镁锂合金热加工图建立和塑性失稳因素的研究

Research on the Effecting Factors of Plasticity Instability and Processing Maps of Mg-Li alloys

通过对LAZ532镁锂合金在125-250℃,应变速率为10^-4-10^-1s^-1条件下拉伸变形行为研究.构建LAZ532镁锂合金失稳图和加工图.研究结果表明：在变形温度低于180℃时合金出现塑性失稳,导致塑性失稳的主要原因是变形孪晶;合金较适宜加工区域为变形温度（t）220℃,应变速率0.001 s^-1处,该区域的功率耗散效率较高,合金能发生动态再结晶,并具有较好的塑性.

The deformation behavior of LAZ532 magnesium lithium alloy was investigated by tensile tests from 125 ℃ to 250 ℃,and the strain rate was from 10 %1 to 10 %、The instability map and processing maps were drawn according to the dynamic material model.The results showd that plastic instability were identified with temperature below 180℃. This plastic instability was caused by the deformation twins. The optimal processing temperature and strain rate of hot deformation under the test condition were 220 ℃ and 0.001 s ^-1 The power dissipation of the alloy was higher, and the alloy was fully recrystallized and exhibited superior ductility.