Simulation And Experimental Research On The Surface Topography Of Ball-end Milling Cutter

As an important aspect of surface quality,surface topography features have an important impact on the performance of parts.At the same time,with the increasing proportion of irregular surfaces in industrial products,more and more attention has been paid to the modeling and simulation of part surface topography formation process.With the support of multi-axis CNC technology and high-speed cutting technology,it has become possible to achieve the final machining requirements of the parts directly by precision milling with ball-end milling cutters.In this case,the modeling and simulation of milling surface topography of ball-end milling cutters has positive practical significance for the selection and optimization of cutting parameters in actual machining.Based on the formation mechanism of the ball-end milling surface topography,the paper uses the principle of homogeneous coordinate matrix transformation to construct the mathematical expression of the relative position relationship between cutter tooth cutting point and workpiece during the cutting process.On this basis,the simulation model of ball-end milling surface topography is established based on Z-MAP method.This model can not only realize the simulation of the surface morphology of plane parts,but also use the NURBS surface interpolation method,combined with CAM tool path planning and tool location retrieval algorithm,to achieve the matching of cutting time and tool location,and solve the problem that it is difficult to describe the tool path in time domain on complex surfaces,and then realize the simulation of the surface topography of free-form surface parts.The model can not only comprehensively consider the effects of spindle speed,feed speed,tool parameters,tool axis inclination and tool eccentricity,but also reflect the influence of surface shape characteristics and curvature changes on surface quality,which can better predict the ball-end milling surface morphology.On this basis,based on the developed simulation system,single-factor and mulit-factor simulation analysis is carried out to analyze the influence rules of parameters such as line spacing,feed per tooth,tool radius and tool axis inclination on the surface morphology and roughness of ball-end milling cutter,and a roughness regression model is established to provide a basis for the selection of parameters in practical machining.Finally,the ball-end milling cutter is selected to carry out the confirmatory milling experiments of spherical and sinusoidal surfaces on aviation aluminum alloy specimens.The comparison between simulation and test results shows that the simulation model is effective.