| Electromagnetic driving and controlling (EM-D&C) molten metal is one of most important key technique of electromagnetic processing of materials (EPM). Study of EM-D&C not onlyimproves solidification quality, expand5 equiaxed zone, and eliminate gas. macrosegregationand non-metallic inclusion, but also innovatertontinuous casting operation. Ago reseseach oftenemphasize1 particularly on single aspect: electromagnetic driving (electromagnetic stirring) or electromagnetic controlling (electromagnetic brake, electromagnetic forming, electromagnetic levitation etc), EM-D&C combine5 these two functions, which embody electromagnetic technique more designing-ability and make EPM more high-technological ingredient and improve quality and efficiency of continuous casting.Technique of EM-D&C is paid more and more attention by national science and research ministries. The author fortunately participate in funds by National Major Scientific Project "Study on shape controlling of molten metal and solidification fundamental under electromagnetic field", and Fundamental Research Foundation "Effect of electromagnetic force on refining, homogenizing and purifying of continuous casting slab", and "Trans-century Talent" Foundation "electromagnetic shape controlling and processing of materials" and Bao-steel Project etc, on which I finished my dissertation.Base on Maxwell electromagnetic theory, two magnetic moving modality styles of two phase-two-pairs-of-pole and three-phase-three-pairs-of-pole electromagnetic driving devices are analyzed by numerical simulation and experiments analysis, parameters of frequency, shape and dimension of yoke are optimized. The aim of above research is to develop energy-saving and high-effective electromagnetic driving equipment.Rules of molten metal surface moving are studied by the method of laser sensor measuring displacement: (1) Intermitted electromagnetic field with commercial frequency is devised, and relatively proportion electrical source is developed. Wave characteristic on molten metal surface generated by rotating electromagnetic field is analyzed. Relationships intermitted frequency, on and off timing with surface wave are reviewed. Response rules between intermitted frequency and velocity field are researched. (2) It is of great directing signification for continuous casting operation to understand shape and wave of meniscus, and which is inspected on real time by laser sensor. It establishes foundation that quantitatively and real-time inspecting relationship between electromagnetic force with shape and wave of-III-Abstractmeniscus.Magnetic force excited by moving magnetic field media with permanent magnet breaks a new way of EPM. Two kinds of permanent magnet have been brought forward in this dissertation, one is permanent travelling magnetic field, and the other is double driving permanent rotating magnetic field.Permanent magnet travelling apparatus is developed. Analytic resolution of magnetic force excited by travelling magnetic field is analyzed, the expression of magnetic force Fx, Fy is deduced, and magnetic driving force from down to upside has been experimentally observed, that imposing travelling magnetic field on molten metal can refine and homogenizing solidification structure.Double driving and controlling apparatus media with permanent magnet is manufactured; reasonable regulating rotating velocity of upon and down driver can improve shape of meniscus, suppress surface wave, and stir molten metal. Meanwhile, uniform initial solidification shell and refine solidification structure is obtained.Mechanism of solidification when imposing electromagnetic driving force on the molten metal is studied by simulating solidification condition at final stage of continuous casting with low melting point alloy. By boundary layer and characteristic ratio of solidified phase, effect of electromagnetic driving force on temperature distribution and solidified velocity is analyzed. Experimental results show that it is very different solidified mechan...
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