为探讨中厚背水金属靶板抗高速钝头弹垂直侵彻机制，根据不同的受力状态及耗能机制，结合中厚背水靶板抗高速侵彻特点，将高速钝头弹垂直侵彻中厚背水金属靶板的过程分为压缩镦粗、剪切压缩和剪切扰动3个阶段.基于3阶段侵彻机制，建立了钝头弹高速侵彻中厚背水金属靶板的瞬时余速计算模型.采用该模型计算了质量为3.3g的立方体破片弹丸侵彻厚度为5mm背水钢板的瞬时余速，理论计算值与实验结果及相应的模拟计算结果均吻合较好.由于计算模型考虑了靶后水介质的动支撑作用和动能耗散等效应，对高速钝头弹侵彻中厚背水金属靶板的瞬时余速能进行更合理的预测，具有一定的理论价值和工程应用价值.
To explore the mechanism of moderately thick water-backed metal plates penetrated by high-velocity blunt-nosed projectiles, the whole process of high-velocity blunt-nosed projectiles perpendicularly penetrating moderately thick water-backed metal plates was divided into three consecutive phases, i.e., compression and mushrooming phase, shearing and compression phase and shearing and intruding phase, according to different mechanical states and energy-dissipative mechanisms during penetrating process together with the high-velocity penetration-resistant characteristic of moderately thick water-backed metal plates. Based on the 3-phase penetration mechanism, an analytical model was established to calculate instantaneous residual velocities of the blunt-nosed projectiles perforating moderately thick water-backed metal plates. By adopting the model, the instantaneous residual velocities of cubic projectiles with 3.3g penetrating 5mm-thick water-backed steel plates were computed. Good agreements were obtained between the theoretical values and experimental results as well as corresponding numerical results. Due to the consideration for several phenomena, such as the dynamic supporting action and kinetic energy dissipation effort of the water medium behind the target, the 3-phase model can be employed to more reasonably predict the instantaneous residual velocities of the blunt-nosed projectiles perforating moderately thick water-backed metal plates, and therefore, has theoretical and engineering application value.
［1］MCMILLEN J H. Shock wave pressures in water produced by impact of small spheres［J］. Physical Review, 1945, 68(9/10): 198-209.
［2］TOWNSEND D, PARK N, DEVALL P M. Failure of fluid dilled structures due to high velocity fragment impact［J］. International Journal of Impact Engineering, 2003, 29(1): 723-733.
［3］DISIMILE P J, SWANSON L A, TOY N. The hydrodynamic ram pressure generated by spherical projectiles［J］. International Journal of Impact Engineering, 2009, 36(6): 821-829.
［4］VARAS D, LOPEZ-PUENTE J, ZAERA R. Experimental analysis of fluid-filled aluminium tubes subjected to high-velocity impact［J］. International Journal of Impact Engineering, 2009, 36(1): 81-91.
［5］DELETOMBE E, FABIS J, DUPAS J, et al. Experimental analysis of 7.62 mm hydrodynamic ram in containers［J］. Journal of Fluids and Structures, 2013, 37(2): 1-21.
［6］徐双喜, 吴卫国, 李晓彬, 等. 舰船舷侧防护液舱舱壁对爆炸破片的防御作用［J］. 爆炸与冲击, 2010, 30(4): 395-400.
XU Shuangxi, WU Weiguo, LI Xiaobin, et al. Protective effect of guarding fluid cabin bulkhead under attacking by explosion fragments［J］. Explosion and Shock Waves, 2010, 30(4): 395-400.
［7］王晓强, 朱锡. 高速钝头弹侵彻中厚金属靶板的机理研究［J］. 工程力学, 2010, 27(12): 213-218.
WANG Xiaoqiang, ZHU Xi. Study on high-velocity blunt-nosed projectiles penetrating moderate thickness metallic targets［J］. Engineering Mechanics, 2010, 27(12): 213-218.
［8］马晓青, 韩峰. 高速碰撞动力学［M］. 北京: 国防工业出版社, 1998.
［9］张晓晴, 杨桂通, 黄小清. 柱形平头弹体墩粗变形的理论分析［J］. 华南理工大学学报(自然科学版), 2005, 33(1): 32-36.
ZHANG Xiaoqing, YANG Guitong, HUANG Xiaoqing. Theoretical analysis of the mushrooming deformation of flattened cylindrical projectile［J］. Journal of South China University of Technology (Natural Science Edition), 2005, 33(1): 32-36.
［10］LIANG C C, YANG M F, WU P W, et al. Resistant performance of perforation of multi-layered targets using an estimation procedure with marine application［J］. Ocean Engineering, 2005, 32(3/4): 441-468.
［11］王礼立. 应力波基础［M］. 北京: 国防工业出版社, 2010.
［12］胡昌明, 贺红亮, 胡时胜. 45号钢的动态力学性能研究［J］. 爆炸与冲击, 2003, 23(2): 188-192.
HU Changming, HE Hongliang, HU Shisheng. A study on dynamic mechanical behavior of 45 steel［J］. Explosion and Shock Waves, 2003, 23(2): 188-192.
［13］梅志远, 朱锡, 张立军. 高速破片穿透船用钢靶剩余特性研究［J］. 工程力学, 2005, 22(4): 235-240.
MEI Zhiyuan, ZHU Xi, ZHANG Lijun. The residual characteristic of high-velocity fragments after perforation of ship hull［J］. Engineering Mechanics, 2005, 22(4): 235-240.
