Multi-objective Optimization Research On Milling Parameters Of Free-cutting End-milling Cutter

Milling,as one of the most basic machining methods,plays an important role in the whole machining industry.At present,problems still exist in the process of metal milling,such as low milling accuracy,low milling efficiency and high milling temperature.In order to solve the above problems,free cutting step end milling cutter is put forward.Compared with non-free cutting end milling cutter,it has the advantages of high milling efficiency,low milling temperature and small chip deformation.In this paper,free-cutting stepped end milling cutter is used to explore the influence of milling process parameters on milling performance by combining finite element simulation and milling test,thus realizing high quality and high efficiency milling.It is divided into the following points:(2)Finite element simulation of cutting A3 steel with three-step free-cutting end-milling cutter is carried out by using ABAQUS simulation software.By comparing the cutting simulation results of free-cutting end-milling cutter and non-free-cutting end-milling cutter,it is concluded that under the same cutting parameters,the milling force and milling temperature of three-step free-cutting end-milling cutter are much less than that of non-free-cutting end-milling cutter,the milling force and milling temperature are reduced by 30% and 17%.Secondly,the influence law of three factors on milling force and temperature is explored by single factor test,and the primary and secondary effects of three factors on milling force and temperature are explored by three factors and four levels orthogonal test,and the optimal parameters are obtained when milling force and temperature are the smallest respectively.Based on the test data of milling force and milling temperature,the mathematical regression model of milling force and milling temperature for milling A3 steel with three-step free-cutting end-milling cutter is obtained.(2)Milling experiments were carried out with two-step free-cutting end-milling cutter,and surface roughness values corresponding to each group of tests were recorded.A second-order polynomial mathematical prediction model for surface roughness was established and variance analysis was carried out.Secondly,the influence of various parameters on surface roughness can be clearly seen from the 3D response surface map by the combination of number and shape,which is consistent with the results of ANOVA.The advantages of the two-step free-cutting end milling cutter are verified.When the cutter is used for milling,the surface roughness of the workpiece is better.(3)The genetic algorithm is used to optimize the cutting parameters with the aim of roughness and milling efficiency.An optimization model is established,which includes optimization objectives,optimization variables and constraints.Finally,the genetic algorithm toolbox in MATLAB is called to carry out iteration calculation and obtain the global optimal solution,which provides the reference value of cutting parameters for free-step end milling cutter cutting.