CAJ | 학술논문

为评价激光冲击强化效果，通常采用X射线衍射法（XRD）测定工件的残余应力分布。由于X射线穿透深度一般在微米数量级，为获得工件深度方向上的残余应力分布规律，常采用电解抛光的方法逐层剥离工件表面材料。逐层剥离过程改变了工件表面的边界条件，使得残余应力分布发生了改变，导致XRD实验测得的残余应力与未剥离前不同。本文采用有限元数值模拟方法研究了剥离过程对激光诱导残余应力场分布的影响。结果表明：在残余压应力区域，剥离材料后内部的残余压应力较剥离前增大，残余压应力增加程度随着剥离深度的增大而增加；剥离表面较浅一层材料时，整体残余应力场的分布变化较小，且有利于消除激光冲击强化产生的“残余应力洞”。该研究对基于XRD实验测定的残余应力修正具有一定的指导意义。
위평개격광충격강화효과，통상채용X사선연사법（XRD）측정공건적잔여응력분포。유우X사선천투심도일반재미미수량급，위획득공건심도방향상적잔여응력분포규률，상채용전해포광적방법축층박리공건표면재료。축층박리과정개변료공건표면적변계조건，사득잔여응력분포발생료개변，도치XRD실험측득적잔여응력여미박리전불동。본문채용유한원수치모의방법연구료박리과정대격광유도잔여응력장분포적영향。결과표명：재잔여압응력구역，박리재료후내부적잔여압응력교박리전증대，잔여압응력증가정도수착박리심도적증대이증가；박리표면교천일층재료시，정체잔여응력장적분포변화교소，차유리우소제격광충격강화산생적“잔여응력동”。해연구대기우XRD실험측정적잔여응력수정구유일정적지도의의。
In order to evaluate the effect of laser shock peening,the residual stress distribution of workpieces is usuallymeasured by the X -ray diffraction method(XRD).Since the penetration depth of X -ray is in the range of microme-ter,in order to obtain the distribution of residual stress in depth,the surface materials are often stripped layer by layerby the electrolytic polishing method.Layer -stripping process changes the boundary conditions of workpiece surface,so the distribution of residual stress is changed.The residual stress value obtained by the XRD experiment is not thesame as that without layer -stripping.In this paper,finite element numerical simulation method is adopted to study theeffect of layer -stripping process on the distribution of residual stress induced by laser.The result shows that:in thecompressive residual stress region,the compressive residual stress value after stripping is greater than that withoutstripping,and compressive residual stress of the material increases with the stripping depth increases;there will be lit-tle influence on the residual stress distribution if the stripped layer is shallow.It will be conducive to the elimination ofthe "residual stress hole"by laser shock peening.This research has theoretical significance to the correction of residu-al stress based on the XRD experiment.