对00Cr12合金耐热钢选用合适的参数进行激光冲击强化(LSP),并对其疲劳极限进行了快速测定。探讨和分析了激光冲击前后00Cr12合金表层残余应力与微观组织的变化对其疲劳寿命的影响。试验结果表明,激光冲击诱使材料表面产生了弹塑性形变,从而在表层产生了残余压应力与高密度位错,有效地提高了疲劳寿命。00Cr12合金试样经激光冲击强化后,寿命是未处理的1.6倍。所选用的Locati阶梯式疲劳试验方法与传统的升降法所得到的结果相比,相对误差较小,可快速地为机械的疲劳设计提供可靠的数据。
The 00Cr12 alloy heat-resistant steel was strengthened by laser shock processing(LSP) with appropriate parameters,and its fatigue limitation was measured rapidly.The effects of residual stress and microstructure change of the surface layer of 00Cr12 alloy on its fatigue life were discussed and analyzed before and after LSP.The results showed that elastic-plastic deformation was induced by laser impulse on the material surface,which resulted in residual compressive stress and dislocations of high density in the material surface,so the fatigue life of 00Cr12 alloy was effectively improved by LSP.After LSP,the fatigue life of 00Cr12 alloy was 1.6 times as much as the sample without LSP.Compared with the traditional rising and falling methods,the relative error of the results obtained by Locati multistep method was small.This method could provide reliable data for fatigue design of machines.