Microstructure and mechanical property of Mg–2.0Ga alloys

Four alloying principles of magnesium alloys are reported and Mg–2.0 (at.%) Ga alloys are investigated. The results show that microstructure of solution treatment Mg–2.0Ga alloy consists of α-Mg dissolved Ga element and intermetallic compound Mg5Ga2 distributed discontinuously at grain boundary. After aging for 128 h a quantity of tiny Mg5Ga2 precipitates with Ø50 nm present homogenously in α-Mg of which the crystal parameters (especial c/a) is lower than those in pure Mg. And tiny α-Mg grains with 100 nm are observed in Mg–2.0Ga alloy aged for 128 h. The ultimate tensile strength, yield strength and elongation of Mg–2.0Ga alloys aged for 0.5 h and 128 h are 180.939 MPa and 196.85 MPa, 107.405 MPa and 150.898 MPa, and 8.19815% and 4.69937%, respectively. The results show that the principles are effective.