Mo微合金化对铸态Mg_(94)Zn_(2.5)Y_(2.5)Mn_1合金显微组织和力学性能的影响

Effect of Mo Microalloying on Microstructure and Mechanical Properties of As-Cast Mg_(94)Zn_(2.5)Y_(2.5)Mn_1 Alloy

在Mg-Y-Zn系长周期镁合金中加入微量Mo,探究其微合金化对基体合金组织及力学性能的影响。结果表明,铸态Mg-Zn-Y-Mn-(Mo)合金显微组织由α-Mg基体相、18R LPSO相(Mg_(12)YZn)和W相(Mg_3Zn_3Y_2)三相组成。发现微量Mo能明显细化铸态合金晶粒,显著促进合金中18R LPSO相形成,抑制W相析出。当加入0.3 wt.%Mo时,合金的显微组织和力学性能达到最佳,最小晶粒尺寸达到22μm,其抗拉强度和伸长率分别达到265 MPa和13.5%。

Traces Mo was added to as-cast Mg-Zn-Y-Mn alloy to investigate the influence ofmicroalloying on microstructure and mechanical properties of matrix alloy. The results show that the as-cast Mg-Zn-Y-Mn-Mo alloys mainly consists of α-Mg matrix, 18R-LPSO phase （Mg12YZn） and W-phase （MgaZnaY2）. And traces Mo can greatly refine the grain of the as-cast alloy, increase the volume fraction of LPSO phase and inhibit the precipitation of W phase. With 0.3wt.% Mo addition, the alloy achieves the optimal microstructures and mechanical properties, the minimum grain size reaches 22 μm, with tensile strength of 265 MPa and elongation of 13.5%.