激光喷丸改善零件疲劳性能的研究现状及展望

Review and expect of laser peening for improving fatigue performance of parts

激光喷丸能够提高零件表面硬度、增加压应力幅值及深度,延缓裂纹的萌生和扩展,已成为一种有效改善零件疲劳性能的方法。主要影响激光喷丸零件疲劳性能的因素包括激光能量、喷丸温度及重复喷丸的次数。介绍了激光能量与零件疲劳性能的关系,包括激光能量的传播、转化以及诱导产生的冲击波与零件的相互作用机理。分析了不同处理温度条件下激光喷丸零件的强化机制,并说明了激光喷丸温度与零件服役范围的关系。总结了重复喷丸次数对零件表面强化层的影响。最后从激光喷丸强化机理方面讨论了激光喷丸在改善零件疲劳性能方面的优势,并对进一步的研究方向进行了展望。

Laser peening can improve the surface hardness,compressive stress amplitude and depth,delay the initiation and propagation of cracks. It has become an effective way to improve fatigue performance of the parts. The influencing factors of fatigue performance of laser peening parts include laser energy,treatment temperature and the number of repeated laser peening. The relationship of the laser energy and fatigue performances of the parts is introduced,including shock waves induced by laser energy transmission,transformation and interaction mechanism with material. The strengthening mechanism of laser peening parts under the different processing temperature is analyzed,and the relationship between the treatment temperature and parts service environment is explained. The effect of the number of repeated laser peening on the properties of surface layer is summarized. The advantage of laser peening to improving the fatigue strength of the parts are summarized by the strengthening mechanisms of laser peening,and the futher reseach directions are suggested.