Effects of Grain Size and CeO2 Addition on the Corrosion Behaviour of Cr2O3 based Ceramics in High Temperature Supercritical Water Environment

Abstract

In this investigation, Cr₂O₃ ceramics with different grain sizes were prepared and tested in supercritical water (SCW) environment at 650°C /25 MPa for 200 hours. The results show that the stability of Cr₂O₃ in SCW was affected by its grain size. In addition, various amounts of CeO₂ were added to Cr₂O₃ to examine the effect of CeO₂ on the corrosion behaviour of the Cr₂O₃ based ceramic under SCW condition. These Cr₂O₃-based ceramics were exposed to an SCW environment at 650°C/ 25 MPa for up to 600 hours. The results showed that adding a proper amount (≤ 5 wt. %) of CeO₂ increased the corrosion resistance of Cr₂O₃-based ceramics in SCW.