(1. 重庆理工大学材料科学与工程学院，重庆400054；
2. 重庆理工大学重庆市高校模具技术重点实验室，重庆400054)
摘 要: 利用 孪晶结构调控镁合金织构和组织，可作为开辟一条低成本生产高性能镁合金的路径。探索 形变孪生新的特点和规律，揭示 孪生变形的物理本质是利用 孪生变形调整镁合金组织和性能的关键。对国内外学者应用孪生晶体学理论、分子动力学计算机模拟和透射电镜等研究手段探索 形变孪晶长大机制进行综述。重点对 孪晶界面精细结构以及 孪晶长大机制(孪生位错剪切机制和曳步机制)进行总结与评述。针对目前国内外学者在 孪生机制中存在的重大争议，有必要丰富实验研究及计算机模拟结果，进一步探索 孪生长大机制，从而为利用 孪晶调控镁合金力学性能的研究奠定理论基础。
关键字: 镁合金；密排六方金属； 孪晶界；孪生
（1. School of Materials Science and Engineering, Chongqing University of Technology, Chongqing 400054, China;
2. Chongqing Municipal Key Laboratory of Institutions of Higher Education for Mould Technology
Chongqing University of Technology, Chongqing 400054, China）
Abstract:twining can change the texture and microstructure of Mg alloys, opening up a low-cost production of high performance magnesium alloys. The new characteristic and law are explored, and it is important to uncover the characterizations and the physical nature of twinning. The twinning mechanisms investigated by twinning crystallographic theory, atomic-computer simulation and high resolution transmission electron microscopy, were reviewed. The morphology and microstructure of twin and twinning mechanism (dislocation mechanism and shuffling mechanism) were summarized and discussed. As for the controversy between the dislocation mechanism and the shuffling mechanism, it is necessary to enrich the experimental results and atomic-computer simulation. Further exploring twinning growth mechanism is a theoretical foundation for utilizing twins to tailor the microstructure and mechanical properties of Mg alloy.
Key words: Ag alloy; hexagonal close packed metals; twinning boundary; twinning mechanism
