Precipitation and its effect on age-hardening behavior of as-cast Mg-Gd-Y alloy

Microstructures evolution of Mg-7Gd-3Y-0.4Zr (wt.%) alloy during aging at 200 degrees C was investigated by using optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results showed that the alloy could exhibit remarkable age-hardening response by optimum solid solution and aging conditions. Especially, the highest Vickers hardness (HV) of this alloy was obtained when it was aged at 200 degrees C for 120 h, which was mainly attributed to a dense distribution of beta' precipitation in the matrix. (C) 2010 Elsevier Ltd. All rights reserved.