The modeling and simulation of chip formation during high speed milling of hardened mold steel are systematically studied by the Finite Element Analysis (FEA). The modified Johnson-Cook’s constitutive equation for hardened mold steel is introduced. Comparing to the experimental results, the simulated results of cutting force, chip morphology, effective stress and cutting temperature in deformation zones of high speed peripheral milling indicate good consistence and the models established can be used to accurately predict the behavior of hardened mold steel.

SiCp/Al composite is widely used in the aerospace, electronics and automobile industries due to its ultrahigh strength and wear resistance. Surface integrity in the machining process can be influenced by tool corner radius. A finite element model is developed by DEFORM-2D to study on the effect of tool corner radius on residual stresses, cutting force and temperature in machining SiCp/Al composite process. The results show the large corner radius can improve cutting force, but hardly influence cutting temperature. Meanwhile, value of residual stresses is influenced by tool corner radius, but distribution of residual stress is not. The larger corner radius is, the greater the curve fluctuation of residual stresses is. And the large tool corner radius can effectively improve surface residual compressive stress.

When the pocket in die and mould is machined by high speed milling (HSM), the cutting forces increase and vibration fluctuates at the pocket corner because of the sudden change of cutting direction in general. It will cause serious wear and possible breakage of cutting tool, and poor quality of parts. By means of experiments, the cutting forces and vibration at the pocket corner with different HSM conditions are measured. The results show that the sharper pocket corner, higher cutting speeds, larger feed rate per tooth and radial depth of cut, will result in increasing of cutting forces and vibration amplitude. Thus, it will lead to be unstable during the process of high speed milling pocket corner.

A thermo-mechanical numerical model for high speed milling hardened SKD11steel is developed to study the influences of mechanical load and thermal load on residual stresses for each feed. The residual stresses are predicted, which are induced by high speed milling hardened SKD11 steel. Based on a simplified two-dimension assumption, the continuous feed numerical model of high speed milling hardened SKD11 steel is developed. A modified Johnson–Cook (J-C) model considering the effect of phase transformation on flow stress is employed to model residual stresses. The results show that residual stresses dominate over the mechanical load and its impact becomes more and more significant for the posterior cut. The tensile surface residual stresses of posterior cut becomes larger than the previous cut but the work hardening thickness of posterior cut becomes thinner in the condition of this study.

At present, most of the researches on carbide surface modification are focused on the method of chemical vapor deposition and physical vapor deposition in order to enhance its wear resistance and surface hardness. In this paper, C2H2 and O2 of flame are used to deposit carbon coatings on YG 16 cemented carbide surface. The influence of deposition time have been investigated with the method of XRD, SEM. Carbon coatings structure, quality and Cross sectional microstructures of carbon coating was analyzed.The experimental result show that after different deposition time, the typical spherical diamond\nanometer carbon tube and diamond-graphite-no crystal carbon coatings have been formed on the surface of cemented carbide.