孔洞增长层裂模型的改进及其在模拟不同加载波形层裂实验结果方面的应用  

Improvement of void growth model and its application in simulating spallation experiments under different impact loading wave forms

作　　者：张凤国[1] 王裴[1] 王言金[1] 胡建波[2] ZHANG Fengguo;WANG Pei;WANG Yanjin;HU Jianbo(Institute of Applied Physics and Computational Mathematics,Beijing 100094,China;National Key Laboratory of Shock Wave and Detonation Physics,Institute of Fluid Physics,China Academy of Engineering Physics,Mianyang 621999,Sichuan,China)

机构地区：[1]北京应用物理与计算数学研究所,北京100094 [2]中国工程物理研究院流体物理研究所冲击波物理与爆轰物理全国重点实验室,四川绵阳621999

出　　处：《爆炸与冲击》2024年第5期48-53,共6页Explosion and Shock Waves

基　　金：国家自然科学基金(12271054)。

摘　　要：冲击波在靶板自由面反射导致靶板材料内部产生动态拉伸层裂损伤是材料的典型损伤破坏形式之一,材料的初始微结构、冲击加载的强度和应变率、温度等因素直接影响材料内部的损伤演化过程。靶板自由面速度曲线变化间接反映材料内部损伤的演化过程,在层裂损伤物理模型研究方面,目前采用适宜的层裂损伤模型较好地模拟不同冲击加载波形下靶板自由面速度曲线的相关文献很少,主要借助实验手段探讨加载波形与自由面速度曲线变化以及层裂损伤演化过程之间的关联。对于孔洞增长层裂损伤模型,通过解析加载应变率与层裂强度以及损伤模型初始损伤参数之间的相互关系,给出了模型初始损伤参数的计算方法,有效地将损伤模型初始损伤参数与加载应变率关联在一起。该计算方法不仅可以较好地模拟方波、三角波以及泰勒波冲击加载铝材料层裂实验的自由面速度曲线,同时,计算得到的层裂强度和层裂片厚度也与实验结果符合。此外,还进一步分析了靶板内部不同位置的初始损伤、层裂强度的分布与应变率之间的关联,以及其对自由面速度曲线的影响。The dynamic tensile spallation damage caused by shock wave reflection on the free surface of target is one of the typical damage modes of materials.The initial microstructure of materials,the magnitude and strain rate of impact loading,temperature and other factors directly affect the spallation damage evolution process in materials.The change of free surface velocity c at the target indirectly reflects the evolution process of spall damage in materials.Regarding the study of physical model of spallation damage,only limited literatures are available on using suitable spallation damage model to simulate the free surface velocity profile of target under different impact loading waveforms.The relationship between loading waveforms and free surface velocity profile as well as the evolution process of spallation damage were mainly investigated by means of experiments.Considering that both the shear viscosity coefficient and the hardening coefficient are the basic parameters of the material,the calculation of the initial damage parameters of the damage model is now obtained by analyzing the relationship between the spall strength,the loading strain rate and the initial damage parameter of the damage model.The initial damage parameter of the damage model is effectively associated with the loading strain rate,and the programmed automatic calculation of the initial damage parameter under different loading strain rate is realized.On this basis,not only the free surface velocity profiles of spallation tests of aluminum materials loaded by square wave, triangular wave and Taylor wave can be well simulated, the calculated spall strengths and spall plate thicknesses are also consistent with the tests results. In addition, the relationship between the distribution of initial damage, spall strength and loading strain rate at different positions in the target is further anayzed. Consequently, compared with the existing damage model, the new method not only further improves the existing damage model, but also improves the validity

关 键 词：冲击加载波形 层裂损伤 自由面速度 数值分析 

分 类 号：O346.1[理学—固体力学]