Formation of Nano/ultrafine Grain Structure in a Ti-modified 201L Stainless Steel through Martensite Thermomechanical Treatment

Abstract

The formation of nano/ultrafine grain structure in a Ti-modified 201L austenitic stainless steel using the martensite thermomechanical treatment was investigated. Effects of Ti micro-alloy addition on the formation of strain-induced martensite (SIM) during cold rolling and austenite reversion during subsequent annealing were studied. The results showed that the nano-grained Ti-modified 201L steel with the average grain size of 45 nm possessed the yield strength of 1000 MPa, ultimate tensile strength of 1330 MPa and total elongation of 42%. Such improvement in mechanical properties of the thermomechanically processed steel is believed to be due to the formation of SIM supplemented with precipitation of Ti carbides.