MICROSTRUCTURAL OBSERVATION AND TENSILE ISOTROPY OF AN AUSTENITIC ODS STEEL

Based on a composition of 99.4 wt% AISI 316L stainless steel, 0.3 wt% Ti and 0.3 wt% Y2O3, an austenitic ODS steel was fabricated by a process of mechanical alloying, hot isostatic pressing and rolling. Fine oxide particles were observed in the matrix, and their chemical formulations were determined to be Y2Si2O7 and TiO. Heat treatment of the cold-rolled sample at 1200°C induced an isotropic tensile behavior at room temperature and at 700°C This result would be mainly attributed to the equiaxed grains that form as a result of the heat treatment for recrystallization.