中国科学院沈阳自动化研究所机构知识库

激光冲击强化是一种先进表面技术,其利用激光诱导形成的等离子冲击波对金属材料进行强化,因具有强化效果更佳、可操控性更强和适用性更好等技术优势,得到了越来越广泛的应用与研究,对提高部件的疲劳性能和延长材料使用寿命具有重要作用。简要介绍了激光冲击强化技术的发展概况,分别从激光工艺参数、约束层与吸收保护层、冲击角度等影响参数进行了重点分析与总结。激光工艺参数是影响强化效果的最重要因素,选取最佳的激光功率密度、最优的光斑搭接率、适当的冲击次数以及合适的脉冲宽度可以明显提高强化效果。针对不同的材料形态,应选取合适的约束层和吸收保护层,提高激光透光率的同时防止材料表面烧蚀。此外还需考虑激光冲击强化的冲击角度,选择合适的冲击角度,能够对复杂的结构进行强化。综合考虑激光冲击强化的影响参数,可为得到最佳激光冲击强化效果提供重要的理论参考。

Laser shock processing is an advanced surface technology to strengthen metal materials by the laser-induced plasma shock wave, thus getting more and more applications and researches, and playing an important role in improving fatigue properties of components and extending service life of materials due to its technical advantages, such as better strengthening effect, stronger controllability and better applicability, etc. The development of laser shock processing was briefly introduced, and the laser parameters, confinement layer, absorbing protective layer, laser shocked angle and other influencing parameters were emphatically analyzed and summarized, respectively. The laser parameters are the most important factors to determine the strengthening effect and the optimal laser power density, optimum spot overlap ratio, suitable laser shocked times and appropriate laser pulse width can be selected to significantly improve the strengthening effect. For the different material forms, the appropriate confinement layer and the absorbing protective layer should be selected to improve the laser transmittance and prevent the laser ablation of the material in near surface. In addition, the laser shocked angle should be considered, and the appropriate suitable laser shocked angle can realize the laser shock processing for complex structure. Therefore, the influence parameters of laser shock processing should be considered comprehensively, to provide a theoretical basis for obtaining the best strengthening effect of laser shock processing.