not usually installed in new plant and machinery. Argues that on a life cycle basis the use of biodegradable oil is viable and feasible and external factors make its usage desirable.

Notes: In this paper, computer-aided design optimization approach for hydrostatic bearings is presented. The optimization problem is formulated in multicriteria strategy. The power loss and the temperature rise of oil are considered as performance measures for optimal hydrostatic bearing design. Optimization results indicate the effectiveness of the proposed combined approach which has advantages over the single criteria optimization. Sample results are presented to verify the proposed approach.

Notes: Coating is a process applied to surface of materials to have thermal insulation, hot corrosion, erosion and oxidation resistance. Due to their combination of high hardness and chemical stability, thin titanium nitride and Tinalox PVD coatings have been successfully established in surface engineering. In the present study, wear and friction characteristics of TiN and Tinalox PVD coated ASME 316L stainless steel were investigated and compared with the substrate. To do this, friction and wear tests were done using Tribotester, S/N: 07-128 CSEM machine. Also, hardness variation was determined by means of CSEM Nano-Hardness Tester S/N: 4-113. It was seen that hardness was increased in TiN and Tinalox coated substrates, while friction coefficient and wear rate decreased.

Notes: The squeeze-film characteristics between two parallel rectangular plates with an electrically conducting fluid in the presence of a transverse magnetic field are analyzed. The squeeze-film Reynolds equation applicable to the curved surfaces is derived using the continuity equation and the magneto-hydrodynamic (MHD) motion equations. A closed-form solution is obtained for the squeeze-film pressure of parallel rectangular plates, and applied to predict the squeeze-film behavior. According to the results, the presence of magnetic fields signifies an enhancement in the squeeze-film pressure. On the whole, the magnetic-field effect characterized by the Hartmann number provides an increase in value of the load-carrying capacity and the response time as compared to the classical non-conducting lubricant case, especially for larger values of the aspect ratio or smaller values of film height.