Enhancement of the strain hardening ability in ultrafine grained Mg alloys with high strength

Two thermo-mechanical processing methods involving severe plastic deformation (SPD) are proposed for the development of a novel microstructure having nanosized Mg17Al12 (beta) particles distributed within the interiors of ultrafine grains in Mg-Al based alloys. The first method involves deformation-induced break-up of the beta phase during SPD, while the second method involves low temperature dynamic precipitation during SPD followed by low temperature aging. The resulting processed materials exhibited very high yield strengths of over 380 MPa and distinct strain hardening properties. (c) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.