压铸Mg-3Nd-0.2Zn-0.4Zr合金的组织和力学性能研究

Study on Microstructure and Mechanical Properties of Mg-6Gd-3Y-0.5Zr Alloy Processed by Die-Casting

采用压铸成形工艺,研究了Mg-3Nd-0.2Zn-0.4Zr(NZ30K)合金压铸组织和力学性能。研究表明,通过压铸制备的NZ30K合金组织中初生α-Mg相晶粒均匀细小,平均尺寸为25~35μm左右。压铸NZ30K合金组织由α-Mg基体和晶界处的离异共晶Mg12Nd相及Mg4Zn7相组成。铸态压铸NZ30K合金屈服强度、抗拉强度和伸长率分别为119 MPa、186.7 MPa、10.04%。采用正交实验方法研究了固溶温度和保温时间对压铸NZ30K合金组织和力学性能的影响,结果表明固溶温度为540℃、固溶时间为3 h时,该合金可获得较好的力学性能。

Microstructures and mechnical properties of Mg-3Nd-0.2Zn-0.4Zr(wt. %)( NZ30K)alloys with die casting were investigated. The results show that the grain is fine and size of primary α-Mg in die casting is in the range of 25-35 μm of NZ30 K alloy. The microstructure of NZ30 K alloy consists of α-Mg, Mg12 Nd and Mg4Zn7 particles distributed along the grain boundaries. The yield strengths(YS), ultimate tensile strength(UTS) and elongation of as-cast NZ30 K alloys are 119 MPa, 186.7 MPa and 10.04% respectively. The effects of solution temperature and solution time on the microstructure and properties of NZ30 K alloys were studied by orthogonal test.The results indicated the optimum scheme as follows: the temperature of solution treatment was 540 ℃,solution time 3 h.