Investigation On Technology Of Electromagnetic Continuous Casting Of Steel

Due to producing cast metals with high quality and benefiting to hot charge rolling and hot direct rolling, Electromagnetic Continuous Casting (ECC) is regarded as a great revolution of material processing, and also a up-to-date casting technique in the 21st century. The writer took part in two great projects: one is "Fundamental Research on Shape and Solidification of Molten Metal by Imposing Electromagnetic Field" supported by the Foundation of National Nature and Science of China, and the other is "the Effect of Electromagnetic Field on Refinement, Homogeneity and Pureness of Continuously Cast Steel Metal" supported by the National Science and Technology Ministry of China. The doctoral dissertation was finished on basis of the above research work. Main research results are as the following:The electromagnetic shaping system is the key apparatus to Electromagnetic Continuous Casting. Till now, there isn't systematic theory that can be found about the design of its structure and shape. Firstly, mathematical mode! of the system of electromagnetic shaping system was established. Then the effects of input current, current frequency, mold structure, inductor structure, and relative position between the inductor, pouring level and mold on the magnetic field distribution were investigated by means of numerical calculation and experiments. Finally electromagnetic mold with optimum structure and optimum magnetic field distribution was obtained. In a word, the results provided theoretic criterion for shaping technique of electromagnetic continuous casting.Meniscus motion has great effects on quality of continuously cast metals. Behaviors of Meniscus motion were studied under the conditions of multi-electromagnetic field by using Wood Alloy with low melting point. The experimental results showed that multi-electromagnetic field can controlmeniscus disturbance caused by electromagnetic stirring efficiently; as power and frequency of generator are changed, meniscus contour can be controlled optionally.Experiments results show that surface defects such as oscillation mark are eliminated by imposing high electromagnetic field, however, solidification structure of ingot cast is made up of coarse columnar grains. In order to obtain cast metals with high quality, electromagnetic continuous casting with multi-electromagnetic field was developed. Internal and external quality of continuously cast metals can be improved greatly by using the method, and it has been applied for patent.Lab caster for electromagnetic continuous casting was designed and made proportionally on basis of small-scale caster, and casting experiments using middle carbon (0.06%) were carried out. Steel billet with size of 100 x 100 was cast successfully for the first time at home. Both internal quality and external quality of the steel billet are improved more highly compared with qualities of castings produced by conventional continuous casting. Technique equipment and key parameters on electromagnetic continuous casting process are gained.