中文摘要：

材料在塑性状态下拉伸变形,存在载荷失稳和几何失稳两种失稳形式。对于既有应变强化又有应变速率强化的材料,载荷失稳与几何失稳并不同时发生,且失稳应变主要受材料性能参数的控制。高温拉伸变形的Cr15Mn9Cu2Ni1N奥氏体不锈钢,表现出明显的应变速率敏感性,使得载荷失稳与几何失稳不同时发生,几何失稳前的均匀变形量明显增大;随变形温度升高,应变速率敏感性系数增大,几何失稳应变也随之增大。

英文摘要：

There are load instability and geometric instability two instability forms during tensile deformation. For the materials of strain-hardening and strain rate sensitivity, the load instability and geometric instability does not occur at the same time, and the instability strains are mainly controlled by material parameters. Cr15Mn9Cu2Ni1N austenitic stainless steel has remarkably strain rate sensitivity, and it makes load instability and the geometric instability does not occur at the same time, and the geometric instability strain increases. The strain rate sensitivity coefficient increases with the increase of deformation temperature, which can make geometric instability strain increase.