The Effect Of Magnetic Field On Suspension Refining

Electromagnetic levitation has many advantages,including no pollution from container wall,even melt surface,fast heating melting,and quick balance of the surface of gas-liquid phase.It can be used to develop high purity materials,such as refined metals,semiconductors that can remove impurities,and so on.However,since the research reports in the levitation refining are limited,the study of levitation refining technology can help enrich the electric theory of maglev technology in China.With a method that combines the experiment,the theory,and the simulation,this research explores the area of levitated refining magnetic field,studies the levitation principle of magnetic field,establishes mathematical model,applies computer simulation and verification,and finally concludes the best parameters for the further experiment research.The main research results are as following:(1)This research has established a computer simulation of suspended magnetic field and has calculated and validated the model.On this basis,the research has also conducted stimulated calculation of influence of different magnetic field frequency and current on suspension.By computer simulation,the research has uncovered the relation between the distribution and the size of the magnetic field and different frequency and current.The study found that the suspension effect is better when the suspension sample quality is about 1 g,frequency is around 280 kHz,and the current is about 375 A.(2)The research conducted the influence of coil structure on the magnetic field of electromagnetic levitation refining.Also,the research established the computer simulation model,uncovered the influence of coil number of turns on the magnetic field,and concluded the appropriate coil parameter selection.The study found that the suspension stability is better when the stable coil is 2 turns and suspended coil is 3 turns.(3)The research conducted the influence of the magnetic field on temperature field under electromagnetic levitation refining.The research has also built the coupling model of magnetic field and temperature field.The study uncovered that the magnetic field where the specimens are changes corresponding to the shape of specimens.The range of the temperature of the temperature field where the specimens are does not vary a lot.The temperature is even because the joule heat generated in the sample within the electromagnetic stirring.(4)The research conducted the experiments on the electromagnetic levitation refining.The applied stimulation conducted the best parameters including current,frequency,coil parameters,and temperature.By using ferrosilicon alloy and stainless steel as sample,the research also has conducted a levitation refining experiment gotten good results.The effect of phosphorus removal by the specimens of ferrosilicon alloy is remarkable,which can remove about 41%(mass percent)of phosphorus.The specimens of the stainless steel have gotten a good results when carbon dioxide,instead of oxygen,decarburized.At the same time,the sulfur elements has decreased and avoided significant loss of chromium.