Abstract: A protective and abradable coating composition is suitable for application on rolls and more particularly for application on conveyor rolls. The abradable coating is suitable for use in high temperature applications. Rolls incorporating the coating may be produced and used according to disclosed processes and procedures. Application of the composition to rolls reduces corrosion by aluminium melt, and enables the removal of built-up substances by friction. The life time of the roll is thereby increased.

Abstract: A refractory article used at high temperature contains a silica, calcium silicate or mullite matrix with at least a surface having an open porosity filled at least partially with a sulfate, phosphate, or carbonate salt or a mixture of sulfate, phosphate or carbonate salts. The refractory article is resistant to the corrosion and build-up of non-ferrous metals and their alloys.

Abstract: A protective and abradable coating composition is suitable for application on rolls and more particularly for application on conveyor rolls. The abradable coating is suitable for use in high temperature applications. Rolls incorporating the coating may be produced and used according to disclosed processes and procedures. Application of the composition to rolls reduces corrosion by aluminium melt, and enables the removal of built-up substances by friction. The life time of the roll is thereby increased.

Abstract: The present invention relates to refractory articles in general having improved surface properties. The objective of the invention is to propose an improvement of the refractory articles comprised of a fused silica matrix which will overcome the some of the defects while keeping the excellent known properties of the fused silica matrix. This objective is reached when a sintered ceramic phase is present in the porosity of at least a portion of at least a surface of the matrix. The present invention also relates to a process for producing such an article.

Abstract: A protective coating is prepared for, and applied to, crucibles used in the handling of molten materials that are solidified in the crucible and then removed as ingots. Crucibles containing this protective coating may be used for the solidification of silicon. The coating has a specified oxygen content and contains a mineral binder and silicon nitride or silicon oxynitride.

Abstract: A crucible and method for the crystallization of silicon utilize release coatings. The crucible is used in the handling of molten materials that are solidified in the crucible and then removed as ingots. The crucible does not require the preparation of a very thick coating at the end user facilities, is faster and cheaper to produce, presents an improved release effect and allows the production of silicon ingot without cracks. The crucible includes a base body, a substrate layer containing silicon nitride, an intermediate layer containing silica, and a surface layer containing silicon nitride, silicon dioxide and silicon.

Abstract: A crucible for the treatment of molten silicon includes a basic body with a bottom surface and lateral walls defining an inner volume. The basic body comprises at least 65% by weight of silicon carbide, and from 12 to 30% by weight of a constituent selected from silicon oxide or nitride. Moreover, the basic body comprises at least one silicon oxide and/or nitride coating, at least on the surfaces defining the inner volume of the crucible.

Abstract: The present invention relates to refractory articles in general having improved surface properties. The objective of the invention is to propose an improvement of the refractory articles comprised of a fused silica matrix which will overcome the some of the defects while keeping the excellent known properties of the fused silica matrix. This objective is reached when a sintered ceramic phase is present in the porosity of at least a portion of at least a surface of the matrix. The present invention also relates to a process for producing such an article.

Abstract: A crucible for the treatment of molten silicon includes a basic body with a bottom surface and lateral walls defining an inner volume. The basic body comprises at least 65% by weight of silicon carbide, and from 12 to 30% by weight of a constituent selected from silicon oxide or nitride. Moreover, the basic body comprises at least one silicon oxide and/or nitride coating, at least on the surfaces defining the inner volume of the crucible.

Abstract: A protective coating is prepared for, and applied to, crucibles used in the handling of molten materials that are solidified in the crucible and then removed as ingots. Crucibles containing this protective coating may be used for the solidification of silicon. The coating has a specified oxygen content and contains a mineral binder and silicon nitride or silicon oxynitride.

Abstract: A crucible and method for the crystallization of silicon utilize release coatings. The crucible is used in the handling of molten materials that are solidified in the crucible and then removed as ingots. The crucible does not require the preparation of a very thick coating at the end user facilities, is faster and cheaper to produce, presents an improved release effect and allows the production of silicon ingot without cracks. The crucible includes a base body, a substrate layer containing silicon nitride, an intermediate layer containing silica, and a surface layer containing silicon nitride, silicon dioxide and silicon.

Abstract: The invention relates to a crucible for the crystallization of silicon and to the preparation and application of release coatings for crucibles used in the handling of molten materials that are solidified in the crucible and then removed as ingots, and more particularly to release coatings for crucibles used in the solidification of polycrystalline silicon. The objective of the inventor was to provide a crucible which does not require the preparation of a very thick coating at the end user facilities, which is faster and cheaper to produce and which presents a stronger coating with an improved adherence to the walls. It has now been found that these problems can be solved with a crucible for the crystallization of silicon comprising a) a base body comprising a bottom surface and side walls defining an inner volume; b) an intermediate layer comprising 50 to 100 wt. % of silica at the surface of the side walls facing the inner volume; and c) a surface layer comprising 50 to 100 wt.

