(1 北京科技大学新金属材料国家重点实验室，北京 100083; 2 北京理工大学，北京 100022)
摘 要: 单相Al-2Mg合金在300~530℃ 以0.069~1.587s-1形变速率扭转到真应变5.5， 随后立即水冷。 采用真应力-真应变曲线，偏振光金相和透射电子显微镜研究该合金热扭转过程的动态复原机制。试验证实，该合金热扭转过程中发生了动态再结晶，但在一定的Z 参数范 围内发生，Z 参数过大或过小，只发生动态回复。显微组织分析并没有发现层错的存在。发生动态再结晶的原因是动态回复被抑制，即在较高形变温下，加大形变速率，而在较低形变温度下，降低形变速率。
关键字: Al-2Mg合金；动态再结晶；热扭转
（State Key Laboratory for Advanced Metals and Materials,
University of Science and Technology Beijing, Beijing 100083, P.R.China
Beijing Institute of Technology，Beijing 100022，P.R.China）
Abstract:Specimens of single phase Al-2Mg alloy have been deformed by hot torsion at 300~530℃ and strain rates of 0.069~1.587 s-1 to true strain of 5.5 followed by water quenched immediately. The dynamic restoration mechanisms during hot torsion were examined by the true stress-true strain curves，optical and electron microscopy. It has been shown that dynamic recrystallization occurs in certain range of parameter Z. If Al-2Mg alloy is deformed by torsion out of the range， only dynamic recovery occurs. The microstructural observations indicate that there are not the regions of stacking faults in the matrix. The occurrence of dynamic recrystallization results from the depression of dynamic recovery，i. e. increasing strain rate at higher temperature and reducing strain rate at lower temperature.
Key words: alaminium-magnesium alloys；dynamic recrystallization；hot torsion tests
