On cooling rate dependent spallation behavior of α-alumina scale grown by oxidation

It is hypothesized that dynamic and non-uniform plastic relaxation occurs in α-Al2O3 scale on Fe-Cr-Al substrate during cooling from high temperature, and furthermore, that the non-uniformity of plastic relaxation is related to (1) the variation of residual stress with respect to cooling rate; and (2) the rate of stress relaxation. Based on this hypothesis, a mechanical model is developed which gives accurate predictions for the cooling dependent spallation behavior of α-Al2O3 grown by oxidation.