Simulation Of Heat Pipe Technologe Application In Foundry Of Aluminum Alloy Motorcycle Wheel

Heat pipe is a high thermal transfer component, its thermal conductivity can be 100～1000 times of the good metal conductor. Presently, heat pipe is widely used in space technology, electronics appliance, energy power, chemical industry, light industry, metallurgy and so on.Aluminum alloy motorcycle wheel is investigated in this paper. Gravity casting with metal mould is the principal method to produce this part. Shrinkages and dispersed shrinkage are the main defects. The method to prevent the defects is to set the riser at the hot spot and use cooling water. The overall yield of casting is about 50%. The process of low pressure casting with cooling water is designed to produce this part without the riser. The riser is a waste of metal under the condition of gravity casting, and the low pressure casting with cooling water is inconvenience in structures and short life-span. Consequently, the method of using heat pipe instead of riser and cooling water is put forward.The 3-D solid models of aluminum alloy motorcycle wheel and mould were built by Pro/ENGINEER software. The model of finite element (FE) was created by ProCAST software. Before calculation, the boundary conditions and initial conditions for the case of gravity casting or low pressure casting must be set up. The process of filling of mold cavity and solidification of the part were simulated. From the results of the simulation, the area of shrinkage defects is obtained. The defects were mainly located on the riser under the condition of gravity casting, whereas on the hot spot in which wheel rib and collar rim intersect under the condition of low pressure casting. The area of mould to be cooled is obtained from the simulation.The structure of the heat pipe and fixing location in the mould were designed according to above the results of simulation. And the job temperature and the thickness of the pipe were confirmed. The working media in heat pipe also was chosen. The equivalent heat transfer efficient is obtained from the calculation of the heat resistance, then check the wall thickness of heat pipe. It is proved that the heat pipe can cool the mould and control the cooling order.The process of filling of mold cavity and solidification of the part were simulated for the case of gravity casting and low pressure casting using ProCAST software. Through observation of solidification process, change of temperature, shrinkage and dispersed shrinkage, it is indicated that directional solidification is a main solidification mode for this part, and the castings have no defects.Theoretical calculation and computer simulation prove that heat pipe used in casting of aluminum alloy motorcycle wheel can eliminate the shrinkage defects of castings.