Abstract: In a known composite material with a fused silica matrix there are regions of silicon-containing phase embedded. In order to provide a composite material which is suitable for producing components for use in high-temperature processes for heat treatment even when exacting requirements are imposed on impermeability to gas and on purity, it is proposed in accordance with the invention that the composite material be impervious to gas, have a closed porosity of less than 0.5% and a specific density of at least 2.19 g/cm3, and at a temperature of 1000° C. have a spectral emissivity of at least 0.7 for wavelengths between 2 and 8 ?m.

Abstract: Crucible compositions and methods of using the crucible compositions to melt titanium and titanium alloys. More specifically, crucible compositions having extrinsic facecoats comprising a rare earth oxide that are effective for melting titanium and titanium alloys for use in casting titanium-containing articles. Further embodiments are titanium-containing articles made from the titanium and titanium alloys melted in the crucible compositions. Another embodiment is a crucible curing device and methods of use thereof.

Abstract: The present invention provides a heat conduction device included crucible, which includes: a crucible body and a heat conduction device arranged in the crucible body. The heat conduction device has a tree-like configuration, which includes a heat-dissipative trunk and multiple levels of heat dissipative branches mounted to the heat-dissipative trunk. Each level of the heat dissipative branches includes a plurality of branch units and the branch units are arranged to project out from an outer surface of the heat-dissipative trunk.

Abstract: Crucible compositions and methods of using the crucible compositions to melt titanium and titanium alloys. More specifically, crucible compositions having intrinsic facecoats that are effective for melting titanium and titanium alloys for use in casting titanium-containing articles. Further embodiments are titanium-containing articles made from the titanium and titanium alloys melted in the crucible compositions. Another embodiment is a crucible curing device and methods of use thereof.

Abstract: The invention relates to a shaped body comprising a substrate with a firmly adhering separating layer, wherein the separating layer comprises 92-98 wt. % silicon nitride (Si3N4) and 2-8 wt. % silicon dioxide (SiO2) and wherein the separating layer has a total oxygen content of ?8 wt. % and a hardness of at least 10 HB 2.5/3 according to DIN EN ISO 6506-1. The invention further relates to a process for producing such a shaped body, a coating suspension for use in such a process and the use of a shaped body according to the invention in the field of corrosive nonferrous metal melts.

Abstract: A method of fabricating a reaction container according to the disclosure comprises putting graphite power in a molded member; and pressing the molded member, wherein the graphite powder comprises first graphite powder and second graphite powder having different particle sizes. A vacuum heat treatment apparatus comprises a chamber, a reaction container in the chamber, and a heat member heating the reaction container in the chamber, in which the reaction container comprises graphite, and the reaction container has a concentration in the range of 1.8 to 2.0.

Abstract: PVD and HPHT methods and apparatus for producing materials, for example nitrides, are disclosed.

Abstract: There is provided a graphite crucible including a bottom part, a body part, a treatment part including an input port, and a gas discharge part that is closed at a lower end side and is opened at an upper end side of the body part. Since graphite is porous, at the time when graphite is eluted into an object to be treated or is consumed, a gas in the pores of a graphite crucible is released as air bubbles continuously into the molten object to be treated. Therefore, gasification of a gas dissolved inside the object to be treated can be enhanced, and bumping of the object to be treated can be prevented.

Abstract: A reinforced refractory container having a cast refractory container which includes a sidewall defining an interior volume, the sidewall having inner and outer surfaces, the container cast from a castable refractory composition, and a wound, continuous fiber tensile reinforcement structure integrated with the container sidewall. A method of fabricating the reinforced refractory container is also provided.

Abstract: A graphite crucible has a cylindrical body with an upper opening for receiving a sample for analysis and a disk-shaped pedestal base. The pedestal base includes a bottom surface with a centrally formed circular indentation. An inwardly projecting concave arcuate annular indentation extends between the body and pedestal base with a smoothly curved radius of curvature. The upper and lower walls of the arcuate indentation diverge outwardly at an angle of from about 56 to about 60°. The pedestal base includes a bottom surface with a centrally formed circular indentation.

Abstract: The present invention provides a non-monolithic crucible for sapphire production and methods of making and using the same.

Abstract: A silica crucible and a fabricating method thereof are provided. The silica crucible includes a vitreous silica body having an inner surface and an outer surface, the inner surface of the vitreous silica body defining a cavity adapted for containing a molten material or a powder material; and a first coating layer formed on the inner surface of the vitreous silica body. The first coating layer is formed by pyrolysing a composite of aluminum, magnesium, calcium, titanium, zirconium, radium, chromium, selenium, barium, yttrium, cerium, hafnium, tantalum, tin or silicon under a predetermined temperature. The first coating layer substantially includes of a nonhomogeneous material, and an interface is defined by the homogeneous material and the nonhomogeneous material between the vitreous silica body and the coating layer. The first coating layer has strong adhesion capability and guarantees the coating layer will not be easily peeled off or removed.

