Abstract: The present invention relates to a particulate inoculant for treating liquid cast-iron, comprising, on the one hand, support particles made of a fusible material in the liquid cast-iron, and on the other hand, surface particles made of a material that promotes the germination and the growth of graphite, disposed and distributed in a discontinuous manner at the surface of the support particles, the surface particles presenting a grain size distribution such that their diameter d50 is smaller than or equal to one-tenth of the diameter d50 of the support particles.

Abstract: The present invention relates to a particulate inoculant for treating liquid cast-iron, comprising, on the one hand, support particles made of a fusible material in the liquid cast-iron, and on the other hand, surface particles made of a material that promotes the germination and the growth of graphite, disposed and distributed in a discontinuous manner at the surface of the support particles, the surface particles presenting a grain size distribution such that their diameter d50 is smaller than or equal to one-tenth of the diameter d50 of the support particles.

Abstract: The present invention relates to an inoculant alloy for treating thick ferrosilicon-based cast-iron parts, containing between 0.005 and 3% by weight of Rare Earths, characterized in that it also contains between 0.2 and 2% by weight of Antimony.

Abstract: The invention concerns a powdery product, of the type known as dry spray, for protecting centrifuge casting molds of cast iron pipes, comprising the usual components for this type of use, as well as an adjuvant for improving the flowability characteristics of said product when it is being deposited and make them less dependent on its physical or physico-chemical characteristics. Said adjuvant can be in particular silicone oil, potassium siliconate or micro-silica of density less than 0.1 g/cm3, as well as a mixture in any proportions of one or more of those.

Abstract: A powder product for the protection of centrifugal casting molds for cast iron pipes includes an inoculating metal alloy and possibly mineral powders, and a strongly reducing metal that is volatile at the temperature of the liquid cast iron. The use of products according to the invention prevents accumulation of dirt on molds and improves the surface condition of the cast iron pipes.

Abstract: The invention relates to an inoculant mixture for the treatment of molten cast iron, comprising 5 to 75% by weight of a ferro-silicon alloy of type A where Si/Fe>2, containing 0.005 to 3% by weight of rare earths, 0.005 to 3% bismuth, lead and/or antimony and less than 3% calcium, with a ratio (Bi+Pb+Sb)/TR of between 0.9 and 2.2 and 25 to 95% of at least one alloy of type B, based on silicon or ferro-silicon such that Si/Fe>2, containing calcium to a level such that the total amount of calcium in the mixture is from 0.3 to 3%. The above mixtures have a good granulometric stability over time and provide an efficient inoculation of cast pieces, in particular of thin pieces.

Abstract: The invention relates to a powder product for protecting centrifugal casting molds of cast iron pipes, dry-projected onto a first wet-spray layer, comprising constituents common to dry-spray products with exception of CaSi alloys, as well as a wet-spray additive serving to ensure the adhesion to the pipe, during its removal from the mold, initially applied to the permanent mold. Said additive can be an alkali carbonate or alkali silicate, for example, sodium silicate in which the ratio of the wt. % of SiO2 to that of Na2O varies from 1 to 3, or anhydrous sodium metasilicate as well as a mixture consisting of one or more thereof in any proportions.

Abstract: The invention concerns a powdery product, of the type known as dry spray, for protecting centrifuge casting molds of cast iron pipes, comprising the usual components for this type of use, as well as an adjuvant for improving the flowability characteristics of said product when it is being deposited and make them less dependent on its physical or physico-chemical characteristics. Said adjuvant can be in particular silicone oil, potassium siliconate or microsilica of density less than 0.1, as well as a mixture in any proportions of one or more of those.

Abstract: The invention concerns a silicon powder for making alkyl- or aryl-halogenosilanes, with particle-size distribution less than 350 ?m, and containing less than 3% and preferably less than 2% of particles having a size less than 5 ?m. Said powder enables to improve efficiency of synthesis reaction.

Abstract: The invention relates to an inoculant mixture for the treatment of molten cast iron, comprising 5 to 75% by weight of a ferro-silicon alloy of type A where Si/Fe>2, containing 0.005 to 3% by weight of rare earths, 0.005 to 3% bismuth, lead and/or antimony and less than 3% calcium, with a ratio (Bi+Pb+Sb)/TR of between 0.9 and 2.2 and 25 to 95% of at least one alloy of type B, based on silicon or ferro-silicon such that Si/Fe>2, containing calcium to a level such that the total amount of calcium in the mixture is from 0.3 to 3%. The above mixtures have a good granulometric stability over time and provide an efficient inoculation of cast pieces, in particular of thin pieces.

