激光冲击诱导弹簧钢丝残余应力状态分析

Analysis of residual stress state of spring steel wire induced by laser shock processing

利用高功率Nd:YAG激光对不同工艺处理的SWOSC-V弹簧钢丝进行单点冲击处理,用X射线应力分析仪测量弹簧内外侧、侧表面的残余应力并计算出残余主应力,建立了激光冲击SWOSC-V弹簧钢丝表面残余应力的产生模型,并利用该模型分析了弹簧钢丝表面残余应力产生的原因。结果表明:弹簧钢丝在经激光冲击处理的表面强化区产生残余压应力,钢丝退火后直接激光冲击处理与经喷丸强化的钢丝激光冲击处理的表面残余应力变化不同,喷丸强化所引起的材料硬化是激光冲击处理弹簧钢丝残余应力变化不同的原因。

The SWOSC V spring steel wires manufactured by different treatment processes were treated by laser shock pro- cessing （LSP） with high power Nd：YAG laser. Residual stresses on inner surface, outer surface and lateral surface were meas- ured by X-ray diffraction （XRD） and principal stresses were calculated. The generation model of laser shock waves in springs was established, and reasons of residual stress generation on spring surface were explained. Residual compressive stresses on each sur- face of springs were obtained. The changes of residual stress are different between LSP on the annealed spring and the shot blast- ed spring, and the material hardening by shot peening（SP） is the reason for the different changes of residual stress by LSP.