Abstract: The invention relates to a crucible for the crystallization of silicon and to the preparation and application of release coatings for crucibles used in the handling of molten materials that are solidified in the crucible and then removed as ingots, and more particularly to release coatings for crucibles used in the solidification of polycrystalline silicon. The objective of the inventor was to provide a crucible which does not require the preparation of a very thick coating at the end user facilities, which is faster and cheaper to produce and which presents a stronger coating with an improved adherence to the walls. It has now been found that these problems can be solved with a crucible for the crystallization of silicon comprising a) a base body comprising a bottom surface and side walls defining an inner volume; b) an intermediate layer comprising 50 to 100 wt. % of silica at the surface of the side walls facing the inner volume; and c) a surface layer comprising 50 to 100 wt.

Abstract: The present invention relates to refractory articles for guiding or conveying a solidified material comprising a vitreous silica basis, in particular rollers or guiding elements and to a process for the manufacture of said articles which do not show the pickup problems normally observed with the articles of the art. The refractory articles of the invention comprise a vitreous basis and, homogeneously distributed therein, a carbonaceous material.

Abstract: The invention relates to a roller (21) from a refractory material, for example in vitreous silica, for transporting a flat article provided at its end with a new arrangement for rotationally driving it as well as to an assembly of such a roller and its driving device. This roller (21) comprises an external surface (2), an inner surface (5) and two side surfaces (12), at least one side surface having indentations (22) parallel to the roller axis (3) and spaced apart from the external (2) and inner surface (5) for receiving rotationally driving pins (8), it is characterized in that at least one of the indentations (22) of the roller is provided with a metal jacket (24). The invention permits to avoid the breakage of the roller around the driving indentations.

Abstract: The invention concerns a crack-free insulating refractory material made from a composition comprising 20-80% by weight of a ceramic matrix, 5-40% by weight of insulating microspheres, 0.5-15% by weight of one more binders, 5-20% by weight of a metal or a metal alloy able to melt during the preheating or the first minute of use and 0-25% by weight of water. The ceramic matrix is preferably comprised of vitreous and non-vitreous grains.

Abstract: The invention encompasses a method for manufacturing a high density indium oxide/tin oxide (ITO) sintered body, as well as the ITO sintered body itself. The method produces an ITO sintered body of high homogeneity for use as a sputtering target in manufacturing processes where thin, transparent and electrically conductive ITO layers are deposited over transparent substrates. The method comprises the steps of preparing a slurry whose solid constituents consist of a finely divided mixture of between 99 and 50 weight percent of In.sub.2 O.sub.3 and 1 to 50 weight percent of SnO.sub.2, and between about 0.05 through 0.25 percent of a sintering agent formed from an oxide of, only one of the group consisting of aluminum, magnesium, yttrium, and silicon; forming the resulting slurry into a green body having a density of between about 4.0 and 4.8 gm/c.sup.3 and heating the green body to a sintering temperature of between about 1500 and 1600 C.

Abstract: The invention concerns a fired magnesia-carbon shape having a combination of properties making it especially suitable for slide gate plates, inserts for such plates and for pouring nozzles useful in casting aggressive steels. The fired refractory shape is formed from a batch consisting essentially of, by weight percent,2 to 8 finely divided graphite (natural or synthetic);3 to 8 aluminum metal powder;1 to 5 of finely divided silica and/or a silicon yielding powder;an effective amount of carbon bond forming resins;and the balance coarse and fine magnesia grains.The magnesia grains should contain less than about 0.02 weight percent boron oxide. After firing, the shape is characterized by a carbon bonding system including a spinel (magnesia-alumina) phase plus aluminum carbide bonding the magnesia-carbon matrix. The refractory shape is preferably carbon impregnated after firing to further enhance its properties.

Abstract: The invention concerns a material for covering the metal contacting surfaces of casting elements such as slide gate valves and casting nozzles and shrouds to resist steel erosion and alumina deposition during the continuous casting of aluminum killed steel.It is comprised of a fused mixture of calcium oxide and zirconia, with a calcium oxide content of between about 20% and about 60% by weight and preferably between about 20% and about 50% by weight, the composition may include a binder producing carbon/carbon bonds by sintering. The material may also include a ceramic bond or may be applied as a fused layer by plasma spraying.

Abstract: The invention concerns a material for the covering of casting shrouds.It is comprised of a calcareous composition capable of liberating calcium oxide at a temperature at least equal to 1400.degree. C., its calcium content, expressed in calcium oxide, is between ca. 10% and ca. 60% and preferably between ca. 20% and ca. 50%, the said calcareous composition is bound by a binder chosen in the group comprised of those utilizing carbon/carbon bonds by sintering.Application to the metallurgy of ferro-alloys.