Cyclic oxidation of yttria dispersed austenitic stainless steels

Cyclic oxidation of austenitic steels (Fe–20Ni–14Cr–2.5Mo–2Mn–2.5Al-wt.%) dispersed with 0, 0.5 and 5 wt.% yttria was carried out at 800 °C in air. The scale surface and cross-section were characterized using X-ray diffraction, scanning electron microscopy (SEM), electron probe microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS). Yttria additions improve the resistance to spallation. The increase in the resistance to spallation appears to be related to the presence of mixed oxides between yttria and base metal oxides.