TEM study of the effect of high-temperature thermal cycles on the stability of the Y-Al-O oxides in MA956 ODS steel

Abstract

MA956, a commercial ferritic grade of Oxide Dispersion-Strengthened (ODS) steel, was investigated using transmission electron microscopy (TEM) to evaluate the influence of high-temperature thermal cycles on the nanometric dispersed oxides. Analyses of the oxide size distribution were carried out on foils from the as-received MA956 and following treatment at 1285ºC for one hour, and show that growth of the oxides has occurred under the thermal cycle. Implications for the oxide stability in the steel matrix are discussed, in the light of the oxide chemical composition