In recent years, metallurgists have paid close attention to the application of the electromagnetic field in metallurgy. Taking advantage of the force and the heat generated by electromagnetic field, one can heat or stir or transmit the molten metals or even control the shape of the molten metal in casting without contacting it, which cannot be easily done by other ways. So, the join of the electromagnetic field with metallurgical process always leads to the birth of a new technology. For example, electromag...