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In this paper, finite element (FE) simulation for high-speed milling of aluminum alloy was performed using a ductile fracture model with Mohr-Coulomb criterion proposed by Bai and Wierzbicki (BW). To verify the model, predicted cutting forces were compared to experimental results in the same cutting conditions. Then, further simulations were performed to estimate the cutting forces and chip shrinkage coefficients subjected to different cutting parameters such as cutting speeds, cutting depths, and clearance angles of a cutting tool. The obtained results were also used to determine optimal cutting parameters using the Taguchi method. The analysis of variance (ANOVA) was employed to investigate the influence percentage of each cutting parameter on cutting force and chip shrinkage coefficient. The simulation results showed that inclusion of strain rate in numerical model significantly improved the accuracy of estimated cutting force in comparison to experiment. The optimum values obtained for high-milling process were cutting speed 1000 m/min, cutting depth 1 mm, clearance angle 15°, and rake angle 4°. [ABSTRACT FROM AUTHOR]

AZ31 magnesium alloy sheets are usually performed at high temperatures of 200-250°C due to their unusual hexagonal close-packed structure and low ductility at room temperature. In this study, to predict V-bending/unbending spring-back of AZ31 magnesium alloy sheets subjected to high temperatures, a modified kinematic/isotropic hardening model considering the unusual plastic behavior of the magnesium alloy sheets, which follow the modified Johnson-Cook (JC) model, was used by way of a user-material subroutine, using an explicit finite element code. The simulation results from the modified hardening model at room temperature are compared with measurements of tension/compression and compression/tension tests. The modified JC model was then applied to predict tension/compression and compression/tension curves at high temperatures. Finally, an actual V-bending/unbending process for an AZ31 magnesium alloy sheet at high temperatures was performed to verify the spring-back angle, and this angle was then compared with spring-back angle predictions of the FE simulation. The proposed hardening model showed good agreement between simulation results and corresponding experiments. [ABSTRACT FROM AUTHOR]