Abstract: A combined graphite tube is combined by stacking a plurality of graphite short-tubes together, where each graphite short-tube includes a upper coupling portion and a lower coupling portion, the upper coupling portion is positioned on a top face of a upper side of the graphite short-tube; and the lower coupling portion is positioned on a bottom face of a lower side of the graphite short-tube, and corresponds to the upper coupling portion, allowing the upper coupling portion of each graphite short-tube to be propped against the lower coupling portion of another graphite short-tube; the graphite short-tubes are fused and coupled together by means of a sintering treatment after the graphite short-tubes are stacked together. Whereby, the combined graphite tube of the present invention may be utilized in silicon smelting, and may be coupled to an enough length of graphite tube depending on requirements or derive a graphite crucible, capable of improving silicon smelting efficiency.

Abstract: The present disclosure relates to a silica-based crucible material that includes, before sintering or firing, selected amounts of a thermal expansion stabilizer component (B2O3 and Ca2SiO4) which impart improved thermal shock resistance and enhanced ability to withstand repeated thermal cycling, to a sintered or fired crucible made of the material. An illustrative embodiment of the invention provides a crucible material whose chemical composition comprises, in weight %, about 91% to about 98% SiO2, about 1% to about 8% thermal stabilizer component, and up to about 1.0% of additional oxides including MgO, Al2O3 Fe2O3, CaO and ZrO2.

Abstract: Articles for use with highly reactive alloys that include a graphite crucible having an interior, and at least a first protective layer applied to the interior of the graphite crucible in which the graphite crucible having the first protective layer is used for melting highly reactive alloys.

Abstract: Methods for making refractory crucibles capable of managing thermal stresses and suitable for melting highly reactive alloys, the method involving providing a crucible having at least a facecoat and a backing, heating at least one retaining ring, applying the at least one retaining ring about at least a portion of the backing of the crucible; and allowing the at least one retaining ring to cool and shrink-fit about the crucible.

Abstract: An object of the invention is to provide a quartz glass crucible reduced in the generation of vibration occurring on the surface of a silicon melt and free from the generation of rough surface and cristobalite spots, yet capable of pulling up single crystal silicon stably and at high yield even in long-term operations; it is also an object to provide a method for producing the same. In a quartz glass crucible for pulling up single crystal silicon comprising a crucible base body having a bottom part and a straight shell part with an inner layer provided to the inner surface thereof, the quartz glass crucible is characterized by that said inner layer comprises a synthetic quartz glass layer from the lowest end to at least a height of 0.25 H; a naturally occurring quartz glass layer or a mixed layer of naturally occurring quartz glass and synthetic quartz glass extended in a range of from at least 0.5 H to 0.

Abstract: Methods for reducing carbon contamination when melting highly reactive alloys involving providing a graphite crucible having an interior, applying at least a first protective layer to the interior of the graphite crucible, placing a highly reactive alloy into the crucible having the first protective layer, and melting the highly reactive alloy to obtain a melted alloy having reduced carbon contamination.

Abstract: Disclosed is a multilayer structured quartz glass crucible, for pulling up silicon single crystal, whose structure has at least three layers comprising: a translucent outer layer made of naturally occurring quartz glass and having a large number of pores, a translucent intermediate layer, made of synthetic quartz glass and having a large number of pores, and a transparent inner layer substantially free from pores and made of a synthetic quartz glass. Thermal convection within the silicon melt is suppressed by use of the quartz glass crucible, thereby preventing oscillation on the surface of the silicon melt. A method for producing the quartz glas crucible is also disclosed.

Abstract: Refractory ceramics and composite materials consisting of nitrides, mixed nitrides and oxides, and oxynitrides of Group IV metals Hf, Zr, Ti, and Group III metals Sc, Y, and lanthanides La through Lu, are used to form refractory articles, or as coatings for refractory articles. These materials and articles have high resistance to molten metals, molten salts, erosion, and high temperature corrosive environments, and can be engineered to have desirable thermal and electrical properties. In particular the articles are crucibles, molds, containment vessels, and spray nozzles, and most particularly these articles are made of or coated with the Hf compounds.

