Abstract: A method for making a fiber-reinforced ceramic matrix composite article is disclosed wherein a ceramic matrix material in the form of a glass powder is combined with a fibrous reinforcing material such as a fiber tow, and the powder and tow are transported into a hot zone wherein they are consolidated together by winding under tension onto a collection mandrel at a temperature above the annealing temperature of the glass. High density composites are provided without the use of subsequent high pressure consolidation treatments.

Abstract: A method for forming barrier ribs for a gas discharge display panel which includes the steps of: covering a glass substrate with a conductive ITO film; covering the conductive film with photoresist; exposing the photoresist to radiation; developing the photoresist so as to selectively remove portions of photoresist thereby creating apertures in the photoresist; etching the panel conductive ITO film so as to remove the conductive film in the apertures; depositing barrier rib material including glass particles in the apertures formed in the photoresist until such time as the barrier rib material exceeds the thickness of the photoresist material; and, heating the foregoing combination to a temperature of approximately 580.degree. C. for about 10 minutes to burn off substantially all photoresist material and solidify the barrier material so as to form glass barrier ribs. The glass barrier ribs formed have a shape at least partially defined by the photoresist that was burned off.

Abstract: A heating furnace for heating a porous preform made of fine particles of quartz base glass for an optical fiber in an atmosphere comprising a fluorine-containing atmosphere to add fluorine to the preform and to vitrify the preform to produce a glass preform for an optical fiber, which comprises a heater and a muffle tube positioned inside the heater to separate a heating atmosphere from the heater, wherein at least the inner layer of the muffle tube consists of highly pure carbon.

Abstract: A flat-bottomed quartz glass crucible for the manufacture of monocrystalline silicon is made by disposing granular quartz particles on a flat base in a cylindrical mold. A vacuum is drawn on the particles through vacuum holes in the base to retain the particles on the base while the base and mold are rotated, and while the particles are heated to fuse them into a quartz glass crucible shape.

Abstract: A method for consolidating a green body is disclosed which involves: (1) drying and partially sintering the green body at a temperature above about 1000.degree. C. and in an atmosphere containing chlorine; (2) fully sintering the green body under vacuum at a temperature above about 1720.degree. C.; and (3) hot isostatic pressing ("hipping") the green body at a temperature above about 1150.degree. C. and at a pressure above about 100 psig. The process produces glass articles which have a low water content and are essentially bubble free.This is a continuation of co-pending application Ser. No. 07/271,709 filed Nov. 16, 1988, now abandoned which is a divisional application of application Ser. No. 07/052,619, filed May 20, 1987 now U.S. Pat. No. 4,789,389.

Abstract: Disclosed is the manufacture of a stress-free composite including reinforcing fibers embedded in and bonded to a matrix material such that differential contraction takes place in the matrix material relative to the fibers in response to temperature decrease. It involves embedding the fibers in the matrix material at an embedding temperature to obtain a composite precursor preparatory to subsequent consolidation thereof into the composite material at a consolidation temperature, and longitudinally stretching the fibers to such an extent that the longitudinal dimension of any portion of each fiber is substantially the same as that of the contiguous portion of the matrix material both at the consolidation temperature with the fiber stretched and at a predetermined operating temperature of the composite material in the absence of such stretching.

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: A method for fabricating a lens in which the lens composition is controlled by dynamic shaping and shadowing. A lens material is vaporized and directed to a substrate through an orifice which is rotating relative to the substrate about the lens axis and which has a non-uniform radial distribution. The lens material is condensed on the substrate to form a lens having a radially non-uniform but axially symmetrical distribution. Thereafter, the original orifice may be replaced by a complimentary orifice and another lens material vaporized and directed to the substrate through the replacement orifice which is also rotating relative to the substrate about the lens axis and which also has a non-uniform radial distribution. This second lens material condenses on the first condensed lens material to form a compound lens.

Abstract: A composite suitable for use as dental composite is provided by a glass material having a softening range of at least 10.degree. C. and having a particle size of less than 250 mesh to provide a precursor mix. The precursor mix is mixed with a fugitive pore forming material and a binder to form a pressable mix. The pressable mix is pressed at a pressure in excess of 5,000 pounds per square inch to form a sinterable mix. The sinterable mix is sintered for a period of time sufficient to remove said fugitive pore forming material and to form a sintered mass for crushing to form particles of less than 250 micrometers in size to be incorporated into a dental composite.

Abstract: This invention provides an optical medium which consists of a composite of a homogeneous inorganic oxide glass monolith with a microporous structure containing a liquid crystalline component.In one embodiment this invention provides a sol-gel process for producing a composite of a transparent homogeneous microporous inorganic oxide glass monolith and a liquid crystalline compound.

