多脉冲激光辐照增透膜产生热应力的数值模拟

摘要

In this paper,we study and establish the physical model of the multiple pulse laser irradiation Al2O3 anti-re-flection thin film and K9 glass substrate, using the finite element algorithm to solve the corresponding equation of heat conduction and thermal stress, thus having the thermal stress field distribution inside the material. Numerical simulation results show that the ring stress internal material is playing a leading role, and when the temperature cool down, the residual ring thermal stress move along the radial, under the condition of low frequency, the thermal stress damage is the basement first, after then is the thin film. This article research results can provide necessary theory and guidance for laser interaction with film and film anti-laser damage.%研究并建立了多脉冲激光辐照Al2O3增透薄膜及K9玻璃基底的物理模型，采用有限元算法求解相应的热传导方程和热应力方程，得到了材料内部热应力场分布。数值模拟结果表明，材料内部环向力起主导作用，且温度冷却时，残余环向热应力沿径向移动，在低频情况下，先发生热应力损伤的是基底，后发生热应力损伤的是薄膜。研究成果可为激光与薄膜相互作用机理以及薄膜的抗激光损伤提供一定的理论依据和指导。