| With keen consideration on the needs of advanced manufacturing, the thesis deals with the physical modeling and simulation which is a key technology in Virtual Manufacturing in the process of milling. A milling force model for ball end milling in high speed milling is built basing on the theory of metal cutting, machine tool dynamics, cutting experiments and computer simulation.The modeling firstly considers the influence of cutting speed to the cutting mechanism in high speed cutting, and a force called the chip-force is introduced which is neglected in the case of low speed cutting, while the calculation process is elaborated as well. By analyzing the shape of cutting chips and the relationship between the cutting speed and shear angle in infinitesimal, relevant experimental data is obtained.In the infinitesimal milling force modeling, the milling force is considered to be constituted with the pressure and friction acting on the rake face and the flank face. The resultant force acting on rake face is constructed analytically, and coefficients of the pressure and friction on the flank face are identified from milling experiments.Finally, the coefficients of milling forces are identified from milling experiments, and the milling force is simulated and anticipated under different working conditions. The results of simulation and the actual measurements are closely matched up. Furthermore, the thesis makes perpendicular analysis on the experimental data, and collects the relevant information. The total milling force model is established on the basis of the study on cutting mechanism with the advantages of less experiments, higher accuracy and therefore is with strong adaptability.The work in this thesis will establish a solid foundation for improving process modeling in the Virtual Manufacturing theory, for improving the stability and security and machining quality in the milling process, and for developing the practical physical simulation system of milling process.
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