The Design And Manufacture Of Circular Milling Cutter With Skewing Chamfer And The Experimental Study On Cutting Performance

Large car cover pieces hardened steel mold have the characteristics of high hardness and difficult machining,after Hardened steel spliced into the whole mold,due to the existence of joint area and hardness difference,the tool can be regarded as intermittent cutting condition in cutting seam,suffering from frequent shocks and cause violent vibration,thereby increasing the wear and deformation of the tool,so that the surface quality of mosaic area is difficult to guarantee,for hardened steel pieces especially on slit regional performance becomes an urgent problem to solve for today's car panel parts,therefore,a circular milling cutter with skewing chamfer is proposed and designed in this paper,and the related experimental research is carried out for the above problems.Firstly,based on the study of geometric structure,milling speed,cutting bandwidth and residual height of circular milling cutter with skewing chamfer,and the advantages of the designed cutters are analyzed in principle.The geometric model of circular milling cutter with skewing chamfer and the equation of the edge and chamfer face are established,combined with MATLAB simulation software,verifying the correctness of the geometric model,the edge model and the accuracy of the multi segment arc edge connection area.Then,study on the grinding test of milling cutter,and the specific tool manufacturing scheme is given in combination with the grinding process,and the analysis and optimization are carried out from the aspects of machine tool and grinding wheel.According to the structure of the designed tool,the section of the groove is divided into a certain number of discrete curves,based on the calculated each discrete boundary point of curve fitting to control the shape of a spiral groove,and establish the UG simulation system verify the accuracy of the calculation method,and make use of the five axis grinder grinding,analyzes the possible problems and solutions in the process of grinding.finally,the method of measuring the spiral angle of the milling cutter,the angle and width of the chamfering,the position of the center and the grinding precision of the cutting edge is proposed.Finally,the experiments of milling hardened steel splicing parts are designed,and the comparative study on cutting force,tool wear and surface quality of circular milling cutter with skewing chamfer and ball end milling cutter is carried out.It is found that both the axial force and the radial force peak at the splicing gap are larger than those of the ball milling cutter.but the axial force and the radial force abrupt degree are far lower than ball head milling cutter,and have higher processing stability.The rake face has a certain range of heat-affected areas,and the wear is mainly concentrated on the chamfering surface and the rear face,It can effectively reduce the production of cutting edge and improve the anti-damage performance of the cutting tool.The wear of the front tool surface is mainly oxidation and diffusion wear.The wear of the rear tool surface is mainly abrasive wear and coating failure,and with the increase of wear amount,the mechanism of oxidation,diffusion and so on appears.The surface morphology,height difference and extrusion damage area of the two ends of the slit are superior to those of the ball end milling cutter,and the quality of the machined surface is better than that of the ball milling cutter.