This paper presents a systematic computational study to investigate the effects of crystal orientation, strain rate (impact velocity), and size (thickness) on plasticity and damage behavior of copper single crystals during the penetration process at the atomistic scale. For the penetration analysis, copper single crystals with different crystal orientations and thicknesses were impacted and penetrated by a cylindrical nickel penetrator at different initial velocities. Modified embedded atom method potentials were used to develop atomistic models, and over 250 molecular dynamics simulations were performed to fully reveal the effects of influence parameters on plasticity and damage behavior of the copper single crystals. The results show that the copper single crystal with an octal slip orientation exhibits the greatest strength and penetration resistance, while the copper crystal with the single slip orientation exhibits the lowest strength and resistance. The results further show that the strength and penetration resistance of the target increase as the thickness of the copper single crystals increases. Furthermore, as the impact velocity increases, damage and fragmentation increase. Conclusions drawn from this computational study are consistent with macroscale plasticity theories of metals and reaffirm the conclusions drawn by other researchers in previous experimental studies.

中文翻译：

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晶体取向、尺寸尺度和应变速率对受镍穿透器在极高应变速率下冲击的单晶铜穿透机制影响的分子动力学研究

本文提出了一项系统的计算研究，以研究晶体取向、应变速率（冲击速度）和尺寸（厚度）对原子尺度渗透过程中铜单晶塑性和损伤行为的影响。对于穿透分析，具有不同晶体取向和厚度的铜单晶被圆柱形镍穿透器以不同的初始速度撞击和穿透。使用改进的嵌入原子法势开发原子模型，并进行了超过 250 次分子动力学模拟，以充分揭示影响参数对铜单晶塑性和损伤行为的影响。结果表明，八方滑移取向的铜单晶强度和抗穿透性最强，而单滑移取向的铜单晶强度和抗渗透性最低。结果进一步表明，随着铜单晶厚度的增加，靶材的强度和抗穿透性增加。此外，随着撞击速度的增加，损坏和破碎也会增加。这项计算研究得出的结论与金属的宏观塑性理论一致，并重申了其他研究人员在以前的实验研究中得出的结论。结果进一步表明，随着铜单晶厚度的增加，靶材的强度和抗穿透性增加。此外，随着撞击速度的增加，损坏和破碎也会增加。这项计算研究得出的结论与金属的宏观塑性理论一致，并重申了其他研究人员在以前的实验研究中得出的结论。结果进一步表明，随着铜单晶厚度的增加，靶材的强度和抗穿透性增加。此外，随着撞击速度的增加，损坏和破碎也会增加。这项计算研究得出的结论与金属的宏观塑性理论一致，并重申了其他研究人员在以前的实验研究中得出的结论。