The Study Of Small Holes On Micro Cutting

In recent years,with the continuous improvement and development of science and technology,precision small holes have been widely used in aerospace,national defense,electronic industry and other fields,especially in some occasion where precision machinery parts are used.It has been paid much attention to the quality requirements of the processing and manufacture of precision small holes.At present,micro cutting technology is still the main machining methods and means in the field of micro machining.It is closely related to the characteristics of micro cutting technology,which are good economy,high efficiency and low energy consumption.Meanwhile,micro cutting can achieve the machining of small parts and device of complex three-dimensional structure and surface features which are only tens of microns to millimeters in size.Therefore,the machining and manufacturing of precision small holes also adopts micro cutting method generally.Aiming at micro cutting of the precise small holes,this paper conducts the finite element simulations and the cutting experiments of micro drilling and micro helical milling respectively.The critical cutting parameters of the minimum undeformed chip thickness(MUCT)are obtained for the two different ways of machining technology.Meanwhile,the optimal machining method and the optimal cutting parameters of micro cutting small holes are acquired by analyzing chip formation,cutting force and burrs in micro cutting small holes process.Firstly,the finite element models and the simulations of micro drilling and micro helical milling are conducted respectively.The research and the analysis are carried out for the cutting parameters,chip morphology and cutting characteristics of the two kinds of machining methods considering the requirements of micro cutting small holes.The reasonable finite element models are created for micro cutting tool and the workpiece based on Deform-3D software.And the finite element simulations of micro drilling and micro helical milling are proceeded by selecting different cutting parameters values.According to the analysis of chip formation and cutting force,the critical cutting parameter values of the MUCT are obtained in the simulation.Secondly,micro cutting experiments are performed for the two kinds of machining methods: micro drilling and micro helical milling.Based on the simulation results,this article conducts the micro cutting experiments by selecting reasonable cutting parameters,machining equipment and tools.The critical cutting parameter values of the MUCT are judged for the two kinds of processing modes.Meanwhile,the reliability and the rationality of the simulations are verified.Through the comparative study of two kinds of processing methods,the optimal machining method of micro cutting small holes are obtained.Based on the above simulations and cutting experiments,the optimization experiments of micro cutting small holes are performed.By using orthogonal experiment method of multi-factor,the different micro cutting parameters are selected and combined reasonably.And the experiments of micro cutting small holes for the research material are proceeded.The optimized cutting parameters are obtained by analysing the cutting force and the burrs in experiments.Based on the summary of micro cutting experiments,the study provides some reference and research basis for the subsequent micro machining of precision holes.