以激光介质的第一主应力为评判标准, 依据Griffith微裂纹理论作为断裂临界应力, 基于已报道的断裂实验数据和3维、瞬态的有限元计算, 建立了预测一定泵浦参数下钕玻璃断裂可能性的Weibull统计模型, 同时分析了影响介质泵浦极限的其它因素。结果表明：材料的抛光工艺决定了介质的断裂应力;对于短脉冲大能量方式工作的钕玻璃介质, 基于美国20世纪90年代的抛光水平, 1 Hz以下低重频时应优先考虑18 kW·cm-2的泵浦饱和极限, 10 Hz以上高重频时应优先考虑介质的断裂极限。

Based on published fracture experiments and 3D transient finite-element analyses, and taking the first principal stress as the criterion and the Griffith crack theory to determine the critical fracture stress, a Weibull statistical model is established to predict the fracture possibility of Nd:glass with certain pump parameters. Other issues which limit the pump power are also presented. The results show that the fracture limit of laser medium depends on the optical polishing technology. For a short pulse and high energy Nd:glass laser, taking America’s polishing technology in the 1990s as reference, the pump saturation limits the pump power to 18 kW/cm2 when the repetition rate is lower than 1 Hz, while the thermal fracture limits the pump power when the repetition rate is higher than 10 Hz.