高功率激光钕玻璃椭圆片硬包边残余应力研究  

Investigation on Residual Stress in Monolithic Edge-Cladding of Elliptical Nd-Doped Phosphate Laser Glass for High-Peak Power Solid-State Laser

作　　者：陈辉宇[1,2] 钱敏 唐景平[1] 程继萌 王欣[1] 胡俊江[1] 孟涛[1] 沈玉晶[1] 陈树彬[1] 胡丽丽[1] 陈伟[1] Chen Huiyu;Qian Min;Tang Jingping;Cheng Jimeng;Wan Xin;Hu Junjiang;Meng Tao;Shen Yujing;Chen Shubin;Hu Lili;Chen Wei(Key Laboratory of Materials for High Power Laser,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800;University of Chinese Academy of Sciences,Beijing 100049)

机构地区：[1]中国科学院上海光学精密机械研究所强激光材料重点实验室,上海201800 [2]中国科学院大学,北京100049

出　　处：《中国激光》2021年第9期70-83,共14页Chinese Journal of Lasers

基　　金：国家惯性约束聚变领域资助项目(G-GFZX02050102021)。

摘　　要：硬包边是激光钕玻璃减少放大自发辐射和抑制寄生振荡的包边技术之一,残余应力是硬包边的一个重要参数。详细描述了激光钕玻璃硬包边过程中残余应力的来源,并利用有限元分析软件COMSOL Multiphysics,对硬包边浇注熔接过程中不同膨胀系数匹配条件和不同包边玻璃浇注温度下的残余应力分布进行了数值模拟。结果显示,激光钕玻璃和包边玻璃的膨胀系数差异愈小,产生的残余应力愈小;包边玻璃浇注温度愈高,则产生的残余应力愈大。硬包边实验结果表明:包边玻璃的膨胀系数和激光钕玻璃的膨胀系数愈相近,则残余应力就愈小,当包边温度在700~1200℃范围内时,残余应力随着包边温度的增加而增大。模拟结果与实验结果吻合,所以在硬包边的浇注熔接过程中,为了使残余应力最小,最佳策略是激光钕玻璃的膨胀系数和包边玻璃的膨胀系数尽量接近甚至相等,且包边温度尽量低。Objective Inertial Confinement Fusion(ICF)is one of the technical approaches to realize controllable nuclear energies.The key to ICF is the high-peak power solid-state laser system.A large-sized,Nd-doped phosphate laser glass disk is the core gain material of the high-peak power solid-state laser system.In the gain media,the amplified spontaneous emission(ASE)and parasitic oscillation(PO)are generated,which can affect the energy storage efficiency and laser output capability of the high-peak power solid-state laser system.Now,the main method to absorb ASE and suppress PO is to clad the Cu^(2+)-doped glass at the peripheral edge of the Nd-doped phosphate laser glass.The edge-cladded Cu^(2+)-doped glass can absorb the reflected or scattered light at 1μm and suppress the onset of parasitic oscillation.At first,the sealing edge-cladding method was applied to the elliptical slab of N21 Nd-doped phosphate laser glass and the N21 rectangular Nd-doped phosphate laser glass,immersed in the organic cooling medium in the high-power laser system.The sealing edge-cladding process involves first mixing a low melting temperature glass powder with a dispersant to form a slurry,then coating the slurry on the edge of the Nd-doped phosphate laser glass,and finally heat-treating the coated glass at below a temperature at which the Nd-doped phosphate laser glass is softened and deformed to bond the low melting temperature glass to the edge of the Nd-doped phosphate laser glass.However,this cladding method can create lots of defects such as bubbles,pits,and carbide at the cladding interface.These defects can increase the residual reflection(0.1×10^(-2)-25×10^(-2)),which can lead to a considerable increase in ASE and PO.With a rapid advancement in the laser technologies,the Nd-doped phosphate laser glass with better performance is obtained,such as the types of N31 and N41.They have relatively low soften temperatures.Also,the temperature for heat-treating coated glass is much lower than that of N21,which can result in more defects at

关 键 词：材料 激光钕玻璃 硬包边 有限元分析 激光元件 应力双折射率 残余应力 

分 类 号：TQ171.73[化学工程—玻璃工业] O436.3[化学工程—硅酸盐工业]