Numerical Simulation Of The Semi-solid Magnesium Alloy Twin-roll Casting Process Based On Thermal Coupling

The semi-solid molding technology which emerged in the 1970's is a near net molding technology. Because it has many advantages including good density of the molded part, excellent mechanical properties, long life of die, creating a more complex structure, environmental protection, high efficiency and energy saving, more and more attention is given by various countries and it is considered to be one of the metal molding technology which has most development potential in the twenty-first century. Magnesium alloys have advantages of lower density, higher specific strength, high stiffness, good dimensional stability and good electromagnetic shielding effect, therefore it become the lightweight materials of the aerospace, automotive, electronics and other heavy industries in recent years. The semi-solid molding technology has very broad application prospects and the research on the rheological molding process of the semi-solid magnesium alloy is very less, so the numerical simulation on continuous casting rheological molding of the semi-solid magnesium alloy in this paper has very important significance.In this paper, the flow field and temperature field are simulated based on the existing temperature field model of the roll casting process, so as to provide the flow field and temperature field data for the finite element numerical simulation of the thermal– mechanical continuous casting process. The stress– strain field mathematical model which can describe the rheological behavior of the material in the continuous casting process is built. The viscoplastic finite element method and elastic-plastic finite element method are used on the deformation area and the solidification area separately. The mathematical model is discreted and solved by the finite element analysis software, then the mathematical model of thermal-mechanical coupling is established.Therefore, the following aspects are researched in this paper. (1) Establish flow-thermal control equation and energy equation, then consider the whole coupling; (2) Establish thermal stress control equation on the basis of the whole coupling; (3) Process some main parameters; (4) Rationalize the boundary condition of the whole coupling equation; (5) Use the ANSYS software to do the numerical simulation of the flow field, the temperature field and the stress field. In this paper, the computing results are comparatively analyzed and some reasonable proposals are given. It provides some reference for the industrial production of the twin-roll casting technology of the magnesium ribbon billet in the future.