1993 年 79 巻 11 号 p. 1260-1265
Surface quality of continuously cast metal can be improved by imposing high frequency magnetic field from the outside of a mold. In order to analyze the mechanism of surface quality improvement, the surface wave motion on meniscus and the contacting behavior between the mold and melt were measured by a laser level meter and by an electrical circuit method, respectively. These measured data were analyzed by use of the Fourier analysis method. Molten tin was continuously cast under the condition imposing magnetic field from the outside of the mold and a mathematical model describing wave motion on meniscus was developed. It was found that the motion of melt is consisted of a surface wave and a transverse swing which provides the intermittently contacting between the meniscus and the mold, and the space of ripple marks on the surface of the cast metal is related to frequency of the transverse swing caused by imposition of magnetic field. Surface quality of the cast metal can be improved by decreasing the wave amplitude of meniscus.