纳秒激光抛光表面的波纹形成机理  

Formation Mechanism of Ripple on Nanosecond Laser Polished Surface

作　　者：李健[1,2] 赵珂 金卫凤[3] Li Jian;Zhao Ke;Jin Weifeng(School of Materials Science and Engineering,Jiangsu University,Jiangsu 212013,China;Research Institute of Intelligent and Flexible Mechatronics,Jiangsu University,Jiangsu 212013,China;School of Mechanical Engineering,Jiangsu University,Jiangsu 212013,China)

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013 [2]江苏大学智能柔性机械电子研究院,江苏镇江212013 [3]江苏大学机械工程学院,江苏镇江212013

出　　处：《应用激光》2022年第1期69-75,共7页Applied Laser

基　　金：国家自然科学基金(51775248);江苏大学高级人才启动基金项目(自然类)(11JDG101)。

摘　　要：为探究激光抛光中引入的波纹的形成原因,通过纳秒光纤激光对718合金和304不锈钢进行了激光抛光,考察激光抛光导致的波纹效应。结果表明:激光抛光产生的波纹(尺度为数十微米)与激光脉冲作用间距(10μm)差别较大;不同激光能量产生的波纹在幅度上有差别,波纹的振幅随激光能量的减小而减小;波纹波长随激光能量的变化不大,具有一定的稳定性。根据试验结果,波纹的产生是涉及材料对激光能量的吸收、熔体流动、材料蒸发甚至脉冲时序的复杂过程,其根源在于激光交替作用于熔体和高温固体而产生的熔体流动差别。激光能量对波纹的影响机理为:激光能量过高时,由于输入能量部分以熔体气化的方式消耗掉,熔体厚度增大不明显,波纹随能量的变化不大;在产生气化较少的能量范围,激光能量的降低将导致熔体厚度减小,产生的波纹幅度减小。In order to explore the ripple formation mechanism in laser polishing,718 Alloy and 304 stainless steel were polished by nanosecond fiber laser,and the ripple effect caused by laser polishing was investigated.Results show that there is a great difference between the ripple produced by laser polishing(the scale is tens of microns) and the laser pulse action distance(10 μm).Moreover,the ripple amplitude decreases with the decrease of laser energy,while the wavelength of the ripple changes little with the laser energy.According to the experimental results,the generation of ripple is a complex process involving the absorption of laser energy,melt flow,material evaporation and even pulse sequence.The source of ripple is the variation of melt flow caused by the laser ablation alternately to the melt and high temperature solid.The influence mechanism of laser energy on ripple is as follows:when a very high energy laser pulse is used,the input energy would be consumed by melt gasification,thus the increase of melt thickness as well as the ripple changes very little with energy.When the laser energy is in the range with less gasification,the decrease of laser energy would lead to the decrease of melt thickness as well as ripple amplitude.

关 键 词：激光抛光 波纹 纳秒脉冲激光 激光功率 波纹波长 

分 类 号：TN249[电子电信—物理电子学]