铝含量对粉末冶金制备镁铝锆合金组织和力学性能的影响

摘要

Mg-xAl-1.5Zr alloys（x=0,2,4,6,8,mass fraction/%） were prepared by powder metallurgy technology.The effects of Al contents on microstructure and mechanical properties of the alloys were studied.The results show that Mg-Al-Zr alloys consisted of α-Mg matrix,Zr particles,β-Mg17Al12 phase and some microporosities.Increasing the Al content resulted in microstructure homogenizing of the alloys.Mg-6Al-1.5Zr had the highest microhardness and bending strength,up to 79.7 HV and 224 MPa,but its plasticity was poor,and the fracture showed a characteristic of quasi-cleavage fracture.%运用粉末冶金工艺制备了Mg-xAl-1.5Zr（x=0,2,4,6,8,质量分数/%）合金,研究了铝含量对其组织和力学性能的影响。结果表明：镁铝锆合金主要由α-Mg基体、锆颗粒、β-Mg17Al12相组成,还存在一些微小的孔洞;铝含量的增加使合金组织趋于均匀化;Mg-6Al-1.5Zr合金具有最高的硬度和抗弯强度,分别为79.7HV和224MPa,但其塑性较差,断口呈准解理断裂的特征。