弹体超高速撞击混凝土靶成坑机理和应力波传播规律研究

The hypervelocity weapon platform has developed rapidly in recent years. In order to explore whether the hypervelocity damage unit can effectively damage the underground fortification, it is urgent to study the mechanism of hypervelocity impact on the concrete target. The pit formation mechanism was primarily analyzed based on static parameters such as pit depth measured after a small number of experiments, Due to the lack of experimental parameters which reveal the evolution of the missile-target interface, it is difficult to fully understand the mechanism of complicated hypervelocity impact formation. In the study of stress wave characteristics, there are few effective experimental data, and the study of propagation mechanism is very shallow.In order to reveal the mechanism of hypervelocity (1.5~4km/s) impact on concrete targets and the propagation of stress waves, this project plans to use X-ray radiography to measure the velocity of the missile-target interface and the velocity of the missile tail, and to understand the evolution process of the missile-target interface and the erosive process of projectile, establishing a theoretical model of penetration, revealing the pit formation mechanism; measuring stress along the ballistic axis direction and radial direction in the target under hypervelocity impact conditions using a piezoelectric stress gauge and a two-dimensional electromagnetic particle velocity meter.Analyzing the relationship among the peak value of the stress wave , the impulse and the interface pressure and duration of the missile, we will obtain the attenuation law of the stress wave propagation. The results will provide technical support for the study of the effects of hypervelocity impact damage and the development of weapons platforms.

国外超高速武器平台快速发展，为探索超高速毁伤单元能否对地下工事造成有效毁伤，急需开展超高速撞击混凝土靶的成坑毁伤和应力波毁伤机理研究。在成坑研究方面，仅根据少量实验后测得的成坑深度等静态参数，初步分析了成坑机制，但因为缺乏弹靶界面演化规律等直接反映弹靶作用过程的实验参数，难以深入认识复杂的超高速撞击成坑机理。在应力波特性研究方面，有效实验数据很少，传播机理研究很粗浅。为揭示弹体超高速（1.5~4km/s）撞击混凝土靶成坑机理和应力波传播规律，本项目拟采用X射线照相法测量弹靶界面速度和弹体尾部速度，认识弹靶界面演化过程和弹体侵蚀过程，建立分阶段侵彻的理论模型，揭示成坑机理；采用压电应力计和二维电磁粒子速度计测量撞击条件下靶板中沿弹道轴线方向和径向的应力波特性，分析应力波峰值、冲量与弹靶界面压力、持续时间的关系，获得应力波传播衰减规律。项目成果将为超高速撞击毁伤效应研究和武器平台发展提供支撑。

本项目通过开展系列超高速撞击实验并不断改进测试方案，实现了弹靶界面相互作用和靶内应力波参数的多手段测量，解决了两类实验技术问题，获得了弹靶界面扩展规律和应力波产生传播规律的重要数据，为深入认识超高速撞击机理提供了重要支撑。结合系统的弹靶界面扩展速度和应力波产生传播规律实验数据，通过量纲分析、数值模拟等手段，揭示了超高速撞击混凝土靶的成坑机理，建立了分阶段侵彻的理论模型，获得了应力波传播衰减规律。结果表明：（1）超高速撞击混凝土靶板成坑表现为“弹坑+弹洞”形貌特征，弹坑主要是撞击前期（瞬间开坑阶段和准定常侵彻阶段）巨大的应力波产生的拉应力导致，弹洞则是撞击后期（第三侵彻阶段）弹靶相互作用压碎所致的成坑机理；（2）建立的两种成坑理论模型与实验结果吻合良好，得到的弹靶界面速度、弹体尾部速度、残余弹长、弹靶界面应力等参数与数值模拟吻合度比AT模型更好；（3）可造成有效毁伤的地冲击应力波主要来自于准定常侵彻阶段弹靶间巨大的相互作用，其峰值随传播距离呈指数衰减。项目结果可为超高速撞击毁伤效应研究和武器平台发展提供支撑。