Abstract Threshold modes of multiscale dynamic deformation were identified for 1561 aluminum alloy by conducting two series of impact tests in the velocity range of 250–750 m/s: under uniaxial deformation and with high-speed penetration of elongated impactors. It was found that the scale of deformation changes at the same strain rate in the spall fracture zone under uniaxial deformation and on the lateral cavity face during impactor penetration. The scale changes due to resonant interaction between oscillations of plastic flow and structural elements of the deformed material. A constitutive equation was derived for multiscale dynamic deformation, and a transport equation was obtained to describe energy exchange between the scale levels. The transition of dynamic deformation to a larger scale level was shown to reduce the resistance to the high-speed penetration of elongated impactors.

中文翻译：

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冲击载荷下的多尺度细观结构形成

摘要 通过在 250-750 m/s 的速度范围内进行两个系列的冲击试验，确定了 1561 铝合金的多尺度动态变形的阈值模式：单轴变形和细长冲击器的高速穿透。发现在单轴变形下的剥落断裂区和冲击器穿透过程中的横向空腔面上，变形尺度在相同的应变速率下发生变化。由于塑性流动的振荡与变形材料的结构元素之间的共振相互作用，尺度发生变化。推导了多尺度动态变形的本构方程，并获得了描述尺度水平之间能量交换的输运方程。