Study On Two Wheel Spinning Process Producing A356 Aluminum Alloy Hub Stock Prepared By Die Casting With Water Cooling

The application of aluminum alloy hub is of great significance to the lightweight of automobiles.A356 aluminum alloy has become a common material for aluminum alloy hub due to its high strength,excellent corrosion resistance and good fluidity.At present,the main production technology of A356 aluminum alloy hub is casting-spinning process.A large number of scholars have conducted research on A356 aluminum alloy hub,but the related research mainly focuses on three wheel spinning process of forming A356 aluminum alloy hub and the hub stock is prepared by die-casting with compressed air-cooling.However,there is few research on the two wheel spinning processes of the hub and the hub stock prepared by die casting with water-cooling.The microstructure of A356 alloy prepared by die casting with water-cooling is finer and have fewer defects and better mechanical properties.The two wheel spinning process can improve the production efficiency and reduce the production cost,besides the reduction of each wheel in two wheel spinning process is larger than that in three wheel spinning process.Therefore,it is of great theoretical significance and application value to investigate the two wheel spinning process producing A356 aluminum alloy hub stock prepared by die casting with water-cooling.In this thesis,the hot deformation behavior of A356 alloy prepared by die casting with water-cooling was studied by Gleeble-3500 thermal simulation test machine.The stress strain curve of the material was obtained,the constitutive equation and hot working map were constructed and the processing parameters of deformation temperature of 340??380?and the strain rate of 1s^-1?10s^-1were obtained.After determining the spinning process parameters,the MSC.Marc software was used to simulate the spinning process of A356 aluminum alloy hub.The influence of hub stock with different height diameter ratio on spinning forming was analyzed by using the three wheel spinning process parameters from the enterprise.The results show that the hub stock with height diameter ratio of 3.6 has better forming effect.Subsequently,the two wheel spinning process was used to analyze the equivalent stress and strain of the hub stock with a height-to-diameter ratio of 3.6 during the spinning forming.The results showed that the equivalent strain of the two-wheel spinning hub is larger and the equivalent stain distribution along radial was deeper than that of the three-wheel spinning hub.According to the two wheel spinning process,the influence of the process parameters such as reduction percentage of wheel,fillet radius of wheel and spindle speed on the forming quality is analyzed by using the single variable method,The optimized process parameters of the two-wheel spinning process were obtained:Reduction percentage of 40%for No.1 wheel,fillet radius of 13mm for No.1 wheel,wheel feed ratio of 1.2mm/r,spindle speed of 450r/min,spinning temperature of 360°C,friction coefficient of 0.1.The spinning experiment was carried out by using the two wheel spinning process and optimal process parameters.The hub microstructure was observed and the mechanical properties was tested.The results show that the two-wheel spinning hub has more uniform microstructure along the hub thickness,and the better mechanical properties than those of the three-wheel spinning hub.