刚性尖头弹垂直撞击金属厚靶板极限速度分析

研究了刚性尖头弹垂直撞击金属厚靶板扩孔冲塞型和延性扩孔型穿孔模式，提出分析最小穿透能量的两阶段工程模型．应用功能原理和圆柱形空腔膨胀理论得到第一阶段侵彻扩孔耗能．考虑靶板背面自由边界的影响，应用Taylor扩孔理论计算延性扩孔型穿孔第二阶段耗能；考虑加速塞块和剪断塞块所损耗的能量，由动量和能量原理导出扩孔冲塞型穿孔第二阶段剪切冲塞耗能．由两阶段总的耗能最小确定第一阶段的侵彻深度，从而得到最小穿透能量的解析解．与铝合金和装甲钢靶板弹道试验数据比较表明，该文两阶段模型的计算结果与试验结果吻合较好。

ANALYSIS ON BALLISTIC LIMIT OF METALLIC TARGETS STRUCK BY RIGID SARP-NOSED PROJECTILES

Two models are developed for ballistic impact of thick metallic plates struck by non-deformable projectiles with conical or ogival noses by considering two interconnected perforation stages. The initial stage is characterized by ductile hole enlargement and radial plastic flow of the plate materials. The influence of the rear face of the plates on ductile hole enlargement is involved in the second stage. The formation of the plug is considered in the second stage of the two-stage plugging model. Formulas for energy dissipated by the plate during ductile hole enlargement are derived from the cylindrical cavity expansion approximation. The penetration depth X 1 during the first stage is determined by minimizing the total energy dissipated by the plate during the two stages.Analytical formulas for critical impact energy and ballistic limits are obtained.The accuracy of the models is discussed through comparing their predictions with previously published ballistic test results and other analytical formulas.