Keizo Nishida

High-temperature sulfidation of Fe-Mn alloys

The complete range of binary Fe-Mn alloys were sulfidized in pure sulfur vapor (1 atm) at 700–1000°C. It was found that the corrosion kinetics could be divided into four groups, depending upon the alloy concentration. The first group, up to 11 w/o Mn, had a constant corrosion rate. The second group, up to about 63 w/o Mn, had an exponentially decreasing rate of corrosion with increasing manganese content. In the third group, about 63–80 w/o Mn alloys, the corrosion rate did not follow the parabolic law. The corrosion rates became constant above 80 w/o Mn. These corrosion kinetics were explained by considering the scale structure and alloy substrate.

Sulfidation properties of Fe-Cr alloys at 1073 K in H2S-H2 atmospheres of sulfur pressures 10−2 and 10−5 Pa

AbstractAn investigation is reported on the sulfidation properties of Fe-Cr alloys over their complete compositional range in H2S -H2atmospheres at 1073 K. Sulfidation of alloys containing less than 60 at. % Cr obeyed parabolic kinetics and alloys of larger chromium content and chromium followed linear kinetics. Scales were composed of two distinct layers: an outer columnar grained sulfide and an inner equiaxed grained sulfide layer of increased relative thickness and porosity at larger alloy chromium contents. The scales on quenched specimens were composed of either (CrFe)5S6or (FeCr)S plus small amounts of (FeCr)3S4at

High-temperature corrosion of low Cr-Fe alloys in sulfur vapor

P_{S_2 }

Oxidation properties of Co-Mn alloys at temperatures from 1273 to 1473 K

=10−2Pa and of (CrFe)5S6at

Sulfidation kinetics and scale structures of chromium at temperatures of 973-1173 K and 104−10−6 Pa sulfur pressures

P_{S_2 }

Interdiffusion in the ζ-Solid Solution of a Ni–Al System

=10−5Pa. Internal sulfidation was most pronounced in the high chromium content alloys and at the low sulfur pressure. The parabolic sulfidation rate at