Study On Cutting Force Model Of Ball End Mill And Affect On Surface Quality In Five Axis Machining Center

The applicability in milling free-form surface of ball end mill had made it be the main tool in machining center. The cutting force characterizations of tool system are important to operating features and processing properties of machine tool. Therefore, the foundation of ball end mill cutting force model is very important for improving machining accuracy and reliability analysis of machine tool.Base on the blade line and structural features, ball end mill can be divided into many cutting elements. Local cuting force can be gotten by element cutting force through coordinate transformation, then the milling force prediction model about ball end mill was established. By studying on the ball milling force model and simplified method of the parameters, the simplified formula to the whole cutting force of ball end mills was given under a special condition in this study. Five axis machining center and milling dynamometer was used in cutting forces measurement experiment, then used the experimental data to recognize linear regression method, and determined the Cutting coefficient. Results of the experimental validation proved that the simulation results of the model well matched with the experimental values. And through the experiments we got the change rules of the cutting force in milling groove surface, cant, spherical surface and impeller surface.Considering the milling forces’ influence on machining accuracy, the tool deformation model which caused by cutting force was established. The influences to the processing tolerance accuracy caused by the tool deformation, the radial beat, the cutting heat and the tool wear were analyzed. With the finite elements software ANSYS and the experimental data, the static structural analysis and modal analysis of ball end mill is calculated, and got the displacement and won mises stress field chart, the former six inherent frequency and vibration model of ball end mill.In milling process, surface topography is a signifigent factor that directly affects the surface integrity and constitutes a supplement to the form errors which assoeiated with the workpiece deformation. Though the experiment research, the main factors of influences surface roughness were analyzed. And the influence law on surface roughness of rotate speed, cutting depth and rotating feeding were founded. All this can provide some help with chooseing milling parameters of the ball end mill.