Experimental Study on Mould Oscillation-less Continuous Casting Process under High Frequency Amplitude-modulated Magnetic Field

Abstract

In order to investigate the influence of high frequency magnetic fields on surface quality of billets in the soft-contacted electromagnetic continuous casting, several kinds of high frequency Amplitude-Modulated Magnetic Field (AMMF), that is, rectangle, triangle and sine wave AMMF, were adopted in this experimental research. The magnetic field flux in the mould and the intermittent contacting distance were measured. The experiments of Mould Oscillation-Less Electromagnetic Continuous Casting (MOLECC) of tin under the three wave kinds of AMMF were carried out. It is shown that: (1) During the MOLECC process under the rectangle, triangle and sine wave AMMF, when the modulated wave frequency is a little lower than the intrinsic frequency of the experimental system the intermittent contacting distance is the greatest, the mould flux lubrication is the best, the continuous casting withdrawing resistance is the least and the surface quality of billets is the best. (2) Among the three kinds of AMMF, sine wave is the best in deducing the withdrawing resistance and improving the billets surface quality.

A Periodically Reversed Flow Driven by a Modulated Traveling Magnetic Field: Part I. Experiments with GaInSn

“…However, in the case of continuous casting of light or ferrous alloys, the magnetic field can be mainly divided into high-frequency and low-frequency magnetic field. The former is usually to improve superficial properties with the variation of electromagnetic pressure, [5,6] and the effect of Joule heat normally plays an essential role in such case; the purpose of the latter is often to stir the melt in order to remove inclusions, to control the grain structure and size, or to improve the homogeneity of temperature and composition.…”

Present Situation and Development Perspective of Soft-Contact Electromagnetic Continuous Casting Technology

“…The magnetic field introduce usually alternating magnetic field with amplitude constant frequency outside soft-contact mold, including the low frequency, medium-frequency and high-frequency. Some researchers quested for the continuous casting process under the other forms of electromagnetic field [10] , such as rectangles wave magnetic field including discontinuous frequency magnetic field and pulsed magnetic field, quasi-sine-wave magnetic field, semi-Triangular-wave magnetic field and compound magnetic field which are chiefly composed of high frequency magnetic field and rotating magnetic field or alternating magnetic field and static magnetic field. Based on the extension and promotion of the discontinuous magnetic field concept, people put forward amplitude-modulated magnetic field, this new method of magnetic fields imposed become a new start to explore magnetic field design under special requirements for continuous casting process.…”

Amplitude-modulated Magnetic Field Coupled with Mold Oscillation in Electromagnetic Continuous Casting

“…15) Tables 1 and 2 list the experimental parameters. The friction forces of continuous cating and oscillation marks depth on the billets were measured.…”