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The generation mechanism of machininginduced residual stresses is a complex nonlinear and thermal-mechanical coupling problem. The cutting forces and cutting temperature produced in machining process must be considered simultaneously. The influence of cutter orientation and feed per tooth on the cutting speed, cutting forces, cutting temperature, and residual stresses is discussed in the present study. Effective cutting speed in accordance with the inclination angle in feed direction is analyzed. The cutting forces are gained by milling experiment, and the cutting temperature is obtained by finite element method. Moreover, the influence of the effective cutting speed on the cutting forces and cutting temperature is stated, and the relationship among the cutting forces, cutting temperature, and residual stresses is discussed. The experimental and numerical methods are both adopted in this study to give a better understanding of the milling process. After analysis of the phenomenon, several conclusions are made. The inclination angle in feed direction affects the effective cutting speed, and then the cutting forces, cutting temperature, and residual stresses are affected. Priority selection of inclination angle in feed direction is suggested from 5°to 30°in order to reduce the cutting forces. The overall trend of the workpiece temperature presents the parabolic shape, while the chip temperature increases with the increasing inclination angle in feed direction. Residual stress in feed direction almost increases with the increasing feed per tooth, which is not obvious in the general scope of the feed rate. The inclination angle of 5°and 15°is the priority in order to produce residual compressive stresses in cross feed direction.

This paper describes the development of a simulation model for ball end milling with inclination angle based on a finite element method. The Johnson–Cook model and isotropic hardening rule were used to describe the properties of the workpiece material, and re-meshing technology was adopted to obtain accurate results. The Cockcroft–Latham criteria rule was used to determine the chip formation. The ball end mill was modelled, and then imported into a finite element analysis system for simulation of machining process. The heat conducted into the cutter was taken into account in the present simulation, giving a better accordance with the actual machining process. Thirty combinations of cutting parameters and inclination angle of the ball end milling process were simulated in the finite element environment, and the corresponding ball end milling experiments were conducted in a five-axis machine. Evolution of the chip and the effective stress predicted in the shear zone during simulation were presented. The cutting forces derived from the simulation were compared with the experimental results, and the overall trend of the maximum cutting forces in each direction showed a good agreement with the experimentally measured values. The potential possibility to study five-axis ball end milling with both inclination angle in feed and cross-feed direction was pointed out.