(1. 江苏大学 材料科学与工程学院，镇江 212013;
2. 上海交通大学 密西根学院，上海 200240;
3. 江苏理工学院 机械工程学院，常州 213000)
摘 要: 采用预固溶或预时效+LSP形变+后时效处理方法，研究预固溶或预时效以及后时效处理对激光冲击AZ80镁合金组织参数(孪晶和析出相)的影响。结果表明:预固溶+激光冲击强化(LSP)形变处理使LSP强化层内产生高密度孪晶的形变带，离冲击表面越近，孪晶密度越高;经(170 ℃, 16 h)时效处理后，由于残余压应力热稳定性，预固溶+LSP形变强化层仍产生具有高密度孪晶的形变带;同时，弥散析出大量的颗粒状β-Mg17Al12相，优先在应力集中的形变带、孪晶界面和孪晶片层内析出;预时效析出的高密度β相极大地降低冲击强化层孪生产生率，孪晶体积分数明显降低，这是由于LSP诱导的高密度位错和析出相引起的。
关键字: AZ80镁合金;激光冲击强化;固溶;时效;孪晶;析出相
（1. School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, China;
2. Joint Institute, University of Michigan- Shanghai Jiao Tong University, Shanghai 200240, China;
3. School of Mechanical Engineering, Jiangsu University of Technology, Changzhou 213000, China）
Abstract:The effect of pre-solution, pre-aging and post-aging on microstructure parameters (twins and precipitates) of laser shocked AZ80 magnesium alloy was investigated by pre-solution or pre-aging+LSP deformation+post-aging. The results show that the deformation band with high density twins in the strengthened layer is produced by the treatment of pre-solution+laser shock processing(LSP) deformation, and the twins density increases with decrease of the distance to the impacted surface. The deformation band with high density twins is still produced by treatment of aging treatment for 16 h under the temperature of 170 ℃ due to the stability of the residual compressive stresses. At the same time, a large number of granular β-Mg17Al12 phases are dispersively and preferentially precipitated in the deformation band, the twin interface and the twin lamellae where the stress concentration exists. The ratio of twinning in the strengthened layer is greatly reduced by the high density β phase precipitated from the pre-solution, and the volume fraction of the twins is decreased significantly, because of the high density dislocation and precipitates induced by LSP.
Key words: AZ80 magnesium alloy; laser shock processing; solution; aging; twins; precipitate
