光电工程, 2017, 44 (6): 569, 网络出版: 2017-11-27
激光冲击强化技术原理及研究发展
Research and development of laser shock processing technology
激光冲击强化 表面处理 残余应力层 纳米晶 等离子体冲击波 塑性变形 laser shock processing surface strengthening residual stress layer nanocrystalline plasma shock wave plastic deformation
摘要
激光冲击强化技术(LSP)是一种新型的激光应用表面处理技术。与传统表面改性技术相比,激光冲击强化技术能给材料带来更深的残余应力层,使材料表层晶粒细化甚至出现纳米晶,同时大幅提高材料的疲劳寿命。利用高能激光辐照约束层材料(黑漆、黑胶带或铝箔),约束层材料在瞬间熔融气化并产生高温高压的等离子体。等离子体冲击波是一种爆轰波,可以通过C-J模型计算冲击波的峰值压力。等离子体冲击波在约束层(水、光学玻璃)的约束下向材料内部传播,其压力远远超过了材料的弹性屈服极限,材料经历了弹性-塑性变形,最终材料表面形成稳定的残余应力场并发生微弱的塑性变形。本文介绍了激光冲击强化技术的研究发展历程,在此基础上对该技术发展方向进行了展望。
Abstract
Laser shock processing (LSP) is a new and efficient type of laser surface treatment technologies. Compared with the traditional surface modification technologies, laser shock processing can form a deeper re-sidual stress layer to the material and make surface grain refinement or even appear nano-crystalline, mean-while significantly improving the fatigue life of the material. When the high-energy laser irradiates at the con-finement layer (black paint, black tape or aluminum foil), the material of the confinement layer is instantaneously melted and gasified to produce a high-temperature and high-pressure plasma. The plasma shock wave is a detonation wave that can be used to calculate the peak pressure of the shock wave by the C-J model. The plas-ma propagates to the interior of the material under the constraint of the confinement layer (water or optical glass). The pressure of the shock wave far exceeds the elastic yield limit of the material. Therefore, the material under-goes elastic-plastic deformation and eventually forms a stable residual stress field and a slight plastic defor-mation. The development of the technology research process is also introduced. On this basis, the development direction of the technology is forecasted. Key
李松夏, 乔红超, 赵吉宾, 陆莹. 激光冲击强化技术原理及研究发展[J]. 光电工程, 2017, 44(6): 569. Songxia Li, Hongchao Qiao, Jibin Zhao, Ying Lu. Research and development of laser shock processing technology[J]. Opto-Electronic Engineering, 2017, 44(6): 569.