工程陶瓷表面抗激光损伤能力研究

Laser Damage Resistance of Engineering Ceramics

实验研究了纳秒激光辐照下不同材料的工程陶瓷表面的抗激光损伤能力,并与不锈钢、铝合金等金属材料进行了对比.结果表明,不同材料的工程陶瓷表面抗激光损伤特性不同;氧化铝陶瓷的损伤阈值最高,氮化硅陶瓷的损伤阈值较低.与金属材料相比较,工程陶瓷表面损伤阈值比不锈钢和铝合金高.由于材料的熔点和热传导率等热力学特性不同,不同的陶瓷材料具有不同的损伤阈值和损伤形貌.理论分析了不同材料抗激光损伤阈值的差异;陶瓷材料的吸收系数远远小于金属材料,吸收系数通过影响能量沉积区域和有效热扩散速率影响材料温度的演化过程,最终影响着材料的激光损伤阈值和损伤特性.实验结果为高功率激光装置中对抗激光损伤能力要求较高的机械支撑材料的选择提供了指导.

Laser damage resistance of different kinds of engineering ceramics under nanosecond laser irradiation were studied and compared with those of stainless steel and aluminum alloy.The results show that the laser damage characteristics of different materials are different.The damage threshold of alumina ceramics is the highest,while the damage threshold of silicon nitride ceramics is lowest.Compared with metal materials,the damage thresholds of engineering ceramics are higher than those of stainless steel and aluminum alloy.Due to the difference of the melting point and thermal conductivity,different kinds of ceramic material have different damage morphologies.The difference of laser damage threshold of different materials was analyzed theoretically;the absorption coefficient of ceramic materials is less than metals.The absorption coefficient have an effect on the energy deposition area and heat diffusion rate influencing the evolution process of the temperature,which ultimately affect the laser damage threshold value and damage characteristics of materials.The experimental results provide guidance for the selection of mechanical support materials for high power laser devices.