应用激光, 2017, 37 (2): 276, 网络出版: 2017-06-08
测量-加工闭环控制的激光抛光聚晶金刚石工艺研究
Study on Laser Polishing Poly Crystalline Diamond by Closed-loop Control of Measurement and Processing
聚晶金刚石 闭环控制 测量-加工 激光抛光 激光位移传感器 polycrystalline diamond closed-loop control measurement-processing laser polishing laser displacement sensor
摘要
聚晶金刚石(PCD)坯料的传统平整加工工艺如机械磨削、电火花铣削、超声波磨削、激光铣削等, 工艺流程为开环控制, 难以达到超精密加工所要求的平整度和光洁度。将二维激光位移传感器与激光扫描振镜集成在同一加工头上, 与XYZ三轴工作台配合, 实现了在线测量PCD表面起伏形貌与自动分块激光扫描抛光的闭环工艺控制。研究了激光能量密度、光斑搭接率、扫描速度对抛光质量的影响。结果表明, 较小的激光能量密度、80%光斑搭接率、扫描速度为100 mm/s时, 可获得最佳的抛光效果。经过4次闭环抛光后, PCD坯料表面粗糙度Ra由40.7 μm降低到1.21 μm, 表面平面度由130 μm降低到30 μm, 抛光精度与机械精磨相仿, 测量-加工闭环控制具有显著的工程应用意义。
Abstract
The traditional polishing technologies of polycrystalline diamond blank such as mechanical grinding, electro-discharge milling, ultrasonic grinding, laser grinding are open-Loop control, and it is difficult to achieve the required flatness and finish. In this work, a closed-loop control of on-line measurement of PCD surface morphology and automatic block laser polishing is realized by integrating the two dimensional laser displacement sensor and laser scanning galvanometer scanner together in one processing head that mounted on a XYZ tri-axial worktable. The influence of the laser energy density, laser spot overlapping rate and scanning speed on polishing quality is studied. The results show that the best polishing quality can be obtained using the processing parameters of small laser energy density, 80% laser spot overlapping and the scanning speed of 100 mm/s. After 4 times polishing of closed-loop control procedures, the surface roughness of PCD blank decreased from 40.7 μm to 1.21 μm, and the surface flatness decreased from 130 μm to 30 μm. The polishing precision is similar to that of mechanical precision grinding which shows that the closed-loop control of measurement and processing has prominent significance for engineering applications.
何安, 曹宇, 姜小霞, 张健, 刘文文, 陈益丰. 测量-加工闭环控制的激光抛光聚晶金刚石工艺研究[J]. 应用激光, 2017, 37(2): 276. He An, Cao Yu, Jiang Xiaoxia, Zhang Jian, Liu Wenwen, Chen Yifeng. Study on Laser Polishing Poly Crystalline Diamond by Closed-loop Control of Measurement and Processing[J]. APPLIED LASER, 2017, 37(2): 276.