Exceptionally high strength and good ductility in an ultrafine-grained 316L steel processed by severe plastic deformation and subsequent annealing

An investigation was conducted to evaluate the effect of annealing at different temperatures on the tensile properties of ultrafine-grained 316L stainless steel processed by high-pressure torsion (HPT). A "moderate-temperature" annealing at 740 K resulted in reduced strength and elongation due to the annihilation of mobile dislocations. A "high-temperature" annealing at 1000 K yielded a remarkably good combination of yield strength (similar to 1330 MPa) and elongation to failure (similar to 43%) which can be attributed to the almost full reversion of alpha'-martensite formed during HPT into gamma-austenite while the grain size remained very fine with a value of about 200 nm. (C) 2017 Elsevier B.V. All rights reserved.