等径道角挤压制备高力学性能细晶Mg-6Al合金

为了制备高力学性能细晶Mg-6Al合金坯料,采用金相显微镜、材料拉伸实验机等手段对Mg-6Al合金铸坯进行等径道角挤压实验研究.并利用热处理工艺对挤压后材料进行处理,研究热处理工艺参数对材料力学性能的影响规律.结果表明,Mg-6Al合金的铸坯的抗拉强度为196.4MPa,延伸率为12.6%.经过等径道角挤压的Mg-6Al合金坯料的晶粒被大大细化,其晶粒尺寸由铸坯的140μm左右细化到8μm左右.其力学性能有很大提高,抗拉强度由196.4MPa提高到308.2MPa;延伸率由12.6%提高到30.6%.等径道角挤压工艺是一种非常好的制备高力学性能、细晶Mg-6Al合金的工艺方法.固溶和人工时效热处理工艺对等径道角挤压的Mg-6Al合金坯料的强度有较大影响,对延伸率影响较小.

Preparing Mg-6Al alloy with high mechanical properties and fine grains by equal channel angular extrusion

In order to prepare Mg-6Al alloy with high mechanical properties and fine grains,equal channel angular extrusion(ECAE) process of Mg-6Al alloy was investigated by metalloscope and tensile test machine of material.Billet processed by ECAE was heat treated and influence of technological parameters on mechanical properties also was studied.The results show that tensile strength and elongation of as-cast Mg-6Al alloy are 196.4 MPa and 12.6%,respectively.After as-cast Mg-6Al alloy was extruded by ECAE,grain size was refined from 140 μm to 8 μm,and mechanical properties of billets were increased greatly.Ttensile strength was increase from 196.4 MPa to 308.2 MPa.Elongation was increased from 12.6% to 30.6%.EACE is a good method for refining microstructure and enhancing mechanical properties.Solid solution and aging has an influence on tensile of Mg-6Al alloy processed by ECAE,but little influence on elongation.