A Calculating Method Of Dot To Dot And Process Design Of The Surface Error In Milling

In efficient milling of large structural parts,due to the dynamic influence of cutter tooth error and milling vibration,the formation process of machined surface is constantly changing,which leads to a variety of variation characteristics of machined surface error along the feed speed direction and cutting depth direction,and then has an impact on the bonding performance of machined surface.The existing measurement methods evaluate the overall or local level of the machined surface quality,and there are still fuzziness and uncertainty in the research on the specific variation characteristics of the machining error on the machined surface,which affect the control of the machined surface accuracy.Therefore,the research of machining accuracy consistency is of great significance.With the support of the National Natural Science Foundation of China(51875145)and the key project of Heilongjiang Natural Science Foundation(zd2020e008),in order to achieve the consistency of machining surface accuracy and improve milling energy efficiency,this paper studies the point-to-point calculation and process design method of machining surface error combined with end mill milling experiment.Because the existing evaluation methods use the maximum error value as the evaluation index of machined surface quality,it can not reveal the formation process of machined surface error,and its characterization is limited to the overall level or local level.Therefore,a point-to-point solution method of machined surface error is proposed.By constructing the fitting equation of machined surface,the error of any position on the machined surface is solved point by point,and the machining error is analyzed The results show that there are various characteristics along the feed speed direction and cutting depth direction on the surface,and the milling experiment of titanium alloy is carried out with a 5-tooth cemented carbide end mill with a diameter of 20 mm.According to the milling experiment of end mill,the influence of cutter tooth error and milling vibration on the forming process of machined surface is analyzed.The micro element method is used to simulate the cutting path of milling cutter,and the accuracy of simulation is verified by the point-to-point calculation method of machined surface error.The identification method of influence characteristics of cutter tooth error and milling vibration on machined surface error is proposed,and the machining surface is simulated by simulation model The results show that the influence mechanism of various factors in the forming process of milling surface error is constantly changing.Through the analysis of the formation process of milling surface,the influence factors of machining surface error are screened,and the influence factors of vibration are analyzed by variance analysis,and the influence degree of each design variable on machining surface error is preliminarily determined.According to the central composite experimental design method,the experimental design is carried out,and the response surface model of machining surface error distribution characteristics is constructed to analyze the influence significance The 3D response surface of machined surface error to design variables is constructed to reveal the degree of interaction between design variables,and the results are different from the results of variance analysis,which shows that the interaction between various factors changes its independent effect,and provides the basis for the control of machined surface accuracy consistency.According to the results of milling experiment analysis and significance analysis,the hierarchical structure model of the influencing factors of machining surface accuracy is constructed,and the design variables of machining accuracy are extracted to re plan the design sequence.The improved grey correlation analysis method is used,combined with the function planning of the design variables of machining surface error variation characteristics,and the optimization method is proposed The process design method of machining surface accuracy consistency is put forward,based on which a new process scheme is proposed.After the simulation method is verified to be effective,the milling experiment is carried out to calculate the machining surface consistency.The results show that the process design method can effectively control the machining surface accuracy consistency.