静电喷雾磨粒均布微结构磨具原位制备研究

In-situ Fabrication of Microstructure Tool with Abrasive Uniform by Electrostatic Spray Deposition

提出一种基于静电喷雾的磨粒均布微结构磨具原位制备方法。使用COMSOL Multiphysics中的AC/DC模块与粒子追踪模块建立静电喷雾微槽二维仿真模型,研究在喷嘴-环形电极配置下的电场特性、喷雾特性以及沉积特性,获得微槽深径比≤1,微槽深度≤1 mm,静电压≤-6 kV以及接收距离≥40 mm的优化参数。利用光固化树脂、聚山梨酯-80以及煤油按4:3:1的比例制备静电液,并添加单晶金刚石磨粒进行静电喷雾。创新性地利用狄利克雷镶嵌法定量评估不同喷射时间、不同径向位置的磨粒分布均匀度,以喷射中心半径2.5 mm范围内磨粒分布均匀度在70%以上,得到合适的微结构模具尺寸。通过分析微槽深度和宽度对沉积率的影响获得合理的微槽参数。原位制备得到的微结构磨具微观特征完整,磨具与工件微槽宽度偏差率为≤2.87%,高度偏差率为≤1.09%。利用静电喷雾制备微结构磨具具有磨粒均布、形态可控等特点,该方法为微结构表面加工提供新工艺与新思路。

A method of in-situ fabrication of microstructure tool with abrasive uniform by ESD is proposed. Two dimensional simulation model of electrostatic spray microgroove is established by using AC/DC module and particle tracking module in COMSOL Multiphysics. The electric field characteristics, spray characteristics and deposition characteristics under nozzle-ring electrodes are studied. The optimized parameters of microgroove height to width ratio ≤1, micro channel depth ≤1 mm, electrostatic voltage ≤-6 kV and receiving distance ≥40 mm are obtained. The static liquid is prepared by light curing resin, polysorbate-80 and kerosene in the proportion of 4:3:1, and the single crystal diamond powder is added for electrostatic spraying. Dirichlet tessellation is used to evaluate the distribution uniformity of abrasive particles in different injection time and radial positions. It was concluded that the distribution uniformity of abrasive particles is more than 70% in the radius range of 2.5 mm with the injection center to obtain the appropriate size of the microstructure tool. The reasonable parameters of the microgroove are obtained by analyzing the influence of the depth and width of the microstructure on the deposition rate. The microstructural characteristics of the abrasive tool are complete. The deviation between the microgroove width of the abrasive tool and the workpiece is ≤2.87%, and the height deviation is ≤1.09%. The in-situ fabrication of microstructure abrasives tool by ESD has the characteristics with uniform distribution of abrasive particles and controllable morphology. This method provides a new idea and technology for microstructure surface machining.