ISSN:
1573-4889
Keywords:
oxidation
;
reactive-element effect
;
reactive-element oxysulfide
;
reactive-element oxide
;
reactive-element orthochromite
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Nickel-base alloys of nominal composition Ni-25 Wt.% Cr-(0-0.6 Wt.%) RE (RE=Y, La, and Ce) were prepared by conventional arc-melting Ni, Cr, and Y metal. The microstructure of the alloys was characterized by using electron diffraction and X-ray energy dispersive spectroscopy (XEDS) to determine the structure, morphology, and distribution of second-phase particles. Selected alloys were oxidized at 900°C and 1000°C in 1-atm air, and the resultant oxide scales were characterized using the same analytical techniques. The experimentally determined electron-diffraction data were compared with a JCPDF-EDD database, and several compounds were matched. The observed phases were RE oxysulfide, cerium orthochromite-CeCrO3, yttria-Y2O3, yttrium orthochromite-YCrO3, and Ni5Y. The significance of these observations is discussed with respect to the current level of knowledge on the role of sulfur in the reactive-element effect. The ability of the reactive elements to getter sulfur is examined with respect to the thermodynamic stability of the oxysulfide species.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01046892
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