Pure Fe3Al and Fe3Al+4%Cr alloys were corroded at 1000 °C for up to 200 h in N2-0.1%H2S-mixed gas in order to study their corrosion behavior in H2S-containing atmosphere. The formed scales consisted primarily of α-Al2O3, FeAl2O4, and Fe2O3. In these oxide scales, hydrogen and sulfur dissolved according to the reaction; H2S→2H+S. Corrosion products of Cr were not identified in the scales from the XRD analysis, indicating that Cr dissolved in the oxide scales. Fe3Al+4%Cr alloy displayed poorer corrosion resistance than Fe3Al alloy, indicating that chromium accelerated the corrosion rates of Fe3Al alloys.

ZK60 alloy strip with 3.5mm thickness which produced by Twin Roll Casting (designated as TRC in short) was used in this paper. The effect of sequential annealing on microstructure and damping capacity of TRC ZK60 alloy was studied by using optical microscope (OM) and dynamic mechanical analyzer (DMA). The dendrite structure was present in TRC ZK60 alloy strip before and after annealing heat treatment. A few of recrystallized grains were present after annealed at 400°C for 1hr. The damping capacity of the strip as annealed at 400°C was better than that of annealed at the lower temperature. The room temperature (25°C) damping values (Q-1) of ZK60 strip which was annealed at 300°C, 350°C and 400°C were 0.0079, 0.0085 and 0.0096, respectively. The damping peak P1 is a relaxation process, but the damping peak P2 is not a relaxation process. The activation energy H for P1 of TRC ZK60 strip after annealed at 400°C for 1hr was 114KJ/mol. The damping peak P1 was attributed to boundary slip controlled by grain boundary diffusion and lattice self-diffusion.