Abstract: A process for melting an electroconductive material (1) in a melting furnace (10) by induction in a cold crucible includes electromagnetically confining a mass of the electroconductive material (1) up to its melting temperature. Then, at least one vortex is created in the liquid material to inclusion particles contained in the liquid electroconductive material. The vortex or vortices are created by electromagnetic stirring. A part of the mass of the liquid electroconductive material (1) is poured in a pouring tube (15) disposed under the melting furnace (10), subjecting the jet of the pouring of the liquid electroconductive material (1) to a radial electromagnetic confinement, and ensuring a vertical coaxial alignment of the electromagnetic fields acting on the mass of liquid electroconductive material (1) and on the pouring jet of the mass. An induction melting furnace employing a cold crucible for carrying out this is also disclosed.

Abstract: The invention provides a steel containing by weight 23% .ltoreq.Cr.ltoreq.28%; 15%.ltoreq.Ni.ltoreq.28%; 0.5%.ltoreq.Mn.ltoreq.6%; 3%.ltoreq.Mo.ltoreq.8%; 0.35%.ltoreq.N.ltoreq.0.8%; and 1%.ltoreq.W.ltoreq.5%. The steel has a high resistance to corrosion and may be used for manufacturing massive parts for any application, in particular for manufacturing equipment for oil platforms and chemical works, containers for transporting corrosive products, ship hulls and ply sheets.

Abstract: A method for obtaining a product from pre-alloyed powders in which the powders are subjected to compaction treatment. The powders are first subjected to pre-treatment under low pressure (or without pressure) at a temperature such that segregating materials precipitate out in stable phases.

Abstract: Superalloy with a nickel base matrix having good mechanical properties when ot in respect of tensile strength, creep resistance, low cycle fatigue and resistance to crack-propagation of which the composition in percentages by weight is as follows: Cr 11 to 13; Co 8 to 17; Mo 6 to 8; Nb less than or equal to 1.5; Ti 4 to 5; Al 4 to 5; Hf less than or equal to 1; C, B, Zr each less than or equal to 500 ppm; Ni remainder to 100. The alloy can be manufactured advantageously by powder metallurgy techniques and used in the manufacture of turbo machine disks.