脉冲CO2激光损伤K9玻璃的实验与仿真

对脉冲CO2激光损伤K9玻璃进行了实验与仿真研究.采用输出脉宽为10μs的脉冲CO2激光器对K9玻璃样品进行激光损伤实验,并且建立了脉冲CO2激光损伤K9玻璃的理论模型,利用有限元法对K9玻璃样品中的温度和应力分布进行数值分析.研究表明,K9玻璃的损伤阈值为6.533 J/cm2;入射激光能量密度越高,样品的损伤程度就越大,并且多脉冲对样品的损伤程度明显大于单脉冲;在激光能量较强的情况下,K9玻璃表面在光斑区域内形成熔融损伤和由压缩应力造成的应力损伤,在光斑区域外围则形成由环向拉伸应力造成的应力损伤,仿真分析结果与实验结果吻合良好.

Simulation and Experimental Research on Damage in K9 Glass due to Pulsed CO2 Laser Radiation

The experiment research on damage in K9 glass induced by pulsed CO2 laser is carried out, which has a pulse width of 10 μs. The theoretical model of K9 glass irradiated by pulsed CO2 laser is developed and a numerical simulation is performed to calculate temperature and stress distributions in K9 glass sample irradiated by pulsed CO2 laser using finite element method. The simulation and experimental results indicate that the damage-threshold of K9 glass irradiated by single pulse is 6.533J/cm2, and the effect of laser irradiation on samples can be affected considerably by the change of laser energy density. The damage mechanism of K9 glass induced by pulsed CO2 laser are melting damage and compress stress damage in irradiated zone, and the damage mechanism of K9 glass induced by pulsed CO2 laser is circular tensile stress damage in the periphery of irradiated zone when the laser energy is high. The model prediction agrees well with the experiment data.