Abstract: In a method of remelting metallic materials, particularly nickel-based superalloys, in which the melting operation is carried out in a cooled copper crucible under clean vacuum conditions by means of electromagnetic inductors, the magnetic field applied to the mass of molten metal has a frequency between 50 Hz and 5.times.10.sup.6 Hz, preferably between 5.times.10.sup.3 Hz and 5.times.10.sup.5 Hz, so as to effect simultaneously electromagnetic stirring of the liquid metal and a surface concentration at the cold walls of the mass to be recast of all the non-conductive particles, especially ceramic inclusions, thereby achieving an inclusion decanting.

Abstract: An electro-magnetic nozzle device for controlling the jet of liquid metal tapped at the outlet of a melting crucible comprises an electro-magnetic inductor and a magnetic field concentrator which surrounds the outlet of the crucible and is constituted by at least four three-dimensional sectors arranged evenly around the crucible outlet and separated from each other by radial slits, each sector having an internal water-cooled cavity, radially inner and outer walls of which the inner wall is of less height than the outer wall, and windings disposed in the inner and outer walls forming an electro-magnetic inductor.