Research On The Key Problems Of The Industrial Electromagnetic Soft-Contact Mold

Baoshan Iron & Steel Group Company and Northeastern University have cooperated in the research of Electromagnetic Processing of Material (EPM) since 1999. Soft-contact electromagnetic continuous casting is one of the main projects for the cooperation. And now it has been progressed into the phase of industrial scale test. This study mainly focused on the development of the industrial electromagnetic soft-contact mold because of its importance for the industrial test. A Φ 178mm mold for round billet was used as a case study. It is a complex multi-objective problem of metallurgy, electromagnetic field, forces and temperature for developing an industrial electromagnetic soft-contact mold. Therefore, the industrial electromagnetic soft-contact mold can be developed only when various coupled physical phenomena, which occur in the mold, have been identified.In this paper, for the first time, the differences between the transient and averaged electromagnetic forces in the direction and its effect on the electromagnetic soft-contact metallurgical behaviors were revealed by means of the equivalent circuit model and Lentz law. An analytical solution of the meniscus behavior under the action of an electromagnetic force based on Young-Laplace equation was also obtained firstly. Moreover, the variations of the traditional metallurgical behaviors, such as the dynamic pressure in the flux channel due to the mold oscillation under the influence of electromagnetic forces, and the corresponding mechanism of obtaining soft-contact electromagnetic continuous casting metallurgical effects, were also studied using analytical methods. Based on extensive theoretical investigation, some simple but reasonable and feasible guidelines were developed, which can be used for the investigation of the industrial soft-contact electromagnetic mold, including the structure design of the mold, the selection of the mold structural parameters. Based on extensive theoretical investigation, the meniscus height and shape are considered as the key object variables, magnetic flux density as the process variable and structural and electromagnetic parameters as the source variables, although the parameters for developing an industrial mold are numerous and complicated. This theoretical investigation makes subsequent research well layered.