Research On Fabrication Of Microstructure Abrasive Tool With Uniform Abrasive Particles Based On Electrostatic Spray Deposition

At present,microstructure surface is widely used in optics,microchannel chips and functional surfaces.When there are defects such as burr or indentation,the surface function of microstructure is limited.It is necessary to finish the microstructure to improve its surface finish.However,it is one of the most difficult problems to prepare the microstructure abrasive tool with uniform distribution of abrasive particles,controllable shape and short preparation period.Therefore,a new method of micro structured abrasive tool with uniform particle size distribution is proposed based on Electrostatic Spray Deposition(ESD).It provides a new idea for finishing micro structure.The principle and existing problems of micro abrasive tool are discussed through simulation analysis and experimental research.(1)The mechanism of ESD was discussed from the jet area,corrugated area and atomizing area.The droplet deposition mode was studied.The process and problem existing in the fabrication of microstructure abrasive tool by ESD were described,and The solution to explore the reasonable process parameters and the size of the microgroove was put forward.(2)Two dimensional simulation model of ESD for microgroove was established by COMSOL Multiphysics.The electric field characteristics and spray characteristics under capillary nozzle-ring electrode configuration were studied,and the deposition characteristics of droplets on substrates or microgroove were revealed.The reasonable experimental parameters were obtained,such as microgroove height?1 mm,microgroove height width ratio?1,microgroove distance from jet center?3.5 mm,static voltage?-6 k V and receiving distance?40 mm.(3)The experiment platform of ESD was built by selecting micro-injection pump,electrostatic generator and UV light.Electrostatic liquid was prepared by using light curing resin,polysorbate-80,kerosene and diamond single crystal powder.The MS-603 spray was used as the release material for microstructure abrasive tool.The reasonable parameters of the microgroove obtained by simulation were verified,and the solution to the droplet backflow and incomplete solidification were proposed.(4)By comparing and analyzing the advantages and disadvantages of the grid-counting method and the intercept method,the Dirichlet tessellation was proposed to evaluate the uniformity of the abrasive particles distribution,and obtained the conclusion that the uniformity of the abrasive particles within the radius of 2.5 mm of the spray center was more than 70%.A thin layer with or without microstructure abrasive tool was prepared by ESD.It was found that the thickness difference between the center of the thin layer and the edge of the without microstructure abrasive tool was directly proportional to the spray time,which verifies the correctness of the simulation.The tensile length of the thin layer spline of 8 mm without any fillers was 0.097 mm.Finally,according to the reasonable parameters of the simulation,the array microstructure abrasive tool with dimensions of 10×10 mm~2,microgroove distance of3 mm,microgroove height width ratio of 1/4,1/2 and 1 were successfully prepared.The deviation rate between the micro characteristics of the abrasives tool and the microgroove height of the workpiece was lower than 1.09%,the deviation rate of width was lower than2.87%,and the micro characteristics of the abrasives tool were completely formed.