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Electromagnetic stirring technology refers to the electromagnetic field of liquid metal electromagnetic force applied to the process of controlling the flow of liquid to break, fuse dendrites, increasing the nucleation rate and thus improve the material microstructure and performance. Electromagnetic stirring technology in the steel industry has been widely used, but in the ferroalloy industry needs to carry out research. After cooling, manganese alloy casting easy to crack, it is difficult molding, manganese products in modern processing technology in multi-channel to go through complex processes, because of the fragility of manganese, manganese crushing process in chunks when accompanied by a 15% manganese powder produced , when recycled energy, does not meet the requirements of energy conservation. The manganese alloy in liquid and semi-solid state, applying mechanical vibration, pressure, electromagnetic stirring and other processes, can effectively change the structure and macroscopic ingot microstructure. Based on the structure and microstructure of the ingot comparison focuses on the following aspects. First, DC measuring instrument for soft magnetic materials manganese alloy carbon manganese, low carbon manganese, manganese magnetic parameters were measured, the measurement results show that the weak magnetic manganese alloys and materials with carbon saturation magnetic induction the increase and enhanced. Secondly, according to the electromagnetic theory, the establishment of a two-dimensional simulation model of a magnetic stirrer, and through Ansoft finite element analysis software to simulate the magnetic flux density within the model size and the magnetic field distribution. On this basis, analyzing two-dimensional model parameters on the magnetic flux density and magnetic field distribution of the size range of the degree of influence, derived electromagnetic stirrer main factors are: the frequency and current. Meanwhile, the use of home-made magnetic induction meter measured magnetic stirrer magnetic induction chamber that model simulation values ??consistent with the actual measured values. Finally, the number of ingot cracking, cracking temperature and other macroeconomic indicators and microstructure comparison shows: Mechanical vibrations can refine the grain, but not forming ingot; pressurized solidification in a certain extent, and changing the crystal grain refinement grain boundary shape, the basic shape of manganese alloys; manganese alloy melt solidification electromagnetic stirring only can refine the grain, grain boundary morphology change, and got spherical grains; manganese alloy in the mold until the liquid is about to enter, its liquid electromagnetic stirring, the electromagnetic force so soon solidified molten manganese alloy vortex motion, observe the ingot microstructure found that there has been partial spherical grain boundaries and a large circle, and the number of times the grain growth. Comprehensive comparison manganese alloy four kinds of granulated molding process shows that before the upcoming manganese alloy into a mold electromagnetic stirring of the melt process most practical feasibility. In this experiment the input current increases with stirring, stirring strengthened, manganese alloy grain structure is more compact; Power output frequency and electromagnetic stirring effective power exists an appropriate range. On carbon manganese and manganese alloys, stirring 50Hz frequency selection was better, low-carbon manganese alloys frequency at 30Hz appropriate. Theoretical analysis shows that the number of pole pairs fewer options energization coil, can increase the speed of the rotating magnetic field, the rotating magnetic field and the magnetic field lines can penetrate better into the cavity center, the pole pair number P = 1 时 appropriate.
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