预置粒子对ZM6镁合金热变形组织及力学性能的影响

Effects of pre-existing particle on microstructural and mechanical properties of ZM6 magnesium alloy under hot compression

采用光学显微镜(OM)、扫描电子显微镜(SEM)、电子背散射衍射技术(EBSD)、透射电子显微镜(TEM)等分析预置粒子对ZM6镁合金热压缩过程中显微结构的影响,并在室温下进行室温力学性能测试。结果表明:预置粒子能够有效促进热变形过程中的动态再结晶行为,热压缩后合金组织细化、织构弱化,抗拉强度和伸长率都显著提升。和固溶态样品相比,预置粒子样品在510℃下再结晶体积分数由85%提升至100%,在不损害强度的前提下,伸长率提升至18.2%,提升了30%。

The effects of pre-existing particles on the microstructure of a ZM6 magnesium alloy during hot deformation were investigated by optical microscopy(OM),scanning electron microscopy(SEM),back-scattering diffractometry(EBSD),and transmission electron microscopy(TEM).The mechanical properties were detected through tensile tests at room temperature.The results show that dynamic recrystallization(DRX)is remarkably promoted during compression by the pre-existing particles.Accordingly,obvious grain refinement and basal texture weakening are observed after compression,resulting in improvement of ultimate tensile strength and elongation.Compared with the sample without pre-existing particles,the volume fraction of dynamic recrystallization increases from 85%to almost 100%,and the elongation of compressed sample with pre-existing particle treatment increases by 30%,reaching a maximum of 18.2%,without any drop in strength.