Fig. 1. Initial configuration of the simulation system: (a) The equilibrated atomic configuration, and the arrow denotes the direction of impact; (b) the internal distribution of SFT.模拟初始构型　(a) 整体构型, 箭头方向代表冲击方向; (b) 模型中的层错四面体分布

Fig. 2. Snapshots of SFT formation.SFT的形成过程

Fig. 3. Relationship between particle velocity U_p and spall strength of perfect Cu and Cu with SFT. 不同U_p对应的层裂强度分布图

Fig. 4. Snapshots of SFT configuration and dislocation evolution at different deformation stages during shock compression: (a) U_p = 0.5 km/s; (b) U_p = 0.75 km/s. The rose red line represents the stair-rod dislocation, the green line represents the Shockley partial dislocation, the light blue line represents the Frank partial dislocation, and the red line is the undefined dislocation. 压缩过程中SFT的演化形态图及对应的位错演化图(其中, 玫红色线是压杆位错, 绿色线是Shockley不完全位错, 浅蓝色线是Frank不完全位错, 红色线是其他位错)　(a) U_p = 0.5 km/s; (b) U_p = 0.75 km/s

Fig. 5. Atomic configuration in Cu crystal during shock compression and tension at different impact velocity: (a) U_p = 0.75 km/s; (b) U_p = 1.25 km/s. 不同冲击速度下单晶铜在压缩和拉伸过程中的微结构演化图　(a) U_p = 0.75 km/s; (b) U_p = 1.25 km/s

Fig. 6. Void and dislocation evolution during spallation at U_p = 0.75 km/s: (a) Perfect crystal Cu; (b) Cu with SFT. U_p = 0.75 km/s时孔洞演化图像及位错分布图　(a) 完美单晶铜; (b) 含SFT铜

Fig. 7. Stress and temperature profiles for single crystal copper at U_p = 0.75 km/s: (a) Stress; (b) temperature. U_p = 0.75 km/s时孔洞演化对应的应力温度分布图 (a) 应力; (b) 温度

Fig. 8. Free surface velocity evolution history for single crystal copper at different velocities: (a) U_p = 0.75 km/s; (b) U_p = 1.25 km/s. 不同U_p对应的自由表面速度曲线图　(a) U_p = 0.75 km/s; (b) U_p = 1.25 km/s