中文摘要：

采用VISAR测量样品自由面速度剖面和回收样品观测分析联合技术,开展等厚对称碰撞实验,结合文献中的实验结果,研究了冲击加载压力大于纯铁材料冲击相变阈值约2-5 GPa和大于冲击相变阈值约10 GPa两种压力状态下纯铁材料的加卸载历程及各相区的变化,并从应力波相互作用的角度,指出了冲击加载压力略大于纯铁材料相变阈值约2 GPa时,等厚对称碰撞样品＂反常＂二次层裂与冲击相变及逆相变的关联机制。

英文摘要：

By means of VISAR and metallography,phase transition and saplling behavior in pure iron under the given pressure were studied through symmetric and same thickness flyer/sample experiments.In combination with the experimental results from references,and the loading and unloading histories and phase structure in iron sample are obtained.The given pressure are beyond the phase transition pressure of 13 GPa about 2-5 GPa and 10 GPa,respectively.Abnormal multiple saplling behavior happens in the pure iron sample as the impact pressure beyond the phase transition pressure of 13 GPa about 2 GPa.From the interaction process of stress waves,the contacting mechanism among the spalling behavior and the phase transition and the reverse phase transition have been studied.