The microstructure of AI-Ni alloy has a significant influence on its performance, while electromagnetic stirring is one of the most effective methods for control of solidification structure of AI alloy. To investigate the effect of electromagnetic stirring on the solidification of the ingot, the solidification of the Al-50Ni alloy in vacuum with electromagnetic stirring was described by numerical simulation in this paper; and a three dimensional mathematical model was established. The electromagnetic field was simulated by ANSYS software and the thermal-flow field was simulated by FLUENT software. The coupling between the electromagnetic field and the thermal-flow field was implemented by user-defined subroutines. It is found that the current intensity has significant influences on the fluid flow and the microstructure of the alloy. The simulation results agree well with the experimental results, and the optimum current intensity under the exprimental conditions is 80 A, while the frequency is 50 Hz.
A transient,two-dimensional,coupled finite element model was employed to simulate the solidification and shrinkage of continuous casting steels by means of ANSYSTM.In the model,a gap-dependent heat transfer condition was introduced to modify the heat flux function,and the variations of material thermal properties,mechanical properties as well as the yield function with temperature were considered.The solidification and shrinkage processes of four round billets and two square billets were simulated by indirect coupled method.Simulation results show that carbon content,pouring temperature,casting speed and shape of billets have distinct influence on the solidification shrinkage of billets.Ideal continuous parabolic tapers were designed and optimized according to the calculated shrinkage curves of billets.
Wang TongminCai ShaowuLi JunXu JingjingChen ZongningZhu JingCao ZhiqiangLi Tingju
