Abstract: A method for producing a composite wire for addition of solid products to metal baths in which the core comprises the addition products and a sheath of plastic material covers the core. The wire is produced by a coextrusion of the core and the sheath. The core comprises a mixture of a powder of addition product and a thermoplastic polymer powder, while the sheath comprises a thermoplastic polymer powder which can be the same as the thermoplastic of the core.

Abstract: Abrasive and/or refractory products comprising at least one compound from the group of oxynitrides of one or more metals or metalloids (such as Al, Mg, alkaline earth metals, Si, Ti or Zr) and obtained by melting and solidification.

Abstract: A method of producing heavy metal carbides of high specific surface area characterized in that a compound in the gazeous state of said heavy metal is caused to react with reactive carbon having a specific surface area at least equal to 200 m.sup.2. g.sup.-1 at a temperature comprised between 900.degree. and 1400.degree. C., and thus obtained carbides.

Abstract: The invention relates to a process for refining crude magnesium, and, in particular, the magnesium obtained by reducing the magnesium ore using iron-silicon.The process consists in treating the liquid magnesium with a metallic sulphide such as iron monosulphide, iron bisulphide or molybdenum bisulphide.The sulphides are contacted with the metallic bath which is agitated to promote the liquid-solid reactions and the formation of insoluble products which precipitate.This contacting is followed by decantation of the insoluble products and their separation from the refined magnesium.The process permits a significant reduction in the contents of calcium and silicon.

Abstract: Product for desulfurization of liquid cast iron composed of technical calcium carbide powder, to which may be added products intended to cause gaseous release in the bath and to modify the composition of the slag and which is coated or agglomerated either by resins or an organic compound having a clear-cut melting point and which is solid at ambient temperature. The process comprises mixing of the carbide and additives with the binding agent, resin, or organic product, agglomeration by pellet formation, compression or extrusion, and possible second grinding and sifting to obtain the desired granulometry. The product is added to the liquid cast iron using a lance, by gravity, or as a filled wire. It has good pourability, increased effectiveness, and reduced reactivity to moisture. It is used for desulfurization of both forge and foundry pig iron.

Abstract: A process for refining calcium containing aluminum as an impurity in the form CaAl.sub.2. The calcium is nitrided to form Ca.sub.3 N.sub.2, and that Ca.sub.3 N.sub.2 is made to react with CaAl.sub.2 initially present and with the particulate aluminum in such a manner as to form calcium, which is isolatable in the form of high-purity calcium containing less than 0.1% by weight of aluminum, and aluminum nitride.

Abstract: A process for forming cast, magnesium based alloy articles having reduced microshrinkage comprising the steps of forming a molten alloy consisting essentially of magnesium together with 4 to 10% by weight aluminum, 0 to 1% by weight manganese, and either 0 to 3% by weight zinc or 0 to 1% by weight silicon, adding to the molten alloy 0.01 to 2% by weight strontium, and molding the molten alloy and solidifying to form a cast alloy article.

Abstract: A porous refractory carbide with a large specific surface area is disclosed. The refractory carbide has a skeleton of metallic or metalloid refractory carbide and has a bimodal open porosity with a group of pores of 1 to 100 microns and a group of pores smaller than 0.1 micron.

Abstract: A magnesium-containing material for desulphurizing molten pig iron or steel having magnesium particles as a substrate covered with an organic material, which in turn is covered with a refractory powder. The organic material is either a saturated aliphatic acid or an ester of a saturated aliphatic acid which is a solid at room temperature.

Abstract: The invention relates to a catalytic system and to a method of producing such a system.The catalytic system consists of a support on which the catalytically active product is deposited. The support has mechanical or physical properties which are of interest in terms of the required working conditions, but a poor specific surface area. The catalytically active product, a metallic carbide, is obtained by coating the support in a suspension of a reducible compound of the metal in a solution of an organic compound, carbonizing this compound, reducing the metallic compound and carburizing the metal. The carbide thus obtained has a high specific surface area.Preferably, the support consists of silicon carbide produced by carbonizing a paste containing silicon, carbon and an organic resin.The invention is applicable to any form of catalyst but in particular to the monolithic catalysts intended for treating exhaust gases.

