1994 Volume 80 Issue 8 Pages 617-622
Suppression of wave motion of molten metal surface is one of the most important technology for controlling initial solidification in various casting process, e.g. continuous casting, twin roll casting, etc, where the suppression of wave motion can improve surface quality of cast metal. The wave motion is motivated by gravity force, so that the diminution of apparent gravity force by imposing vertical electromagnetic force must be successful for wave suppression.
In this paper, at first, based on this principle, frequency changes of wave motion were measured in two imposition types of both stationally magnetic field and direct electric current. In case current was parallel to the wave vector, the frequency did not change. On the other hand, in case magnetic field was parallel to the wave vector, the frequency did change according to the dispersion relation modyfied by apparent gravity force. Next, from the standpoint of the process control in actual applications, another experiment was conducted where the imposition area of electric current is limited to around meniscus. As the results, it was found that this technique for wave suppression is still effective for deep molten metal pool.
