摘要
对PM Al Li合金在高应变速率超塑性变形行为进行了研究 ,对其变形机制进行了讨论 .研究表明 ,PM Li合金在超塑变形过程中晶粒会发生形变诱发动态长大 ,其长大速率主要受应变速率所控制 ;在变形过程中 ,随着应变速率的增加 ,晶界滑动的协调机制由晶内位错滑移协调逐步向晶粒变形协调转变 :PMAl-Li合金在 5 70℃以上变形时 ,绝热加热现象的发生会导致液相的产生 ,并且液相的体积分数随应变速率的增加而增大 ,合金的延伸率随着液相体积分数的增加而急剧下降 .
The results of a high strain rate superplastic property and deformation mechanism of rapidly solidified PM Al-Li alloy have been reported. It is revealed that the deformation-induced continuous growth of grains can occur during deformation and the deformation strain rate controls the grain growth rate dominantly. With the increasing deformation strain rate, the accommodate mechanism of grain boundary sliding(GBS) changes from lattice dislocation sliding to grain shape changes by local shear deformation. During the high strain rate deformation above 570℃,liquid phase appears as a result of adiabatic heating and the total elongation decreases rapidly with the increasing fraction volume of liquid phase.
出处
《西安工业学院学报》
2001年第3期250-255,共6页
Journal of Xi'an Institute of Technology