Abstract: An alloy based on magnesium with a load at rupture of at least 290 MPa and an elongation at rupture of at least 5%, the alloy comprising by weight, 2 to 11% aluminum, 0 to 1% manganese, 0.1 to 6% strontium, various possible impurities, and the remainder magnesium. The alloy has a structure including a matrix of fine grains of magnesium of a mean size below 3 .mu.m reinforced by intermetallic compounds dispersed homogeneously at the grain boundairies and having a mean size less than 1 .mu.m, the structure remaining unchanged if kept for more than 24 hours at a temperature up to 300.degree. C.

Abstract: The invention relates to high mechanical strength magnesium alloys and to a process for producing these alloys by fast solidification and consolidation by drawing generally exceeding 400 or 500 MPa, an elongation at break of generally at least 5% and a chemical composition by weight within the following limits:______________________________________ Aluminium 2-11% Zinc 0-12% Manganese 0-1% Calcium 0.5-7% Rare Earths 0.1-4% ______________________________________with the main impurities and the residue being magnesium, their structure being constituted by grains with a mean size below 3 .mu.m and intermetallic compounds with a size below 2 .mu.m precipitated at the grain boundaries.

Abstract: The invention concerns a multiphase alumina-based material formed by a matrix of corundum in which microcrystalline phases of aluminium oxycarbide, aluminium oxynitride and aluminium oxycarbonitride are homogeneously dispersed. The combined carbon content is between 0.05 and 5% and the combined nitrogen content is from 0.05 to 5% by weight. The material can be produced by the controlled injection of carbon and nitrogen into a molten alumina bath. The material is used for abrasive products and refractory products with high levels of performance.

Abstract: Magnesium alloy having a breaking load of at least 290 MPa, more particularly at least 330 MPa, having the following composition by weight: Al 2-11%, Zn 0-12%, Mn 0-0.6%, Ca 0-7%, but with the presence of at least Zn and/or Ca, having a mean particle size less than 3 .mu.m, a homogeneous matrix reinforced with intermetallic compounds having a size less than 1 .mu.m precipitated at the grain boundaries, this structure remaining unchanged after storage at 200.degree. C. for 24 hours; and a process for producing it by rapid solidification and consolidation by extrusion at a temperature between 200.degree. and 350.degree. C.

Abstract: The invention is directed to a process for the production of fine grains of silicon carbide which are formed by an agglomerate of submicronic grains having a specific surface area that is at least 100 m.sup.2 .multidot.g.sup.-1, which are intended in particular to serve as a carrier for catalysts for petrochemistry, and for catalytic reactions at elevated temperature which can attain 1000.degree. C., the process comprising reacting vapors of silicon monoxide SiO on carbon, being characterized by: generating vapors of SiO in a first reaction zone by heating a mixture SiO.sub.2 +Si at a temperature of between 1100.degree. and 1400.degree. C., under a pressure of between 0.1 and 1.5 hPa; and, in a second reaction zone, contacting the SiO vapors with reactive carbon in the divided state with a specific surface area that is at least equal to 200 m.sup.2 .multidot.g.sup.-1 at a temperature of between 1100.degree. and 1400.degree. C.

Abstract: The invention relates to a process for the preparation of silicon carbide whiskers by the reaction, in a non-oxidizing atmosphere, at a temperature of at least 1300.degree. C., of a charge composed of a mixture of carbon black and a source of silicon oxide, in which process the carbon black has an oxidability rate (measured by heating in air for 30 minutes at 600.degree. C.) of at least 85%, the silicon oxide source has a grain size of less than 100 .mu.m and the rate of rise in temperature between 1300.degree. and 1600.degree. C. is less than 30.degree. C.min.sup.-1 per minute if a static atmosphere prevails and at most 25.degree. C.min.sup.-1 if gas percolated. A stage of from 5 min to 5 h at 1600.degree. C. is optionally carried out.The carbon is preferably introduced into the reaction mixture in an over-stoichiometric quantity relative to the silica.The excess carbon is removed at the end of the reaction by oxidation in air at about 600.degree. C.

Abstract: The invention relates to a device for continuous injection under low pressure of a powdered additive into a stream of molten metal.It comprises, in succession from top to bottom:a top compartment 5 for the admission of the molten metal,a treatment chamber 7 connected to the top compartment by a calibrated inlet orifice 8 and in which there opens, on the one hand, a tube 9 connected to a device for injection of powdered additive under gas pressure and, on the other hand, at least one conduit 11 for evacuation of gases, fumes and possible sullage,at least one buffer compartment 6 cooperating with a means for adjusting the discharge rate of the treated metal,a means for collecting the treated metal, for example a mould or a ladle.