Electromagnetic confinement and shaping for a plate form part

摘要

The relationship between the melt shape, the electromagnetic pressure and the magnetic field is studied for the electromagnetic confinement and shaping of a plate-form part. The results of experimental observation and theoretical inference can be summarized as follows. If the melt thickness a is sufficiently large, providing a ratio of plate thickness to current theoretical skin depth, a/δ>2.2, the electromagnetic pressure acting on the melt can be expressed simply as P{sub}m=B{sup}2/2μ, and the melt shape can be known just by measuring the distribution of the magnetic flux density. If a is small and makes the ratio a/δ<2.2, the melt shape and the electromagnetic pressure for confining and shaping are determined not only by the magnetic flux density B, but also by the melt thickness a, the electromagnetic parameter μγ and the current frequency f. In this paper, an equation for calculating the electromagnetic pressure acting on a "thin plate-form melt" is proposed. The equation gives the precise relationship between the electromagnetic pressure factor p and the melt thickness a, the electromagnetic parameter μγ and the current frequency f.