AZ31镁合金温变形对其性能影响的研究

Effect of warm forming on the mechanical properties of AZ31 magnesium alloy

为了研究温变形对铸态AZ31镁合金力学性能的影响,在210-300℃温度范围内对均匀化后的合金进行了不同程度的平面应变压缩,并根据微观组织的演变对其进行了分析．结果表明:随变形温度的升高,在相同的变形程度下晶粒有长大的趋势,其抗拉强度增量下降;在同一温度下变形,强度增量随着变形程度的增加而增大,变形到一定程度时,呈现减小的趋势．在210℃下变形,当ε达到2．07时,其抗拉强度最大可达 305MPa,较铸态提高近50％．表明AZ31合金温变形时,通过形变强化与细晶强化的合理组合,可获得细小均匀的等轴组织,大幅度提高镁合金的强度．

Plane strain compression tests of different degrees of deformation at temperatures ranging from 210 to 300℃ were carried out for ascast AZ31 magnesium alloy. The effect of warm forming on mechanical properties of AZ31 alloys was studied and analyzed according to the microstructure evolvement. Results showed that, at the same degree of deformation, the increment of tensible strength decreases with increasing temperature because the crystal grain becomes coarse ; at the same temperature, the increment of tensible strength increases, gradually at first, with an increasing degree of deformation, but slightly decreases at a certain degree of deformation. High strength of 305 MPa was attained for AZ31 alloy at 210℃ when is 2.07. Compared with as - cast alloys, tensible strength enhanced about 50%. This suggests that fine grain and high strength are attained for AZ31 alloy by means of rational combined action of work hardening and fine grain strengthening during warm forming.