Abstract: The present invention relates to producing a polymeric alkali metal silicate glass powder by repeated steps of partial hydration and dehydration until the desired degree of polymerization has taken place. The polymeric alkali metal silicate glass may be utilized to produce aqueous polymeric alkali metal silicate glass solutions containing a suspension. This solution containing a suspension may be used as an adhesive, a binding agent, a laminating agent, coating agent and molding material.

Abstract: A method of producing a uniform silica glass block comprising using silica powder as a raw material, and treating it at high temperature and pressure by a hot press and/or a hot isostatic press in vacuum or in an inert gas atmosphere, preferably with a capsule of silica glass or a high-melting point metal. By conducting calcination in fluorine, chlorine or their compound gas and then in oxygen, the OH group content of the silica glass can be reduced dramatically.

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: Filter bodies are made by mixing borosilicate glass powder, potassium sulphate and 30% aqueous polyethylene glycol solution per kilogram of mixture. The mixture is filtered and dried and glass particles of a different size are mixed into the dried granulate. The resulting mixture is compressed at a pressure of 1000 bar to form blanks and sintered at about 860.degree. C. After cooling, the potassium sulphate is washed out of the blanks.

Abstract: A method of making a fiber reinforced glass matrix composite wherein a continuous length of fiber is impregnated with glass and at least partially consolidated to form a fiber-glass matrix system encompassing the continuous length of fibers, cutting the fiber-glass system into a plurality of short fiber reinforced composites, heating the short fiber reinforced composites to form a composite batch wherein the glass matrix is in a molten condition, and molding the composite batch to form a reinforced glass composite article with uniform random distribution of short fibers, is disclosed.

Abstract: Apparatus for pyrolytically forming a metal compound coating on an upper face of a hot glass substrate 1 comprises conveyor means 2 for conveying the substrate 1 in a downstream direction 3. A coating chamber 6 opening downwardly onto the path 1 and means 7 for spraying coating precursor downwardly towards the substrate.The spraying means 7 is located to spray the coating precursor solution from a height above the substrate path 1 of at least 75 cm. Heating means are provided for supplying heat to the spraying zone 9. Means such as aspirator boxes 39 is provided for generating aspirating forces on atmospheric material within the passageway 13 to encourage such material to flow along the substrate path to the downstream end (27) of the passageway and to enter exhaust ducting leading such material away from the substrate path.

Abstract: A telescope mirror blank having a supporting network core composed of sintered ceramic struts, and a method of forming such core from a thermally crystallizable, powdered glass and as a separate component from the faceplate, are disclosed. Optionally, the mirror faceplate may be formed in a similar manner.

Abstract: For the continuous casting of silicon, an electrically conductive bottomless crucible is circumferentially divided by axial slits and is positioned within an electrical induction coil. The slits form circumferential gaps of between 0.3 mm and 1.0 mm and the inner wall of the crucible is inclined by between 0.4.degree. and 2.0.degree., so that the crucible expands in the downstream direction of movement of the silicon. In order to reduce the temperature gradient of the solidified silicon to between 20.degree. C./cm and 100.degree. C./cm, an additional heating element is disposed downstream of the boundary surface between the molten and solidified silicon. The crucible may be cooled by forming the crucible as a double walled cylinder and flowing a coolant therethrough.

Abstract: An apparatus for granulating metallurgical melt, including a granulator (1) having a water supply (13), a trough (2) for supplying metallurgical melt thereto, and a rotary driven drum (3) having blades (6). A water tank (11) having an overflow device (12) is disposed under the drum (3). The granulator (1) and trough (2) are disposed in the interior of the drum (3), the lower part of the drum being disposed in the tank (11) below the overflow device (12), The apparatus is provided with a trough (22) for discharging granules from the drum (3).

Abstract: Alkali metal silicate glass is mixed with water to form an aqueous alkali metal silicate glass suspension, then dried to form a flexible solid alkali metal silicate glass product which may be heated to above the boiling temperature of water to produce a cellular product. The flexible solid product may be utilized as a flexible film, as an adhesive, a coating agent and a binding agent. The foamed product may be used for thermal and sound insulation.

Abstract: A heating oven is provided for processing glass materials, e.g., porous glass preforms, from which optical waveguide fibers are prepared. The oven includes a stationary elongated chamber, e.g., a silica muffle, for receiving the glass material which is to be processed. At least a portion of the chamber is surrounded by a stationary susceptor. The chamber is heated by moving an energized induction heating coil along a path parallel to the longitudinal axes of the susceptor and the chamber.

