PROCESS AND APPARATUS FOR THE ELECTROMAGNETIC CASTING OF METALS AND NON-MAGNETIC SCREEN FOR USE THEREIN

摘要

An electromagnetic casting process and apparatus is described and claimed for electromagnetically casting ingots having at least one corner or region of small curvature, e.g. rectangular ingots, in which means are provided which locally reduce the magnitude of the electromagnetic force field used to shape the ingot in the region of the corners so that metal flow into the corners is promoted. The localised reduction of electromagnetic force field is obtained either by using a non-magnetic screen (32) which provides increased screening in the corner regions of the ingot or by shaping the inductor (11) to provide a greater air gap between the inductor and the ingot in those corner regions. Optionally cooling fluid is applied asymmetrically to the ingot surface so that the solid-liquid interface (25) is locally lowered in the corner regions. Non-magnetic screens which provide increased screening and localised reduction of the force field in the corner regions of the ingot are also claimed.