Strengthening austenitic steels by using nanotwinned austenitic grains

A novel strategy for strengthening austenite steels is introduced by using the unique strengthening effect of nanoscale twins. Austenite grains containing multiple nanoscale twins can be strengthened to a yield strength of a few GPa with very high work-hardening rates. Compared with the conventional dual-phase steels, several austenite steels strengthened by using ultra-strong nanotwinned austenite grains exhibit a superior strength-ductility synergy. Perspectives on future development of the nanotwinned austenite steels and the nanotwin strengthening strategy are presented. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.