This presentation summarizes the development and expansion of a comprehensive information system for corrosion of metals and alloys in high temperature gases. New insights in analysis of thermochemical data for the Fe-Ni-Cr-Co-C-O-S-N system are being compiled. Corrosion mechanisms emphasized are oxidation, sulfidation, sulfidation/oxidation, and carburization.
A laboratory study was performed by exposing seven candidate heat exchanger alloys to simulated 2 (sCO2) Brayton power cycles. The alloys, consisting of fineirtriaitilcly s 3te.6e%ls ,O austenitic stainless steels, and nickel-base alloys, were exposed to impure CO2 containing 2 and 5.3% H2O at a constant pressure of 200 bar.
Titanium does not show the required mechanical strength for high temperature high pressure applications and it can only be used to form liners for an SCWO apparatus. Therefore, pressure tubes made of alloy 625 were lined with titanium grade 2, Additionally corrosion tests with coupons made of titanium grades 2, 5, 7, 12 and P-C were performed.