纳秒脉宽Nd…YAG激光冲击强化激光器的研制及分析  

Develop and Analysis of Nanosecond Pulse Width Nd…YAG Laser for Laser Peening

作　　者：乔红超[1] 赵吉宾[1] 陆莹[1,2] 

机构地区：[1]中国科学院沈阳自动化研究所,辽宁沈阳110016 [2]哈尔滨工业大学,黑龙江哈尔滨150001

出　　处：《中国激光》2013年第8期1-7,共7页Chinese Journal of Lasers

基　　金：国家863计划(2012AA041310)

摘　　要：针对近年来发展的提高工件疲劳寿命的激光冲击强化技术,采用一级谐振级8级放大级的系统结构和模块化设计方法,研制出了激光冲击强化用大能量、短脉宽、高频率的Nd···YAG脉冲固体激光器,分析了激光器的设计方案、激光光路布置特点,并对其技术指标进行了测试。在预热20min后、环境温度变化小于2℃的情况下,单脉冲最大输出能量达25J,能量不稳定度小于3%,脉宽在1620ns范围内连续可调,脉宽不稳定度小于±1ns,光束发散角不超过2.5mrad,重复频率达5Hz。为进一步验证激光器的性能,对TC4钛合金进行了激光冲击强化试验,大幅度提高了TC4钛合金试件表面的残余压应力,测试和试验结果均表明,激光器的各项性能良好。For the laser peening technology which is a recently-developed surface treatment method designed to improve the fatigue life of mechanical parts, using a oscillation eight-stage amplified system structure and the modular design method, high-energy, short-pulse and high-frequency Nd： YAG solid-state lasers are developed. Design scheme of the laser and the characteristics of laser beam transmission are presented and discussed. At ambient temperature which changes less than 2 ~C and after 20 rain of warm-up, the technical parameters such as the maximum single pulse energy of 25 J, energy instability less than 3%, pulse width which can be continuously adjustable between 16 ns and 20 ns, pulse width instability less than -k-1 ns, beam divergence less than 2.5 mrad, and the maximum single frequency of 5 Hz are achieved. To further verify the performance of the lasers, a TC4 titanium alloy work-piece is tested with the Nd： YAG lasers. The tested results show that the compressive residual stress is greatly improved and the performance of the lasers is excellent.

关 键 词：激光技术 激光冲击强化 纳秒脉宽 脉冲能量 大能量激光 

分 类 号：TN248.1[电子电信—物理电子学]