Abstract: A method for consolidating a porous glass preform is provided in which a preform is placed in a stationary elongated chamber and selected portions of the chamber, distributed along the chamber's length, are sequentially heated above the preform's sintering temperature. In certain preferred embodiments, the chamber is surrounded by an elongated susceptor and the heating is performed by moving an induction heating coil along a path parallel to the longitudinal axes of the susceptor and the chamber.

Abstract: A process for manufacturing open porous sintered bodies with large open pore volume and defined pore diameters and which at least predominantly consist of glass-ceramics. They are obtained by sintering a mixture of sinterable powder and an inorganic soluble salt with defined grade of grain, the melting point of which is above the densification temperature of the sinterable powder. For the formation of a molded body the mixture of sinterable powder and inorganic salt is submitted to a molding process. The molded body is sintered in a sintering process and the soluble salt being contained in the molded body is lixiviated. As a main constituent the sinterable powder contains a pulverized crystallizable glass powder.

Abstract: A multidirectionally fiber reinforced-glass matrix composite article is disclosed. The fiber reinforcement is precisely oriented in three or more directions to provide high strength and stiffness in each of the three or more directions. A method for making a multidimensionally fiber reinforced glass matrix composite article is also disclosed. The method includes impregnating a fiber preform with a colloidal suspension of inorganic material, cooling the impregnated fiber preform to precipitate the inorganic material, drying the preform, impregnating the preform with heated glass matrix material, and cooling the glass impregnated preform to form the multidirectionally fiber reinforced glass matrix composite article.

Abstract: This invention provides an optical medium which consists of a composite of a homogeneous inorganic oxide glass monolith with a microporous structure containing a liquid crystalline component. In one embodiment this invention provides a sol-gel process for producing a composite of a transparent homogeneous microporous inorganic oxide glass monolith and a liquid crystalline compound.

Abstract: This invention provides an optical medium which consists of an inorganic glass monolith with a microporous structure containing an organic component which exhibits nonlinear optical response.In one embodiment this invention provides a sol-gel process for producing a composite of a transparent homogeneous microporous inorganic oxide glass monolith and an organic compound which exhibits nonlinear optical response.

Abstract: A method of manufacturing a blank for a light-weight mirror. Graphite molding bodies are positioned at regular intervals on a base that functions as a mirror plate or backing plate. The base is surrounded up to the top of the molding bodies with a graphite wall. The interstices between the molding bodies and between the wall and the molding bodies are filled with granular quartz. The assembly is heated in an evacuated furnace to approximately 1730.degree. C. into a honeycomb-shaped supporting structure that is securely fastened to the base. The graphite molding bodies and wall are removed after cooling. Either a backing plate or a mirror plate in the form of another plate is applied to the resulting supporting structure.

Abstract: In a method of manufacturing glass bodies, in which a thixotropic suspension of SiO.sub.2 particles having a diameter in the range from 10 to 500 nm in a dispersing liquid is formed into a green body, after which the green body is purified and sintered, the suspension has a solid:dispersing liquid weight ratio of from 1:1 to 1:1.5, is passed through sieves having an aperture size in the range from 3 to 300 .mu.m under the action of sound or ultrasound, the sieved suspension is then concentrated by pumping off a part of the dispersing liquid under a vacuum and under the influence of sound or ultrasound, such that a solid:dispersing liquid weight ratio of about 1.3:1 is obtained, after which the concentrated suspension is introduced into a mould, heated to a temperature below the boiling point of the dispersing liquid to form a green body. The green body thus obtained is removed from the mould, cooled, and converted to a glass body.

Abstract: Method of and arrangement for manufacturing rotationally symmetrical porous solid bodies.A method of manufacturing rotationally symmetrical porous solid bodies, in which the starting material for the solid body in the form of a suspension consisting of the material for the solid body in solid form and a liquid dispersing agent, is introduced into a hollow mould whose geometry corresponds to that of the solid body to be formed, such that during the introduction of the suspension the hollow mould is rotated about its longitudinal axis, a certain quantity of solid of the suspension being deposited on the inner wall of the hollow mould, and excess residual suspension being removed, after which the green body thus formed is subjected to further process steps to manufacture the solid body, in which process suspension is introduced into the hollow mould in such doses that each time only thin solid layers having a thickness in the range from 10.sup.