Abstract: Inoculation alloys for treating cast iron castings containing, by weight, 0.005% to 3% of an element selected from the group consisting of bismuth, lead and antimony, 0.3 to 10% of metals of the rare-earth group and optionally aluminum up to 5%, and calcium up to 1.5%, the remainder being ferro-silicon, lanthanum constituting more than 90% of the rare-earth metals contained in the composition. The inventive alloys enable efficient inoculation of cast iron and avoid occurrence of micro-shrinkage cracking in the cast parts. The alloys are conditioned in the form of slugs or powder.

Abstract: A method for preparing Al—Si alloys by introducing into the molten aluminum, at a temperature of between 700 and 850° C., metallurgical silicon particles having a granulometry of less than 10 mm. The silicon particles, upon reaching the temperature of the molten aluminum, have the property of fragmenting into smaller particles.

Abstract: A powder product for the protection of centrifugal casting molds for cast iron pipes includes an inoculating metal alloy and possibly mineral powders, and a strongly reducing metal that is volatile at the temperature of the liquid cast iron. The use of products according to the invention prevents accumulation of dirt on molds and improves the surface condition of the cast iron pipes.

Abstract: A method for preparing Al—Si alloys by introducing into the molten aluminum, at a temperature of between 700 and 850° C., metallurgical silicon particles having a granulometry of less than 10 mm. The silicon particles, upon reaching the temperature of the molten aluminum, have the property of fragmenting into smaller particles.

Abstract: A method for producing high-purity spheroidal graphite cast iron. The method comprises at least the steps of pretreating the melt in a closed converter and adding an inocculant when casting it into the mold. The solubility of the substances formed during the pretreatment and during the addition of the inocculant an be adjusted. The nucleation in the melt and the solidification in the mold can be brought into conformity by coordinating the pretreatment and the addition of inocculant.

Abstract: The invention concerns a silicon powder for making alkyl- or aryl-halogenosilanes, with particle-size distribution less than 350 &mgr;m, and containing less than 3% and preferably less than 2% of particles having a size less than 5 &mgr;m. Said powder enables to improve efficiency of synthesis reaction.

Abstract: A metallurgical-grade silicon for use in alkyl or aryl halosilane synthesis, and having a structure consisting of primary silicon crystals and intermetallic compounds, particularly of silicon, aluminum and calcium, wherein at least 90% of the primary silicon crystals have an aluminum content of 50-1000 ppm. This structure substantially enhances the reactivity of the silicon in the synthesis reaction.

Abstract: Powder product for the protection of molds for centrifugal casting of cast iron tubes, and a method for its production. The powder contains a mixture of a silicon-based inoculating agent and a mineral powder, the silicon-based inoculating product comprising waste masses from synthesis of alkyl- or aryl- halosilanes, from which tin and optionally copper has been removed. The mineral powder may contain at least one material selected from the group consisting of carbon and a fluoride.

Abstract: A process for the preparation of active silicon powder for use in the Rochow reaction consisting of grinding metallurgical silicon to a particle size less than 350 .mu.m in the presence of at least one catalyst and/or reaction promoter, in order to deposit this (these) element(s) on the grain surface, and an active silicon powder with a particle size of less than 350 .mu.m, with 0.01 to 0.1 g/m.sup.2 of copper, and/or 0.003 to 0.03 g/m.sup.2 of tin, and/or 0.003 to 0.03 g/m.sup.2 of phosphorus on the surface of the grains, for use in the Rochow reaction. The reactivity and selectivity of the powder are improved, and it has a shorter reaction incubation time.

Abstract: A metallurgical silicon or ferrosilicon in the form of granulates having an average size of less than 10 mm and in which the total oxygen concentration is less than 0.05% by weight, and a process for manufacture of this silicon or ferrosilicon consisting of a carbothermal reduction of silica in an electric oven, chlorine-based refining of the liquid metal, and granulation of the refined liquid metal in water under an inert atmosphere. The silicon may be used for silicone manufacture or as a constituent of an aluminum alloy, and the ferrosilicon, as a steel additive used to obtain magnetic sheet metals for electrical construction.