Deformation mechanisms in ultrahigh-strength and high-ductility nanostructured FeMnAlC alloy

Abstract

The deformation mechanisms of a bulk nanostructured Fe-30Mn-9.5Al-2.0C (in wt.%) alloy were investigated. After aging at 450 degrees C for 9-12 h, the alloy exhibits an exceptional strength-ductility combination (e. g. yield strength similar to 1406 MPa with elongation similar to 32%). The aged alloy exhibits a novel microstructure with isolated austenite nano-channels bounded by an extremely high volume fraction of directional nano-sized (Fe,Mn)(3)AlC carbides (kappa'-carbides). The plastic deformation was found to be dominated by bursting dislocation nucleation within the isolated austenite nano-channels. (C) 2013 Elsevier B. V. All rights reserved.