基于损伤力学的蓝宝石激光窗口强度分析及数值仿真研究

A Study on the Strength of Sapphire Laser Windows Based on Damage Mechanics and Numerical Simulation

为了分析蓝宝石激光窗口的强度,基于Hill′48各向异性屈服方程提出了蓝宝石损伤力学模型,开展了数值化方法研究,并编写了计算损伤变量的USDFLD子程序。采用通用有限元分析软件ABAQUS建立了窗口组件有限元分析模型,仿真分析了蓝宝石窗口在高压作用下的应力和损伤变量分布。仿真结果表明,窗口受到高压载荷后,在靠近上边缘处的剪切应力最大,该区域的损伤变量值较大,与试验时窗口破裂位置一致,说明该区域的损伤主要受剪切应力影响。为了提高蓝宝石激光窗口的强度和寿命,对该材料强度理论和相关研究结果分析,讨论了提高蓝宝石窗口强度和寿命的工程化技术措施。

To study the mechanical strength of the laser window made from sapphire,a novel damage model for sapphire based on Hill′48 anisotropic yield function was proposed.The numerical method was used and a corresponding USDFLD subroutine was written for calculating the damage variable.A finite element model was established for the window assembly by ABAQUS,stress and damage variable distributions under high pressure were obtained by simulations.The simulation results show that strong shear stress and high damage variable values exist at the edge of the top surface,which agrees with the window fracture position in experiments,and indicates that the damage in this area is affected by shear stress.In order to improve the strength and life of sapphire laser windows,engineering technology measures were discussed based on the brittle material strength theory and related research analysis.