Abstract: An article of relatively pure silica, and a furnace and method of producing the article. The article is produced by collecting molten silica particles in a refractory furnace in which at least a portion of the refractory has been exposed to a halogen-containing gas to react with contaminating metal ions in the refractory.

Abstract: The present is invention is concerned with a heat deformable crucible used for the preparation of glass-ceramic materials and the resulting dental restorations. The crucible has a base and a side portion and is formed from the sintering of silica with a particulate mixture of borosilicate glass having a composition in weight percent of 78% SiO2, 15% B2O3, 2.5% Al2O3 and 4.5% Na2O3.

Abstract: A crucible 40 having an inner surface 42 not wetted by a melt which shrinks when it solidifies is provided with indentations 41 in the walls of the crucible to support an ingot grown in it. Supporting the crystal provides a gap between the bottom of the ingot 44 and the inner surface of the bottom of the crucible. The gap allows more uniform heat transfer from the bottom of the crucible than is provided when there is no gap; the gap provides a controllable temperature gradient between the interior and exterior of the crucible. To direct propagation of the growth of a macrocrystal, the bottom of the crucible is provided with at least one set of multiple grooves in parallel relationship with each other. Preferably a second set of multiple grooves in parallel relationship with each other intersect the grooves of the first set at an angle chosen depending upon the lattice structure of the macrocrystal to be grown. A macrocrystal grown in a crucible with twin sets of angulated grooves produces single crystals.

Abstract: This invention relates to a corrosion-resistant member having a resistance to plasma of a halogen based corrosive gas, which comprises a main body and a corrosion-resistant layer formed on a surface of the main body and containing a fluoride of at least one element selected from the group consisting of rare earth elements and alkaline earth elements.

Abstract: A large diameter quartz crucible with an inner diameter of 22 inches or more comprises an opaque silica glass outer layer having bubbles of 10 .mu.m to 250 .mu.m in diameter and 5 mm to 20 mm in thickness and a transparent silica glass inner layer having 0.5% or less in a bubble content and 0.3 mm or more in thickness which is molten and integrated with an inner surface of the outer layer. The outer layer has an OH group concentration of 80 ppm or less and the gas pressure in a bubble in the outer layer is lower than atmospheric pressure so that a volume expansion ratio of the bubble is minimized when being heated in condition of pulling a single crystal.

Abstract: A unibody, monolithic, one-piece negative draft crucible for a MBE effusion cell. The crucible maximizes capacity, uniformity and long term flux stability, and minimizes oval defects, depletion effects, and short term shutter-related flux transients. The invention also provides a method and mandrel apparatus for making a unibody containment structure, such as a crucible formed of PBN, having a negative draft, via chemical vapor deposition.

Abstract: A jig used for heat treatment made from an SiC-coated silicon carbide material, wherein the SiC film is coated by the CVD method on a silicon carbide matrix in which silicon has been impregnated and wherein there are no pores with a diameter of 2 .mu.m or larger in the outer layer of the matrix within 200 .mu.m from the interface of the SiC film and the silicon carbide matrix when observed by a scanning electron microscope at a magnification of 400 times. The jig is manufactured by producing an SiC film on the surface of a silicon carbide matrix in which silicon has been impregnated by introducing a raw material compound for producing the SiC film and forming the SiC film at a temperature from 1000.degree. C. to 1290.degree. C. under a pressure from 500 to 760 Torr in a non-oxidative atmosphere. The jig exhibits superior resistance to high temperature heating cycles and excellent high thermal shock resistance required for heat treatment in semiconductor manufacturing.

Abstract: A unibody, monolithic, one-piece negative draft crucible for an MBE effusion source. The crucible maximizes capacity, uniformity and long term flux stability, and minimizes oval defects, depletion effects, and short term shutter-related flux transients. The invention also includes an effusion source employing such a crucible, as well as a method and mandrel apparatus for making a unibody containment structure, such as a crucible formed of PBN, having a negative draft, via chemical vapor deposition.

Abstract: A unibody, monolithic, one-piece negative draft crucible for a MBE effusion cell. The crucible maximizes capacity, uniformity and long term flux stability, and minimizes oval defects, depletion effects, and short term shutter-related flux transients. The invention also provides a method and mandrel apparatus for making a unibody containment structure, such as a crucible formed of PBN, having a negative draft, via chemical vapor deposition.

Abstract: An apparatus for manufacturing a phosphor for use in an electroluminescent panel includes a storage body that is permeable to a fluid, and an open boat for containing a phosphor material. The open boat is stored in, and has a shape corresponding to, the storage body. The open boat and the storage body are housed in a reactor. A gas supply section introduces a nitrogen gas and a halogen gas into the reactor, and a heating device heats the reactor. A pressure control device selectively evacuates the reactor and introduces a gas pressure into the reactor to control the pressure in the reactor to be in a range from 10.sup.-3 to 1140 Torr.

