灌封材料对侵彻过载下弹载器件的防护分析

为研究在灌封材料缓冲保护下弹载器件对冲击载荷的动态响应，利用LS-DYNA用户材料自定义程序UMAT二次开发平台，编写朱-王-唐（ZWT）非线性黏弹性本构模型的材料子程序，并将ZWT模型应用于弹体内部灌封材料的动态仿真。通过调整ZWT模型的非线性弹性模量、低应变率Maxwell单元的弹性常数、高应变率Maxwell单元的弹性常数、高应变率Maxwell单元的松弛时间和材料密度，得出不同参数对应下，弹体内部电子器件不同的动力学响应，并分析灌封材料各参数变化对于弹体内部电子器件响应造成的影响。研究结果表明：当非线性弹性模量、低应变率Maxwell单元的弹性常数、高应变率Maxwell单元的松弛时间和材料密度的数值降低时，灌封材料的减振和防护效果更佳。根据仿真结果提出了针对不同工程需求的材料优化方案。

Dynamic Analysis of Projectile-borne Electronic Devices under Impact Loading

The dynamic responses of projectile-borne electronic devices which are protected by encapsulating material under impact loading are studied through numerical simulation.A LS-DYNA user defined material subroutine is established according to the ZWT nonlinear viscoelastic model which is used for simulating the dynamic response of the encapsulating material in the projectile.The simulations of projectile penetration were performed by adjusting the controllable parameters of ZWT model,such as nonlinear elasticity modulus,low strain rate Maxwell elastic constant,high strain rate Maxwell elastic constant,high strain rate Maxwell relaxation time and material density.Thus the dynamic responses of projectileborne electronic devices could be obtained from the numerical results.The research results show that the shock absorption and protection effects of the encapsulating materials are better when the values of nonlinear elasticity modulus,low strain rate Maxwell elastic constant,high strain rate Maxwell relaxation time and material density are decreased.