Research On Surface Quality And Machining Precision Control Of Micro Structure Based On Micro Milling

Currently,the micro miniaturization of products turns into a significant developing direction of modern manufacturing industry,an increasing number of micro-parts are used in various fields including biological medical,instrumentation and micro robot.New processing technology arises at the historic moment,the emergence of micro cutting technology fills the manufacturing blank page between the micro and the macro.Micro milling becomes a mainstream method with its own advantages in cutting.Mesoscale milling has become a hot research field in micro manufacturing industry.The surface topography of milled workpieces often defines their performance.A series of phenomena those are different from conventional cutting have a significant effect on the final machining accuracy.In micro milling,it is a big challenge how to realize high quality and high efficiency machining of micro structure.Based on the previous research,the quality control of micro structural parts is deeply studied aimed at the problems of the microscale milling mechanism,the mesoscale surface topography and surface quality characterization,the mesoscale plastic deformation under multi coupling in this paper.The main research contents and results are as follows:(1)The new cutting edge trajectory model has been proposed,which considering the machining parameters,inclination of cutter,flutter,run-out,cutting force,and plastic deformation of the material.The surface topography and the roughness can be predicted and simulated accurately based on the theoretical model.By this model,the desired surface can be obtained and surface quality control should be achieved.(2)The fractal theory is applied to the mesoscale surface quality characterization in this paper.It has been investigated that the influence mechanism of fractal dimension,the relationship between the fractal dimension and the traditional surface roughness parameter Ra.Based on the study,it is clear that there is a one-to-one correspondence between fractal dimension and surface roughness,some effective improvement measures are put forward.(3)The model for calculating the plastic deformation of workpiece has been established during micro milling.The influence of the mesoscale cutting force and cutting heat is mainly considered based on energy method.In this model,the dimensional accuracy should be achieved by predicting the cutting force,cutting heat and workpiece plastic deformation.(4)Heat-resistance stainless steel has been chosen for micro surface and micro groove milling tests.Furthermore,some complex workpieces also have been processed with high quality.The all tests verify the accuracy of the models aforementioned.The research of this paper has some good practical significance.