Abstract: Graphite substrate holders for employment in apparatus for chemical vapor deposition of diamond decrease the tendency of the formed diamond sheets to crack or shatter upon separation from the substrates. Said holders and the substrates therein preferably have rounded edges, to suppress crack formation at sharp corners. The holders are preferably coated, at least in part, with a tie-layer and a hydride-forming metal such as niobium. Also, certain maximum distances between the edges of the holder and substrates are preferably maintained in order to prevent contact of diamond with a heated filament employed for thermal activation.

Abstract: A multi-piece crucible for high temperature applications comprises a tubular side wall member having a lip on the inside surface and a bottom member or members forming a container for containing a melt of a material during a high temperature melt-casting operations. The multi-piece design prevents cracking of the crucible or leakage of the melt from the crucible during the melt-casting operation. The lip of the tubular member supports the bottom member. The contacting surfaces where the lip of the tubular side wall member contacts the bottom member of the multi-piece crucible contains a ceramic sealing material. The ceramic sealing material forms a seal sufficient to prevent the melt of the material from leaking out of the multi-piece crucible during the melt-casting process. The multi-piece crucible is made of a material which is chemically inert to the melt and has structural integrity at the melting point temperature of the melt, or of a material coated with such a material.

Abstract: The invention concerns a composite material for a receptacle for transferring molten metal.It is comprised of a refractory material and a frame chosen in the group comprised of mineral refractory wires and metallic wires.Application to the foundry industry.

Abstract: A pyrolytic boron nitride boat having a cavity suitable for use in growing and doping semi-conductor crystals such as gallium arsenide and said cavity having a roughened surface formed of substantially uniform projected no nodules, disturbances, or ridges.

Abstract: A boron nitride crucible having a closed end, an open end, an internal surface and an external surface, and wherein at least a portion of the external surface, preferably proximate the open end of the crucible, has a duplex coating comprising an undercoat of pyrolytic graphite and a top coat of pyrolytic boron nitride. A process for making the boron nitride crucible is also disclosed.

Abstract: An enclosable vessel for containing a silicon nitride article during sintering in a furnace to protect the silicon nitride article from thermal decomposition and contamination reactions with furnace materials comprises a closeable walled container formed of a reaction bonded silicon nitride material having an opening to allow interior placement of the silicon nitride article within the walled container. This box is used to replace silicon nitride powder which has heretofore been used to cover silicon nitride articles during sintering.

Abstract: An improved molten metal containment vessel is disclosed in which wetting of the vessel's inner wall surfaces by molten metal is inhibited by coating at least the inner surfaces of the containment vessel with one or more rare earth oxysulfide or rare earth sulfide compounds to inhibit wetting and or adherence by the molten metal to the surfaces of the containment vessel.

Abstract: Smelting crucible of mineral materials for melting down materials by electrical heating. In the base (2) of the crucible, there is a tapping opening (3) and, in the region of the upper edge of the crucible, there is a flange (4) for mounting the crucible in a holding device. To accomplish the objective of making the crucible suitable for use with larger charge weights, the crucible is surrounded inventively by a reinforcing device (10, 11), which can be stressed in tension and which connects the flange (4) with the base (2) of the crucible.

Abstract: An inside lining for the reaction chamber of an electric low shaft furnace, particularly for producing high-purity silicon from silicon oxide by carbothermic reduction, is provided which has a melting crucible of dense graphite and a thermal insulation, whereby at least the floor of the reaction chamber has an inside lining of high-purity carbon. The inside lining is constructed from graphite, graphite grits or lampblack. The inside lining provides good thermal insulation and does not further contaminate the molten metal due to furnace materials. The inside lining prevents a loss of material in that seepage of molten metal into the insulation is prevented by a rapid dropoff of the temperature in the insulation below the melting point of the metal.

Abstract: A quartz glass crucible adapted for use in a process for pulling a single crystal semiconductor material having an opaque outer substrate of a quartz glass with a relatively high bubble content and an inner transparent glass layer which is substantially free from bubbles. The crucible is produced while the substrate is supported by a rotating mould by forming an atmosphere of high temperature gas and supplying a metered quantity of powders of quartz to the high temperature gas atmosphere to have the quartz powders molten at least partly and directed toward an inner surface of the substrate to be adhered thereon.

