从机械结构角度对机械夹持状态下吸收了高能激光束能量的磷酸二氢钾(KDP)晶体内部产生热应力的问题进行了研究。理论分析了KDP晶体吸收激光能量引起的温升,研究了机械夹持状态下KDP晶体内部热应力的生成机理。 采用有限元方法对KDP晶体的温度分布和热应力分布进行了仿真计算,分析了夹持装置结构参数、预紧力、摩擦系数和弹性模量对热应力的影响。结果表明,夹持装置对KDP晶体的机械夹持作用是KDP晶体内部产生热应力的重要因素,热应力的大小与夹持装置的结构参数有关。

From the perspective of mechanical structures, the problem of the thermal stress within the mechanically mounted KDP crystals after the energy absorption from a high-energy laser beam is studied. The temperature rise within KDP crystals induced by the laser energy absorption is theoretically analyzed, and the generation mechanism of the thermal stress within the mechanically mounted KDP crystal is investigated. By the finite element method, the temperature distribution and the thermal stress distribution in KDP crystals are simulated, and the effects of the structural parameters of the mounting set, the preforce, the friction coefficient, and the elastic modulus on the thermal stress are investigated. The results show that the mechanical mounting action provided by the mounting set is a major factor which causes the thermal stress within KDP crystals, and the thermal stress value is associated with the structural parameters of the mounting set.