Abstract: Gradient optical density transmissive light directing devices (24, 26, 28, 30) and fabrication thereof are disclosed herein. Examples of such devices include concentrators, lenses and compound lenses. The present invention teaches a process for the fabrication of glass light transmitting devices having a chosen gradient in index of refraction either bidirectionally (radially and longitudinally relative to an optical axis) or in three dimensions. The present invention further describes the design of several interesting optical devices by particular choices of the gradient in the index of refraction thereof. Such articles have numerous uses in the optics, optical fiber and solar technology industries for the purposes of designing compound lens systems using a single, integral lens, coupling light into fibers and for concentrating and directing light from a source having a significant angular variation to an energy collecting and/or conversion devices such as a photovoltaic cell, to name but a few applications.

Abstract: An improved sol-gel method is proposed for the preparation of a transparent silica gel block, in which a deposit of fine silica particles having a controlled particle diameter as prepared by hydrolyzing an alkoxy silane in the presence of ammonia is dispersed in a silica sol solution prepared in an acidic condition and settled therein to form a structure of closest-packing prior to gelation, drying, sintering and vitrification so that silica glass blocks can be obtained with low volume shrinkage from the wet gel in an improved yield without cracks, bubbles and haziness. The improvement can be further enhanced when two separately prepared deposits of silica particles having larger and smaller particle diameters are dispersed as combined in the silica sol solution, especially, when the particle diameter in one deposit is not exceeding 22.5% of that in the other deposit.

Abstract: Apparatus for use in pyrolytically forming a metal oxide coating on an upper face of a hot glass substrate 1 in sheet or ribbon form comprises conveyor means 2 for conveying the substrate 1 in a downstream direction 3 along a path also indicated at 1 and a roof structure 5 defining a coating chamber 6 opening downwardly onto the path and comprising a passageway 11 along which coating precursor vapor and oxidizing gas can be conducted downstream in contact with the upper substrate face during the conveyance of the substrate. The roof structure 5 defines, in or adjacent the upstream end of the passageway 11, a mixing zone 7 which opens downwardly onto the substrate path 1. Means such as spray nozzle 35 is provided for injecting coating precursor material into the mixing zone 7 from a height of at least 50 cm above the level of the substate path 1.

Abstract: A method for forming articles which include silica-containing glass bodies, as well as the resulting articles, are disclosed. In accordance with the method, silica-containing gel particles are fused to form a glass body. In contrast to previous such methods, these particles are formed by mechanically, substantially uniformly subdividing either a substantially cohesive gel body, or an ungelled or partially gelled sol capable of yielding a substantially cohesive gel body, to form substantially uniformly sized, wet gel particles. Significantly, only substantially cohesive gel bodies which are also substantially elastic are useful in the invention, i.e., mechanical subdivision of non-elastic gel bodies results in these bodies undergoing plastic flow to yield non-particulate, pasty masses.

Abstract: A process for the production of a glass by the vacuum melting method using silica as a raw material is disclosed, comprising filing a silica fine powder in a suitable vessel, heating it in the presence of an accelerator for phase conversion to obtain a porous formed body consisting of a cristobalite phase, and then heating and melting the formed body in vacuo. According to the present invention, a transparent and active glass having a high quality can be produced at an inexpensive cost.

Abstract: A method is described of producing an elongated glass body, particularly a preform for SiO.sub.2 -base optical waveguides, in which starting glass powder material is shaped to a porous body and the latter is sintered to form a glass body. In order to obtain uniform density throughout the porous body, the starting glass powder material is filled into and simultaneously compacted in a mold. Subsequently, the powder material compacted during the filling is consolidated by a heat treatment to result in the porous body. Molds of different design for the production of tubular or rod-shaped porous bodies are described.

Abstract: Porous bodies of a material comprising SiO.sub.2 as the main constituent are heated by passing a zone of high temperature through the body. This high temperature zone is obtained by irradiation with light of a wavelength which is obsorbed by the porous part of the body, but which is not absorbed by the densified part of the body. The device preferaby comprises a rotatable radiation source surrounding the body to be densified.

Abstract: In a device for producing mold glass bodies, a molding cavity is defined by two mold halves and by two mouth ring halves. One single nozzle head is used for spraying a lubricant on both the inner faces of the mold halves and the connection faces of the mouth ring halves which are to contact the mold halves.

Abstract: Silicon monoxide grains finer than 10 mesh are vacuum hot pressed to form a glass billet which can than be used to provide silicon monoxide of a size and/or shape suitable for vapor deposition purposes.

Abstract: Aluminosilicate optical glass without boron oxide, comprising 60-95 mols % silica and at least 2 mols alumina, the remainder being made up of at least one oxide of a metal selected from silver and thallium. The glass may also contain caesium. Optical waveguide preforms and methods of making the same are also disclosed.

Abstract: The present invention is directed to the preparation of hybrid composite bodies composed of an essentially alkali-free, alkaline earth aluminosilicate glass matrix reinforced with SiC whiskers and continuous ceramic fibers.