Abstract: In the boat growth method of the IIIb-Vb group compound, the quartz boat is tridymitized on at least the surface thereof so as to prevent wetting of the boat due to the melt of the compound and hence to enhance the yield of a single crystal.

Abstract: A refractory product is shown in the form of a dense sintered alumina-chromia, zirconia-alumina-silica, zirconia-alumina body, or zirconia-chromia-alumina having less than about 8% of homogeneously distributed closed porosity formed by sintering an intimate interdispersion of fine particles of alumina-chromia, zirconia-alumina-silica, zirconia-alumina, or zirconia-chromia-alumina.

Abstract: The inventive vessel, e.g. crucible, made of a refractory inorganic material such as boron nitride has a multi-layered wall structure which is an integral alternate lamination of layers of higher density and layers of lower density. Such a multi-layered structure can be formed by the procedure of pyrolytic chemical vapor deposition in the course of which the concentration of the gaseous reactants, e.g. boron trichloride and ammonia, in the atmosphere is changed, i.e. increased or decreased, under control so that the resultant deposited boron nitride layer has different densities in the portions deposited before and after the concentration change. By virtue of the multi-layered wall structure, the vessel has outstandingly improved resistance against thermal shock and can withstand prolonged use or many times of repeated use at high temperatures without breaking or crack formation.

Abstract: A pyrolytic boron nitride crucible is provided. The crucible contains at least five wall layers consisting of first and second wall layers. The thickness of each of the first wall layers is 5 to 100 microns and the thickness of each of the second wall layers is 1/50 to 1/1 of that of the first wall layer. The total thickness of the entire wall layers is 0.5 to 3 mm. The first wall layer is bonded to and laminated alternately with the second wall layer.

Abstract: A crucible/susceptor system is described in which the walls of the crucible and the susceptor cavity are sloped outward in an angle sufficient for the force of gravity to exceed the inward pulling forces created by the high surface tension of molten silicon allowing the softened quartz crucible walls to settle into and form to the sloped walls of the susceptor thereby improving heat transfer from the susceptor to the molten silicon and improving the reproducibility of the system.

Abstract: A pyrolytic boron nitride article has a uniform structure 0.5 or less nodules/cm.sup.2 in average all through the overall surface of the article and 2 or less nodules in any portion of a unit square centimeter on the surface of the article. The pyrolytic boron nitride article is produced by depositing boron nitride through a vapor phase, using a boron halide gas and an ammonia gas as the starting materials. In production, the ammonia gas or a gas mixture containing the ammonia gas is not contacted directly with graphite at 300.degree. to 1850.degree. C.

Abstract: A compound-semiconductor single-crystal-manufacturing apparatus comprises a crucible for holding a molten raw material of GaAs and a liquid capsule element of B.sub.2 O.sub.3, a crucible holder, a heat element concentrically surrounding the crucible, and a heat-shielding unit surrounding the heat element, for use in manufacturing a GaAs single crystal by progressively pulling it up from the raw molten material held in the crucible by the liquid encapsulated Czochralski (LEC) process. The heat-shielding unit and crucible holder are formed by molding a sintered aluminum nitride (AlN) element.

Abstract: Evaporator crucible for vacuum depositing systems, having a crucible bottom with at least one bottom opening for the introduction of material in rod form for evaporation. At a distance from the bottom opening there is provided at least one metal crucible rim which preferably is provided with a coolant passage. To solve the problem of reducing the heat losses, the crucible rim is provided internally on at least a part of its depth with a lagging comprising ceramic material. This lagging preferably comprises individual ceramic building blocks which are preferably compressed from magnesium oxide.

Abstract: There is provided a crucible for containing salt baths for the boriding of steels which has a high service life made of a steel which consists of (or consists essentially of) 0.05-0.8% carbon, 0.8-2.5% silicon, 0.1-2.0% manganese, 0-1.5% aluminum, 6-30% chromium, 4-39% nickel and the balance iron.

Abstract: An apparatus for producing a single crystal according to the CZ method, which comprisesa closed container consisting of upper and lower halves and having a shaft for pulling up the single crystal, at least a part of which contacting with said vapor of the elements is made of a material containing an element of the same group of the periodic table as that of component elements of the single crystal, a gap between said shaft and the container and an opening between said upper and lower halves of the container being sealed with a sealing material,at least one reservoir positioned in the container for supplying vapor of a volatile component element of the single crystal, anda heating means provided around the container; wherein a hot zone of the apparatus including the container is made of a material which has an X-ray absorption coefficient not larger than 5 cm.sup.2 /g, and said material of the hot zone has such thickness that X-ray transmittance through the whole hot zone is 10.sup.