Microstructure and Mechanical Properties of a Mg-Sm-Gd-Zn-Zr Alloy Processed by Heat Treatment

The microstructure and mechanical properties of high performance Mg-2.6Sm-1.3Gd-0.6Zn-0.5Zr (wt.%) alloy was investigated. The alloy was mainly composed α-Mg and (Mg,Zn)3(Sm,Gd)1 eutectic phase in the as-cast state. After solution treatment at 510 °C for 4 h and subsequent aging at 200 °C, the alloy exhibited remarkable mechanical properties. The ultimate tensile strength, yield strength and elongation of the alloy at peak-aged state were 282, 185 MPa and 6.1% at room temperature. These good mechanical properties were mainly attributed to the fine microstructure and fine metastable phase precipitates in the matrix during aging at 200 °C for 32 h. © 2014 Springer Science+Business Media New York and ASM International.