低相变阈值金属高压加载下的相变层裂特性

Phase transition and spalling behavior of metal with low transition stress under high pressure

采用激光速度干涉仪(VISAR)和X光联合测试技术,在冲击压力远高于相变应力加载下,实验研究低相变阈值金属FeMnNi合金的相变层裂特性,结果发现等厚对称碰撞加载下FeMnNi合金出现反常的层裂行为。针对该反常的层裂行为,利用塑性波、相变波、稀疏波和逆相变引发的稀疏冲击波的相互作用过程进行分析,结果表明,该实验状态下FeMnNi合金样品存在相变和逆相变行为,逆相变引发的稀疏冲击波是导致反常层裂行为的主要因素。

VISAR and X-ray were adopted and the FeMnNi alloy specimens were subjected to the shock pressure far beyond the induced phase transition pressure. Abnormal spalling behaviors were observed in the FeMnNi alloy specimens under symmetric and same thickness impact. These abnormal spalling behaviors were analyzed by the interaction among plastic wave, phase transition wave, release fan wave and rarefaction shock wave induced by reverse phase transition. Results show that phase transition and reverse phase transition occur in FeMnNi alloy, and the rarefaction shock wave induced by reverse phase transition is a main factor to result in the abnormal spalling phenomenon.