Effects of plastic deformations on microstructure and mechanical properties of ODS-310 austenitic steel

ODS-310 austenitic steel (Fe–25Cr–20Ni–0.35Y2O3–0.5Ti) was fabricated by the process of mechanical alloying and hot isostatic pressing. Plastic deformations, including forging and hot rolling, were applied to the as-hipped samples to improve the ductility. Microstructural evolutions in samples under different fabrication conditions were characterized by TEM. Tensile properties were tested at 23 °C and 700 °C. Dispersed oxide particles with sizes between 10 nm and 50 nm were characterized to be rich in Y–Ti–O. UTS and elongation of the as-hipped sample were 904 MPa and 11% respectively at 23 °C. Elongation increased two times after plastic deformations while there was only slight decrease in strength properties.

► We fabricated a 310 type ODS austenitic steel by the process of MA and HIP. ► Plastic deformations, including forging and hot rolling, were applied to samples. ► Fine Y-Ti-O particles dispersed in a relatively uniform way after forging. ► Ductility increased greatly after deformations, while strength decreased slightly.