Journal ArticleDOI
The scaling of a Fe-20Cr alloy in H2-H2O-H2S mixtures
W. F. Chu,A. Rahmel +1 more
TLDR
In this article, the scaling of an Fe-20Cr alloy was studied in H2-H2O-H 2S mixtures between 973 and 1223 K. The reaction followed a mixed rate law between linear and parabolic, indicating that the reaction rate at the scale-gas interface was comparable with the diffusion rate in the scale.Abstract:
The scaling of an Fe-20Cr alloy has been studied in H2-H2O-H2S mixtures between 973 and 1223 K. According to a simplified phase diagram, Cr2O3 and FeS should be the thermodynamically stable compounds in the gas mixtures chosen. The reaction followed a mixed rate law between linear and parabolic, indicating that the reaction rate at the scale-gas interface was comparable with the diffusion rate in the scale. At a constant H2/H2S ratio the scaling rate initially decreased slightly with increasing water-vapor pressure. A further increase of the water-vapor pressure resulted in localized sulfide formation, while the other parts of the surface were covered with a Cr2O3 film. Only Cr2O3 formed above a critical water-vapor content. Three zones could be distinguished when a sulfide scale is formed. The outer zone consisted of practically pure FeS; the intermediate zone was a solid solution of (Fe,Cr)S, partially decomposed to FeCr2S4 and metal during cooling; and the inner zone contained small Cr2O3 inclusions in an (Fe,Cr)S matrix.read more
Citations
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Proceedings ArticleDOI
Oxidation and Hot Corrosion of Superalloys
F. S. Pettit,Gerald H. Meier +1 more
TL;DR: In this paper, the properties of superalloys at temperatures above about 6OOC were examined and it was shown that the oxide reaction product barriers are stable upon the surfaces of super-alloys by considering how these oxide scales are formed and then how they are destroyed in use.
Journal ArticleDOI
Transition from oxidation to sulfidation of Fe-Cr alloys in gases with low oxygen and high sulfur pressures
TL;DR: In this paper, the kinetic boundary of oxidation-sulfidation is explained with the help of the Fe-Cr-O-S phase diagram and the assumption that Fe diffuses faster through the (Cr, Fe)2O3 solid solution than does Cr.
Journal ArticleDOI
Sulfidation properties of an Fe-26.6 at.% Cr alloy at temperatures of 973–1173 K in H2S-H2 atmospheres at sulfur Pressures 104–10−6 Pa
T. Narita,W. W. Smeltzer +1 more
TL;DR: In this article, the sulfidation properties of an Fe-26.6 alloy at 973, 1073, and 1173 K in H2S-H2 atmospheres at sulfur pressures 104⩾ ⩾ 10−6 Pa.
Journal ArticleDOI
Effect of cerium implantation on the corrosion of alloy 800H in an S-O-C environment
TL;DR: In this paper, the corrosion behavior of wrought austenitic Fe20Cr32Ni steel, Alloy 800H, was studied in a simulated coal gasification atmosphere at 700°C.
Journal ArticleDOI
Sulfidation properties of austenitic Fe-Mn and Fe-Mn-Al alloys under low sulfur vapor pressure (8 Pa) in the temperature range 873–1173 K
M. Perez,J. P. Larpin +1 more
TL;DR: The sulfidation properties of austenitic Fe-Mn and Fe-mn-Al alloys containing small amounts of carbon have been characterized with respect to the sulfidation kinetics, scale morphological development, structures, and composition of the sulfide phases as mentioned in this paper.
References
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Journal ArticleDOI
The thermochemistry of transition metal sulfides
TL;DR: A survey of the available data for the standard Gibbs energies of formation of solid and liquid sulfides of transition metals is given in this article, where the results are plotted as standard Gibbs energy vs temperature diagrams.
Journal ArticleDOI
Beitrag zur Theorie des Anlauf Vorganges. III
Carl Wagner,Karl Grünewald +1 more
TL;DR: The Oxydationsgeschwindigkeit von Zink zu Zinkoxyd is innerhalb unvermeidlicher Fehlergrenzen nicht merklich abhängig vom Sauerstoffdruck.
Journal ArticleDOI
High-temperature sulfur corrosion of iron-chromium alloys
S. Mrowec,T. Walec,T. Werber +2 more
TL;DR: In this article, the kinetics and the mechanism of sulfurization of Fe-Cr alloys containing from 0.35 to 74 at. % Cr were studied in the temperature range 700-1000°C. The reaction rate was determined by the continuous gravimetric method.
Journal ArticleDOI
Phase relations in the Fe-Ni-Cr-S system and the sulfidation of an austenitic stainless steel
TL;DR: In this article, the stability fields of various sulfide phases that form on Fe-Cr, Fe-Ni, Ni-Cr and Fe-cr-Ni alloys have been developed as a function of temperature and the partial pressure of sulfur.
Journal ArticleDOI
On the high-temperature corrosion of Fe-Cr alloys in sulfur vapor
Toshio Narita,Keizo Nishida +1 more
TL;DR: The mechanism of sulfidation of Fe-Cr alloys ranging from 8 to 97 wt.% chromium was determined from studies of scale structures, surface morphologies of scale, and reaction kinetics as mentioned in this paper.
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