| With the complex surface mold and high-speed milling technology widely used in power machinery,aerospace,military manufacturing,automotive,light industry and other fields.At present,most researches on high-speed milling and finishing of mold steel complex surfaces focus on the influence of cutting parameters and tool wear on surface roughness,and the mathematical model for establishing milling force.There is less research on the cutting mode selection of Bezier surface and the standard deviation of the deviation between the finished surface and the ideal smooth surface.Therefore,the selection of the cutting mode and the determination of the prediction model of the surface standard deviation play an important role in the actual production of the finished surface quality.In this paper,the Bezier surface workpiece is taken as the research object.The optimal selection test of the finishing cutting mode,the prediction model of the surface standard deviation and the optimization of the milling parameters are carried out.1、The high-speed milling finishing test of the P20(3Cr2Mo)die steel Bezier surface workpiece in the NX processing module was carried out by using the carbide ball-end milling cutter.The cutting mode of the tool path was manually selected,and the standard deviation of the surface was used as the index.The actual machining verified.Compared with the other two cutting modes,the peripheral milling mode can reduce the fluctuation of the Bezier surface deviation value to a certain extent,and the surface quality is higher.2、In the environment of the peripherally milled Bezier surface workpiece,the standard deviation of the surface deviation values of the milling speed v_c,the feed per tooth f_z and the row a_e are analyzed by the range analysis and variance analysis of the orthogonal test.The size of the impact,the significance of the impact and the optimal combination of milling parameters.3、The single factor test method is adopted,the milling parameters are used as the processing factors,and the standard deviation of the surface is taken as the index.The standard deviation prediction model of Bezier surface is established,and the established prediction model is highly significant and has high reliability.4、The genetic algorithm is used to optimize the three milling parameters with the minimum surface standard deviation as the target,and the minimum surface standard deviation and the corresponding cutting speed,feed per tooth and line spacing are obtained.Comparing the standard deviation of the optimal milling parameter combination of the orthogonal test range analysis shows that the standard deviation of the genetic algorithm is smaller and the precision is higher.The surface quality of the finishing is better by using this milling parameter. |
