二维振镜超快激光高精加工球面等角螺旋槽研究  

High-Precision Machining of Spherical Equiangular Spiral Groove Using Two-Dimensional Galvanometer Ultrafast Laser System

作　　者：王文豪[1,2] 季凌飞[1,2] Wang Wenhao;Ji Lingfei(Institute of Laser Engineering,Faculty of Materials and Manufacturing,Beijing University of Technology,Beijing 100124,China;Key Laboratory of Trans-Scale Laser Manufacturing Technology,Ministry of Education,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学材料与制造学部激光工程研究院,北京100124 [2]北京工业大学跨尺度激光成型制造技术教育部重点实验室,北京100124

出　　处：《中国激光》2021年第14期159-168,共10页Chinese Journal of Lasers

基　　金：国家自然科学基金(51975017);北京市教委科技计划(KZ202110005012);2018国家重点研发计划(2018YFB1107500)。

摘　　要：为解决动压气浮轴承球面螺旋槽加工难度大的问题,提出一种基于Bézier曲面分割法的光斑重叠率补偿方法。通过研究平均功率、扫描速度、离焦量对TN85金属陶瓷激光刻蚀深度和宽度的影响,确定优化参数;采用1064 nm波长的皮秒激光配以二维x-y扫描振镜,在TN85金属陶瓷球面上完成了粗糙度Ra约为65 nm、深度为(4±1)μm、高度落差为4.5 mm的12条圆周分布螺旋槽阵列加工,加工时间小于10 min。所提方法实现了激光二维振镜对曲面螺旋刻槽深度可控的高精加工,兼顾精度效率,具有良好的工程化应用优势和发展前景。Objective The dynamic pressure air bearing has the characteristics of complex structure and demands of high manufacturing accuracy. To improve the bearing capacity, it is necessary to machine a series of equiangular spiral grooves with depths of(4±1) μm and a helix angle of 22° around the spherical surface on the hemispherical bearing. At present, ion-etching methods are employed to realize such processing but must through high-precision mask, as well as with high environmental requirements, complex processes, and low efficiency. Processing of high-precision mask has its own challenges. Laser processing technology is an effective supply of maskless processing. The cooperation of a laser beam and a five-axis linkage computer numerical control machine tool can solve a three-dimensional space processing problem but with complex processes and high cost. For a normal laser processing system using a common two-dimensional(2D) galvanometer, the key point is to seek a breakthrough in the processing track to achieve high-precision machining of curved surfaces with great curvature variation, such as the grooving of the dynamic pressure air bearing. In this study, we present a processing method of an equiangular spiral groove on a spherical surface by picosecond laser using a 2D galvanometer. The basic strategy and findings of this study may be helpful for high-precision grooving of parts with curved surfaces by just using a common 2D galvanometer ultrafast laser system.Methods A 1064-nm wavelength picosecond(ps)laser processing system equipped with a 2 D scanning galvanometer was employed to process equiangular spiral grooves on the curve surface of TN85 cermet spherical parts.The etching size and roughness were measured by a laser confocal microscope and a profiler.By the experiments of ps laser etching of the flat surface of the cermet parts,the process parameters that can meet the depth requirements with(4±1)μm microgroove were determined.Then,based on the process parameters,the TN85 cermet spherical surface was et

关 键 词：超快光学 材料加工 球面 螺旋槽 激光 光斑重叠率 

分 类 号：TN249[电子电信—物理电子学]