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Compared to traditional steel wheels,aluminum alloy wheel hub has some merits as light weight,good heat dissipation,well comfort,fuel savings,aesthetic appearance etc,so that it has been widely used.Low pressure die casting is one of the main method of producting aluminum alloy wheels,which is a near non-casting margin founding technics.Compared to traditional casting,low pressure die casting has obvious advantages,and it is one of the developmental direction of casting.This papper is according to the existing problems in the process of a particular model aluminum alloy wheels’ production,such as shrinkage cavity and porosity.This papper is based on the study of thethemral-delivering and finite element theory,by using of Pro/e for entity modeling and die design,then by using of ANSYS for the numerical simulation of casting solidification process.Finally,by the way of the orthogonal experiment to optimize the process of die.According to thethemral-delivering theoy,the temperature and internal energy of the system are significantly variant during the casting solidification process.Considering the latent heat of solidification,the thermal alnalysis about casting solidification process of the aluminum cylinder heat isnon-linear and trnasient. At the same time,according to the process’s finite element characteristics,finite element solution of the nonlinear transient temperature field has been carried out.In this paper,using the method of combining CAD software Pro/e and CAE software ANSYS,that is using Pro/e to set up solid model and using ANSYS for mesh division and the finite element model’s setting up,as well as the numerical simulation’s carrying out.In calculations,considerring accuracy and computational efficiency,appropriate treatment has been taken to simplify the model.Nonlinear transient temperature field analysis and computer simulation have been carried out with ANSYS’s thermal analysis function.The results showed that ’isolated island defects’ was founed in the middle of wheel rim and the spokes,and it coincide with the actual production.With the method of orthogonal experiment to optimize the tooling process,choose the the four larger impact factors of molding casting process as fllow:the cooling water’s flow rate in lateral die,upper die and lower die,as well as the lateral die’s temperature,each factor have three levels of organization.Finally,get the best optimization program as follows:the cooling water flow rate of lateral die,upper die and lower die are 0.5m/s,1m/s,1m/s,at the same time adjust the initial temperature of lateral die from 300℃to 200℃.Simulation result showed that this method can improve the quality of casting and production efficiency,as well as lengthen the life of die.
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