Effects of Gadolinium on Aging Behavior and Mechanical Properties of Mg-5Y-3Nd-Zr Alloy
Mg-5Y-3Nd-Zr-xGd (x=0 and 4 wt.%) alloys were prepared by metal mould casting, and aging behavior, mechanical properties and fracture morphology were investigated. The result shows that after T6 treatment, the massive eutectic phase in as-cast alloys dissolved and finer Mg5RE phase precipitated dispersively in the matrix, and mechanical properties were improved simultaneously. Mg-5Y-3Nd-4Gd-Zr alloy exhibits good age hardening behavior and the peak hardness is about 20% higher than the Gd-free alloy. Gd addition can significantly improve mechanical properties of the alloy especially at the elevated temperature. The ultimate tensile strength and yield strength of Mg-5Y-3Nd-4Gd-Zr alloy at 250°C, with the value of 276 and 168 MPa, respectively, are over 20% higher than those of the Gd-free alloy. It is mainly attributed to the increase and homogeneous distribution of the fine heat-resistant Mg5RE precipitate in the matrix.
Pengcheng Wang, Liqun Ai, Yungang Li, Xiaoming Sang and Jinglong Bu
L. D. Wang et al., "Effects of Gadolinium on Aging Behavior and Mechanical Properties of Mg-5Y-3Nd-Zr Alloy", Advanced Materials Research, Vols. 295-297, pp. 1183-1187, 2011