Research On Parametric Modeling And Geometry Structure Parameters Of End Mills

End milling is the most important method in high speed cutting process. The structure parameters of end milling cutter have a direct effect on the cutting forces and temperature, so,to determine a set of reasonable structure parameters becomes one of the most important factors concerned with production machining quality.The traditional tool designbased on empirical design method requires repeated process to design, to trail-produced, to trail-cut and other processes, which results in a long development cycle and high cost.Parametric models of special types of end mills are researched. High speedcarbide end mills used to machining Ti6A14Vstructure parts for aviationare taken as concrete study object. Through cutting simulation and modal analysis, the reasonable design parameters of end mills are determined. Therefore, based on dynamic and static characteristic analysis, themethod of determining reasonable design parameters for special types ofend millsis formed.The main work of this paper is summarized as follows:(1) Through analysis of the main design parameters, a mathematical modeling methodand its model for helix cutting edge, linear cutting edge, arc-shaped cutting edge and transverse section of end mills with variable pitch, various helix and non-constant groove depth are established. Based on the mathematical modeling and mathematical model, feature classes for end mills model are constructed using object-oriented approach. Then each feature is formed based on multi-sections solid lofting techniques and all features are merged based on geometrical set Boolean techniques. After that the completed parametric geometry of end mill is formed.(2) The basic issues in physics simulation for metal cutting, including the finite element method, the material constitutive model, the chip and the workpiece separating criterion, the friction theories between the chip and the workpiece and methods are discussed. Based on AdvantEdge FEM software, the end mill geometry model is imported to AdvantEdge FEM software and the milling physical simulation model is established for milling the pocket of titanium alloy after setting appropriate simulation boundary conditions.Then cutting forces of three directions, tool temperature, tool stress field and other physical quantities are calculated. At last, the milling cutting forces from simulation are compared with the forces from milling experiment to validate the simulation model and geometry model of end mills.(3) On the basis of physical simulation model for milling and on account of finish side milling Ti6A14V titanium pocket, the impact of a single factor, including helix angle, rake angle, clearance angle, the number of teeth, on the cutting forces and temperatures is discussed. Then helix angle, rake angle, the relief angle and the number of teeth of end mill for minimal cutting force and temperature are obtained.(4) Characteristic properties of special structure end mills suitable for high speed milling are analyzed. The impact of different special parameters on the Characteristic properties is discussed. Then the best parameters for each kind special end mill are obtained, then a end mill with all of the three special structures is analyzed. The result can provide a reference for the spindle speed for various mills.