ISSN:
1573-4889
Keywords:
sulfidation corrosion
;
whisker morphology
;
kinetic transitions
;
diffusion
;
preformed-oxide layer
;
texture
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Sulfidation corrosion of 4130 steel in CH3SH was studied in the temperature range 250–550°C. The rate of sulfidation attack was found to be a function of temperature and sulfur activity. Investigations of the corrosion process led to the proposal of two mechanisms of sulfidation, dependent on temperature. Cation diffusion through the iron sulfide corrosion product is the rate-determining step at higher temperatures (〉370°C), while a surface reaction was identified as the rate-limiting step at lower temperatures. The corrosion scale has preferred orientation as determined by X-ray diffraction and morphological observations. The lower-temperature corrosion product is made up of columnar grains of pyrrhotite crystals with the c-axis aligned nearly perpendicular to the steel substrate. At high temperatures, a whisker morphology developed with the whiskers having variable texture with respect to the steel substrate. A preformed-surface-oxide layer on 4130 steel does not appear to significantly reduce sulfidation corrosion.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01113369
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