High temperature corrosion behavior of alloys in reducing HCl and H2S containing environments: Thermodynamical and experimental assessment

High-temperature corrosion mechanisms in reducing atmospheres containing HCl (3.8 vol%) and a varying amount of H2S (0.02 –2 were developed for several alloys between 420°C 680°C. These are mainly based on practical observations kinetic considerations—and less thermodynamic data. This is due to the complexity these mixed gas atmospheres, volatile products, ever-changing conditions within layer, which made it not possible predict calculate actual zone. In this article, detailed analysis previously achieved experimental presented. Correlations deviations calculations findings stated discussed. The behavior ferritic K90941, performs worse than corrosion-resistant austenitic alloys, except one test condition at 580°C atmosphere with 0.2 vol% H2S, explained supported by By combining experiments thermodynamics, H2S-containing explained.