Improving age hardening response and mechanical properties of a new Mg-RE alloy via simple pre-cold rolling

In this study, a new preparation method is designed to simultaneously realize the light weight and high strength efficiently for magnesium (Mg) alloys. The alloy design concept is based on the multi-rare earth alloying and particularly the combined processes of pre-cold rolling and ageing treatment. Here the influence of pre-cold rolling prior to ageing treatment on microstructure evolution and mechanical properties of solution treated Mg alloy with a moderate RE content (similar to 7 wt%, RE = Gd, Y, Nd, Ho, Er) is systematically investigated. The non-cold rolled alloy exhibits an age-hardening response and improved tensile strength via beta '' precipitates due to multi-rare earth alloying. A simple pre-cold rolling introducing dislocations can further improve the efficiency of age hardening and tensile strength. The enhanced tensile strength of pre-cold rolled + peak-aged alloy is mainly attributed to the combination effects of fine and dense beta '' prismatic precipitates, basal SFs and dislocations. (C) 2018 Elsevier B.V. All rights reserved.