尖头弹丸撞击下金属靶板弹道极限的两种工程模型

研究了圆锥形头和卵形头刚性弹垂直撞击塑性金属靶板扩孔冲塞型和延性扩孔型穿孔模式,考虑靶板背面自由边界的影响,提出两种两阶段工程分析模型,得到最小穿透能量的解析解。由球形空腔膨胀理论和两阶段总耗能最小确定第一阶段的侵彻深度,由功能原理和圆柱形空腔膨胀理论计算第一阶段侵彻扩孔耗能,延性扩孔型第二阶段耗能近似按Taylor扩孔理论计算,扩孔冲塞型第二阶段耗能考虑了加速塞块和剪断塞块所损耗的能量。与铝合金和装甲钢靶板弹道试验数据比较表明,本文两阶段模型的计算结果与试验结果吻合较好。

Two Analytical Models for Ballistic Limit of Metallic Targets Struck by Rigid Sarp-Nosed Projectiles

Two models are developed for ballistic impact of moderately thick metallic plates struck by rigid projectiles with conical or ogival noses. The initial stage is characterized by ductile hole enlargement and radial plastic flow of the plate materials. The plug formation is considered in the second stage of the two stage plugging model. The formulas for energy dissipated by the ductile hole enlargement are derived from cylindrical cavity expansion approximation. The penetration depth X 1 during the first stage is determined by minimizing the total energy dissipated during the two stages for the two stage ductile hole enlargement model, or by using spherical cavity expansion approximation for the two stage ductile hole enlargement model, analytical formulas for critical impact energy and ballistic limits are obtained.The accuracy of these models is discussed by comparing their predictions with previously published ballistic test results and the other analytical formulas.