镁合金孪生机理研究进展

Research Progress of Twinning Mechanism in Magnesium Alloys

镁合金是最轻的金属结构材料,其使用对减轻机件自重、节能减排有重要意义。但是,由于存在室温塑性差、拉压不对称、各向异性等缺点,其应用受到很大的限制。孪生在镁合金的塑性变形及使用性能方面扮演着重要的角色,但是其机理至今没有得到完全的确认。本文介绍了到目前为止关于密排六方金属孪生的几个理论模型,分析了各自的优缺点,指出今后可能的研究重点。

The applicaction of magnesium alloys as a key structural material for weight saving in automotive and aeronautic components had increesing important meanings because they were very light.Due to the poor low-temperature formability,asymmetry of tensile and compressive properties and strong levels of anisotropy,the application of magnesium alloys was restricted.Twinning played an imptant role in the machining process and had big effects on the final performance of materials.But up to now,the twinning mechanism was not fully understand.Several models discribing the mechanism of twinning in hcp metals were introduced,and the advantages and disadvantades of each model were analyzed.The possible research focus in the future were suggested.