High Temperature Deformation Behavior And Numerical Simulation On Precision Die Forging For Scroll Of 4032 Aluminum Alloy

Recently, with the development of automotive industry, the energy and the environmental problems become increasingly outstanding. With the increasing requests of people on the vehicle comfort, reliability and safety, the global auto manufacturers make efforts to improve the automotive structural design and look for new lighter materials to reduce vehicle weight. With a series of good performance, aluminum alloy is thought to be the optimum material to achieve automotive lightweight. High silicon aluminum alloy is used in manufacturing automotive engine piston, cylinder body and air condition compressor due to its low expansion coefficient, high hardness and high wearing resistance. Isothermal compression tests of 4032 aluminum alloy were performed on Gleeble-1500 thermal simulator. Regression analysis, optical microscope(OM) and transmission electron microscope(TEM) were employed to analyze the deformation behaviors and the microstructural evolution compressed at different deformation conditions.The morphologies of silicon in aluminum alloy were analyzed by OM at different deformation conditions. The results show that deformation temperature and strain rate have great influences on the silicon features. With the increase of deformation temperature, the silicon particles become rare and grow up gradually; silicon particles decrease with the increase of deformation degree. Transmission electron microscope was used to analyze recrystallized grain,dislocation and sub-grain. The dislocation density decreases with the increase of deformation temperature, while it increases with the increase of strain rate. The mean sub-grain size increases with the increase of deformation temperature and the decrease of strain rate. The increase of deformation temperature and deformation degree and the decrease of strain rate all improves the occurrence of dynamic recrystallization.The structure and features of the scroll for vehicle air-condition compressor were analyzed. Metal flow law of flow control forming was studied with the FEM software Deform-3D. Distribution regularity of the extruded length and the flatness of scroll under different counterpressure was studied. Reasonable counterpressure range was achieved from the simulation results. Forming process under different counterpressure distance was simulated. The influences of counterpressure distance on the extruded length and the flatness of scroll were studied. Die stress and deformation were researched and the relationship between forming load and the maximum effective stress of die was achieved.