激光冲击强化激光器的研制

摘要

针对近年来发展的激光冲击强化技术,采用1级谐振8级放大的系统结构和模块化设计方法,研制出了激光冲击强化用短脉宽、大能量的Nd:YAG脉冲激光器,并对激光器技术指标进行了测试分析.在预热20 min后、环境温度变化小于2℃的情况下,单脉冲最大输出能量高达25 J,能量不稳定度小于3％,脉宽16～20 ns可调,脉宽不稳定度小于±1 ns,光束发散角小于等于2.5 mrad,重复频率达5 Hz.对TC4钛合金进行激光冲击强化实验,大幅度提高了TC4钛合金试件表面的残余压应力.结果表明,研制的激光器各项性能良好.%The laser peening technology is a recently-developed surface treatment method.Using an oscillation eight-stage amplified system structure and the modular design method,a short pulse and high power Nd:YAG laser system for laser peening has been developed and tested.At ambient temperature which changes less than 2 ℃,after 20 min of warm-up,the maximum pulse energy is 25 J,the energy instability is less than 3％,the pulse width is adjustable between 16 ns and 20 ns,the pulse width instability is less than ± 1 ns,the beam divergence is less than 2.5 mrad,and the maximum frequency is 5 Hz.A TC4 titanium alloy work-piece is processed with the laser system,the compressive residual stress is greatly improved.The results show that the performance of the laser system is very excellent.