Paper: Effect of aging process on steam oxidation behaviour of austenitic steels Super 304H and HR3C

The aim of this work was to evaluate effect of aging process on steam oxidation resistance of Cr rich steels with around 18 wt % (Super 304H) and around 25 wt % (HR3C). The samples are still under exposure, however the results after 100, 200, 500 and 1000 h are available (the whole test is planned for 10 000 h). The effect of aging process on steam oxidation after first 1000 h showed the formation of a thinner oxide scale in contrast to the samples exposed in steam atmosphere only. Further, it was found, fine grain structure determine lower mass gain of the sample exposed in steam oxidation process, but in air oxidation process mass gain is mainly governed by Cr content in metal matrix. The post exposed analyses in this work were carried out using Scanning Electron Microscopy (SEM) supported by Energy Dispersive X-ray Spectroscopy (EDS) using X-Ray mapping function.

Automated summary

This study aimed to evaluate the effect of aging on steam oxidation resistance of Cr rich steels with different chromium content. The results showed that aging process led to thinner oxide scale formation and lower mass gain in sample with fine grain structure during steam oxidation, while mass gain in air oxidation was mainly governed by Cr content in metal matrix. Post-exposure analyses were conducted using SEM and EDS with X-ray mapping.