Papers by Keyword: Auto Panel Die

Abstract: Mo-Cr alloy cast iron is the most important material often used to make auto panel dies. To study high-speed machining process of auto panel dies, the material’s elastic modulus and fracture critical values of Mo-Cr alloy iron at 20°C-800°C were studied based on the high temperature elongation test. The material’s stress-strain relation curves at various temperatures (20°C-500°C) and various strain-rates (500/s-5000/s) were studied and the dynamic tensile yield strength values were obtained by dynamic SHPB(Split Hopkinson Pressure Bar) high-speed compression test. The test observation showed that Mo-Cr alloy iron has heat resistance and its behavior is between toughness and brittleness materials. Its toughness is enhanced with temperature increasing. At 20°C-500°C and strain-rates (500/s-5000/s) the dynamic tensile yield strength is decreased about 17％-24％ by temperature softening effect and is increased about 56％-70％ by strain-rate strengthening effect. The strain-rate strengthening effect prevails over temperature softening effect. Keywords: Auto panel die; Mo-Cr alloy cast iron; SHPB; Temperature softening effect; Strain-rate strengthening effect

Abstract: On the base of analyzing material constitutive model, chip-tool contact friction, and chip separation and fracture, a finite element model (FEM) was built to study the high-speed machining process of alloy cast-iron. The shaping process of serrated chip in high-speed milling alloy cast-iron was simulated and analyzed in detail. It was shown that machining parameters affect the serrated chip forming greatly. The model can be used to optimize machining parameters, prolong tool life and improve machining surface quality.

Abstract: A finite element model (FEM) of high-speed cutting was built to study the mechanism of high-speed machining of alloy cast iron used widely in auto panel dies. The mechanics properties of workpiece material were obtained in the conditions of high strain-rate, high temperature and high strain through high-speed impact compress experiments. Several key technologies are studied such as friction and chip-tool heat conduction. The cutting temperature, stress distribution, and the chip formation process in the process of high-speed cutting alloy cast iron were analyzed based on the finite element model, which was validated through cutting force experiments. It shows that the FEM can simulate the high-speed cutting process of alloy cast iron materials.