Milling Accuracy Analysis Of Ball-End Milling Cutter And Reliability Optimization Of Milling Parameters

Ball end milling cutter is widely used in mechanical manufacturing industry,especially in manufacturing complex parts,because of its advantages of high efficiency and high accuracy of contour surface processing.However,due to the lack of in-depth study on milling mechanism and technology,its advantages can not be brought into full play in actual processing.Studying the milling force and the deforming error of the cutter in milling process can provide a reliable theoretical basis for formulating a reasonable process before milling.It is of great significance to improve the processing technology and product quality and reduce the cost.Based on the model of milling force and cutter error,the reliability and reliability sensitivity of milling accuracy are analyzed by Kriging method and Monte Carlo simulation,using the mechanical model of milling process and considering the influence of random factors in the process of milling,taking the rigid workpiece machined by double-edged ball-end milling cutter as the research object.The reliability optimization method of milling process parameters of ball end milling cutter is put forward.The main work is as follows:(1)Analyzing the modeling method of milling force and yield error of ball-end milling cutter,and considering the randomness of milling parameters in actual processing,based on Kriging model and Monte Carlo simulation,a prediction method of probability distribution of milling force and yield error of ball-end milling cutter is proposed.Compared with the deterministic method,the predicted results are more in line with the actual processing conditions.At the same time,the Kriging model is used to replace the numerical calculation,which greatly reduces the calculation time.(2)Kriging model is used to fit the approximate function expression between the cutter error and the milling parameters,and Monte Carlo method is used to calculate the reliability and reliability sensitivity of ball-end milling accuracy,which is verified by direct Monte Carlo method.By analyzing the results of reliability sensitivity,the degree of influence of milling parameters on cutter yield error is obtained,which provides a theoretical basis for improving milling accuracy.(3)Taking the highest productivity,the lowest processing cost and the minimum milling force as objective functions,and taking the quality requirements of machine tools,cutters and workpieces as constraints,as well as the reliability requirements of milling accuracy as constraints,the reliability optimization model of milling parameters for Ball-end Milling cutters is established,and the GlobalSearch method is adopted.The model is solved.Considering the above three objective functions and weighing their importance,multi-objective optimization of process parameters reliability of ball-end milling cutter is carried out by using linear weighted combination method,and ultimately the best comprehensive economic benefit is achieved.