Research On The Dynamics And Reliability Of Thin Wall Milling

Thin-walled components are widely used in the fields of automobiles and ships because of their light weight and other excellent properties.The milling flutter and dynamic machining error in the process of thin-wall component machining will reduce the machining efficiency and precision of the machine tool.The influence of milling parameters on the machining system was studied and analyzed.The milling parameters were selected reasonably to ensure the stability of milling,and the influence of milling flutter and dynamic machining error on the machining system was reduced.In this paper,the vibration problem of thin-walled parts milling is studied.Kriging method is used to carry out the reliability sensitivity analysis,considering the randomness of the milling parameters,the reliability sensitivity as a measure of the milling parameters,evaluation of milling parameters on the stability of milling thin-walled components and surface degree of the influence of position error,the choice of cutting parameters for high-speed milling thin-walled components to provide reasonable theory basis.The specific content of the paper is as follows:Firstly,stability and dynamic machining error analysis of thin-walled parts.Thin-walled milling dynamics model building,the milling of two dimensional stability lobes diagram and analyze the effects of milling parameters on the milling stability,according to different processing phase of thin-walled milling process three dimensional stability of pictorial diagram,the choice of cutting parameters for high-speed milling thin-walled components to provide reasonable theory basis.The dynamic machining error caused by forced vibration is predicted by frequency domain method and the influence of random factors on dynamic machining error is studied.Based on the surface roughness theory,the influences of axial cutting depth,feed per tooth and diameter of milling cutter on surface roughness were analyzed,which provided a reasonable theoretical basis for selecting cutting parameters for high-speed milling of thin-walled members.Secondly,milling reliability calculation and reliability sensitivity analysis based on Kriging method.Kriging method for thin-walled milling agent model of dynamic model,considering the random uncertainty factors influence on milling process,based on Kriging method for reliability sensitivity analysis,the reliability sensitivity as a measure of the milling parameters,evaluation of milling parameters on the stability of milling thin-walled components and surface degree of the influence of position error,the choice of cutting parameters for high-speed milling thin-walled components to provide reasonable theory basis.Thirdly,the reliability optimization design of the milling system parameters.The reliability optimization design of the milling system is carried out,the surface position error and maximum production efficiency are taken as objective functions,the optimization model is established with milling parameters,stability and reliability as constraint conditions,and the parameter optimization design is carried out with the nonlinear programming genetic algorithm.