Abstract: The invention concerns a method for preparing a magnetic material by forging, characterised in that, in a first embodiment, it comprises the following steps; placing in a sheath an alloy based on at least one rare earth, at least one transition metal and at least one other element selected among boron and carbon; bringing the whole alloy to a temperature not less than 500° C.; forging the whole at a deformation speed of the material not less than 8 s−1. After forging, it is possible to subject the resulting product to at least one annealing and hydridation then dehydridation, in another embodiment, it consists in starting with an alloy based on at least one rare earth and one transition metal and proceeding as in the first embodiment. After forging and, optionally, annealing, hydridation and dehydridation treatments, the resulting material is subjected to nitriding.

Abstract: Method for obtaining a solid, magnetically anisotropic material, includes the steps of heating an alloy containing a rare earth element and at least one transition metal to a temperature higher than the melting temperature of the alloy and sufficient that alloy is completely liquid, and cooling the melted alloy at a rate at least equal to natural cooling in the presence of a continuous, static magnetic field to solidify the alloy and obtain the magnetically isotropic material.

Abstract: There is disclosed a process for optimizing the magnetic properties of a multiphase product of composition rare earth/iron/boron endowed with permanent magnet properties at ambient temperature. This composition serves as a precursor, which is first subjected to a decrepitation treatment by hydrogenation under low pressure at low temperature to obtain an intermediate hydride in pulverulent form. The pulverulent intermediate hydride is subsequently subjected to a first heat treatment under vacuum for partial dehydrogenation at a temperature below its element separation temperature. The non-separated product thereby obtained is subjected to a second heat post-treatment under an initial primary vacuum and extensively dehydrogenated until the primary vacuum is reestablished at a temperature close to 600.degree. C. The precursor can be an isotropic material obtained by fast quenching, such as wheel quenching or hot welding with a forging ratio of at least 10.

Abstract: Method for the preparation of permanent magnets at room temperature from an alloy containing at least a mixture of iron (Fe), boron (B) and rare earths (RE) including Yttrium, and for which there is a temperature range wherein said alloy is in two phases; one solid and brittle and the other one liquid. The method comprises heating said alloy under controlled atmosphere at a temperature sufficient to reach said temperature range, treating said alloy, and finally, optionally, allowing the treated alloy to cool. The method being characterized on the one hand in that said Fe-B-Re alloy is in a massive form, and on the other hand, in that the treatment of said massive alloy is carried out by welding of the magnetic solid phase Fe-B-Re.

Abstract: Phosphates, e.g., the polyphosphates and halophosphates, are prepared in high purity by melt thermocondensing corresponding precursors thereof, e.g., salts of orthophosphoric, pyrophosphoric or metaphosphoric acid, via electromagnetic induction heating, for example in an auto-crucible furnace.

Abstract: An induction furnace for melting refractory materials into a molten state by induction from a high frequency alternating current source. The furnace comprises a material holding crucible formed by a substantially cylindrical side wall having a single cylindrical turn. The side wall terminates in end portions which are spaced apart from each other to define a slot therebetween which extends generally longitudinally of the cylindrical wall. The side wall portions are connected to the source of alternating current so that the side wall turn comprises both the crucible and an inductor. An electrically conductive, elongated cooled member is mounted in the slot in spaced relation between each of the end portions. The elongated member is electrically insulated from the end portions to increase the breakdown voltage between the end portions.

Abstract: A method and device are provided for producing refractory materials by induction, in which process a mixture of material powders and a binder in solution in water are compacted by extrusion so as to form a solid bar. The bar is introduced into a cold crucible and is caused to melt by magnetic induction. The molten material flows through a lower orifice of the crucible. The invention applies more particularly to the melting of tungsten carbide.

Abstract: Process for the production of ceramic materials by high frequency induction melting.The powder containing the various components of the material to be prepared is introduced in a continuous manner into an aperiodic high frequency electric furnace, whose single flat coil serves both as the induction system and the cold crucible, the molten material also being continuously removed from the furnace in a chute passing through the coil.