Abstract: The process of constructing a multi-layer glass-ceramic circuit is disclosed. One or more glass-ceramic substrates is formed from a slurry or molten glass particles and ceramic which was formed at a temperature wherein the glass particles are molten and the ceramic particles are solid. After an electrical conductor pattern is applied on at least a surface of one of the glass-ceramic structures, at least two glass-ceramic structures are stacked on one another with the electrical conductor pattern therebetween and heated until the glass of each glass-ceramic structure bonds with adjacent glass so as to form the multi-layer structure.

Abstract: The potential for fused cast ceramic refractories to release stones into molten material with which it is in contact is reduced by subjecting the refractory to a vacuum pretreatment to remove gases from the glassy phase of the refractory. Preferably the treatment is carried out when the refractory is in a molten state.

Abstract: In the production of an article of extremely pure synthetic silicon dioxide, wherein silicon tetrachloride is mixed with water to effect hydrolysis, the resulting hydrolysis product is dried, and the resulting dried particulate product is further processed into the desired article, the improvement which comprises employing a ratio of silicon tetrachloride to water so that the hydrolysis product is in the form of a gel, distilling by-product hydrochloric acid out of the gel, preliminarily drying the gel at 100.degree. to 1000.degree. C. to produce an initial product, milling the initial product into a fine granulate at room temperature, separating from the milled granulate a fraction with a particle size of about 40 to 1000 .mu.m, and drying the screened-out granulate fraction while slowly heating to no more than 1400.degree. C. to form the resulting dried particulate product that is further processed into the desired article. As a result, high quality bubble free articles are produced.

Abstract: Alkali metal silicate glass is mixed with water to form an aqueous alkali metal silicate glass suspension, then dried to form a flexible solid alkali metal silicate glass product which may be heated to above the boiling temperature of water to produce a cellular product. The flexible solid product may be utilized as a flexible film, as an adhesive, a coating agent and a binding agent. The foamed product may be used for thermal and sound insulation.

Abstract: A process for preparing a cartridge for disposal of a radioactive waste liquid, which comprises filling glass fibers in a mold, heat-treating the fibers for partial fusion and molding them into a molded product of a predetermined shape, wherein at least one member selected from the group consisting of boric acid, silicic acid, lithium borate, lithium silicate, zinc borate, zinc silicate, an organic silane, a silica sol, an oil emulsion, and an alumina sol, is applied to the glass fibers or to the molded product.

Abstract: Compositions for encapsulating electronic components are provided which comprise a blend of a curable resin and an ultra-pure silica filler. The filler is composed of fused silica granules which are prepared from a gel of a silicon-containing organic compound, such as TEOS, and which have a uranium content of less than about 0.1 parts per billion and a thorium content of less than about 0.5 parts per billion. The compositions can be readily manufactured in commercial quantities at reasonable costs and are particular well-suite for encapsulating components, such as, high density RAMs, which are sensitive to alpha particles.

Abstract: A method of manufacturing glass bodies, in which the starting material for the glass body, being an extrusion mass consisting of microdispersed SiO.sub.2 particles, a binder and a dispersing liquid, is used to form a porous green body by extrusion, which is subsequently dried, purified and sintered, the extrusion mass, which is shaped by the nozzle of an extruder, being extruded into a transfer vessel in which the extruded body is tempered towards the gelification point of the binder present in the extrusion mass, a liquid being contained in the transfer vessel, which cannot or substantially not be mixed with the dispersing liquid present in the extrusion mass, and which cannot be mixed with the binder present in the extrusion mass; and an arrangement for carrying out this method.

Abstract: This invention provides an optical medium which consists of a composite of homogeneous inorganic oxide glass monolith with a microporous structure containing a liquid crystalline component.In one embodiment this invention provides a sol-gel process for producing a composite of a transparent homogeneous microporous inorganic oxide glass monolith and a liquid crystalline compound.

Abstract: A method of making optical waveguides is disclosed in which, to fabricate a preform, glass forming pulverulent material is filled into a mold by means of one or more screw conveyors. The quantity of glass forming pulverulent material filled into the mold per unit of time is increased by passing a suitable gas through the apparatus. Thus, the quantity conveyed per unit of time can also be controlled by adjusting the gas pressure. By using a dry gas, the moisture content of the powder can be reduced.

Abstract: In one embodiment this invention provides novel microporous inorganic oxide glass monolith structures, which have improved mechanical strength and optical transparency. An invention glass monolith is produced by a novel sol-gel process, which utilizes trioxane as an essential additive during the gellation phase, to provide a glass monolith with micropores having uniformity of size and shape.