The Numerical Simulation Of Low Pressure Die Casting And Process Optimization Of Large Size Aluminum Alloy Wheel

Manufacturers of large size aluminum alloy wheel are becoming more and more, bywhich the method of using low pressure casting on abroad. However most of the large sizewheels are steel wheel using forging method due to the domestic production technology isrelatively backward. At present, the domestic manufacturers haven’t mastered the method ofadding water-cooling pipes in the low pressure casting mold to product large wheel. As theresult of the nonuniform casting section size and the longer solidification time, it was easy togenerate defects in the process of low pressure casting which is the significant advancingfront for the manufacturing science such as shrinkage and crack and so on. Computersimulation of casting process which is the cross science of many subjects, including materialsscience, numerical analysis, heat transfer and computer graphics, etc. Numerical simulation ofcasting processes can help engineers predict casting defects, assure the quality of casting,increase productivity and reduce the production cost.To solve the problem of shrinkage porosity generated in the hot section during theprocess of low pressure casting large aluminum alloy wheel, this paper analyzed thedistribution regulation of the temperature field during the process of filling and solidificationthrough the PROCAST software. It was concluded that the casting generated shrinkagedefects in the junction between rim and spokes from the simulation results.The simulationresults were coincided with the actual production. The cooling rate was improved by usingadding water-cooling pipes in the corresponding parts of mould and the shrinkage porosity inhot section was effectively reduced. While the mechanical properties of each part wereunqualified and metallographic crystalline grains were coarse. This paper adopted the methodof adding water circle in the other parts of the mould to obtain better crystalline grains andmechanical properties. The water cooling pipe location, size, open time and duration of waterwere determined according to the results of numerical simulation. This method is contributedto accelerating the cooling rate of castings, getting more fine metallographic crystalline grain size and making the actual production of castings meet the requirement of the mechanicalproperties. The results showed that the optimized process not only improved the performanceof casting but also reduced the production cycle and improved the production efficiency.