摘要
利用高压电镜和金相显微镜对7475高强铝合金超塑变形中的空洞形核问题进行了研究。结果表明空洞主要形成在超塑变形过程中,而不是形核于形变热处理中。空洞形核的主要原因是晶界滑移在晶界不平整处受阻,产生应力集中。
The cavity nucleation in the process of superplastic deformation of high strength aluminium alloy was studied by means of high-voltage electron microscopy and metallographic microscopy.The results show that cavities are nucleated mainly in the process of superplastic deformation but not in thermome-chanical process. The main cause for cavity nucleation is the high stress concentration due to the grain boundary slip hindered at uneven grain boundary.
关键词
铝合金
超塑变形
空洞形核
superplastic deformation,cavity nucleation, 7475 Al alloy.
