( 1. 中南大学 材料科学与工程学院,长沙 410083;
2. 中国兵器科学研究院 宁波分院轻质材料研究所, 宁波 315103)
摘 要: 综述了镁及镁合金动态再结晶方面的研究现状, 介绍了镁及镁合金室温或高温塑性变形行为, 包括应力—应变特征及其影响因素、 应变速率方程和流变应力方程; 描述了该合金在不同变形条件下发生塑性变形时的位错、 孪晶、 亚结构等微观组织演变以及各种动态再结晶如孪生动态再结晶、 低温动态再结晶、 连续动态再结晶、 不连续动态再结晶和旋转动态再结晶的机理及其特点; 最后讨论了动态再结晶与塑性变形之间的相互关系, 并提出了镁及镁合金动态再结晶研究的发展趋势。
关键字: 镁合金;力学行为;微观结构演变;塑性变形;动态再结晶
dynamic recrystallization in
pure magnesium and its alloys
( 1. School of Materials Science and Engineering,
Central South University,Changsha 410083, China;
2. Light Materials Institute, Ningbo Branch of Enginery Science Academy of China,Ningbo 315103, China)
Abstract: Some aspects of present research on dynamic recrystallization in pure magnesium and its alloys were reviewed. The mechanical behaviors, including stress—strain characteristics, strain rate equation and flow stress equation, during plastic deformation at ambient or elevated temperatures were discussed in detail. The evolution of dislocation, twinning and substructure during plastic deformation under different conditions was also discussed. The mechanisms and characteristics of dynamic recrystallization(DRX) such as twinning DRX, low temperature DRX, continuous DRX, discontinuous DRX and rotation DRX, the correlation between plastic deformation and DRX as well as the research prospect on DRX in pure magnesium and its alloys were summarized or proposed.
Key words: magnesium alloy; mechanical behavior; microstructure evolution; plastic deformation; dynamic recrystallization