| As the purpose of this research, a suit of continuous stirring unit with three induction coils working together will be designed, And then, the processing parameters of the three coils will be selected and optimized to obtain the suitable semi-solid slurry of ZL112Y alloy through the simulation of fluid field with computer, both saving energy sources and easy controlling the temperature are the precondition of this selection. Firstly, an electromagnetic stirring unit for experiment with a single coil was designed in this paper. A reasonable semi-solid temperature and stirring technology were confirmed through the comparison of the microstructure of the material at different temperatures and stirring technologies, That was 590℃of the temperature and 500A of the concussive current. With this technology and temperature, the global аphase distributed in the microstructure of alloy shapely, and the size ofаphase was 20μm. Secondly, the modeling and simulation of the coupling of the electromagnetic field and the fluid field of electromagnetic stirring with single coil were done, and then the distributing of the electromagnetic field and the fluid field were obtained through the simulation. Two equal swirls distributed in the melting area lengthways from the result of the simulation, and it was correct because it accorded with the principle and the experiment of the electromagnetic stirring. A average velocity of 3.2cm/s in the melting area was calculated at the condition of 590℃and 500A, and this velocity was considered as a criterion whether it can gain semi-solid slurry. Thirdly, a continuous stirring unit for experiment was designed, and two problem, the choice of the container of the melting alloy and the design of control valve of the pedestal, were solved. Fourthly, the modeling and simulation of the coupling of the electromagnetic field and the fluid field of the continuous course of electromagnetic stirring with three coils were done. The distributing of the fluid field in the melting area was obtained, and many swirls of flow in the area were found from the result. The range of the temperatures of the area from the bottom to the 32mm above it were 590℃to 594℃, because the temperature in this area below the temperature line of the liquid of this alloy, so solid phase appeared in this area. In addition, a big swirl of flow existed in this area from the result of the simulation, it was considered that almost all solid phase moved in the swirl of this area, and circumvolve of pure liquid existed in other area. Three different stirring technologies were used in the simulation, and the average velocities at the exit of bottom of the melting alloy with the two technologies, 500A-800A-100A and 400A-600A-800A, were 6.3cm/s and 4.1cm/s respectively, both exceed the velocity of 3.2cm/s. However, the average velocity at the exit of the melting area with third technologies (200A-400A-600A) was 2.45cm/s. So the reasonable semi-solid slurry could be obtained with the first and the second technologies. Obviously, the second one was better than the first one because it saving the energy resources. At last, the second technology was mended to 400A-600A-400A, and the average velocity was 3.9cm/s, it was comparatively perfect, and there was a meaning of positive guidance to the experimental research of the continuous electromagnetic stirring.
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