Abstract: The present invention relates to glass compositions suitable for cathode ray tube faceplates which are essentially free from readily reducible metal oxides, MgO, and fluorine, and which consist essentially, in weight percent on the oxide basis, of:______________________________________ SiO.sub.2 60-63 BaO 5.5-8.5 ZrO.sub.2 + Al.sub.2 O.sub.3 >4-6.25 Li.sub.2 O 0.25-0.8 CaO 1.5-4.0 Sb.sub.2 O.sub.3 0.25-0.55 Na.sub.2 O 7.25-9.25 TiO.sub.2 0.25-0.75 As.sub.2 O.sub.3 0-0.25 K.sub.2 O 6-8.25 ZrO.sub.2 4-6.25 Sb.sub.2 O.sub.3 + As.sub.2 O.sub.3 0.35-0.75 SrO 5.5-8.5 Al.sub.2 O.sub.3 0-<2 CeO.sub.2 0.15-0.5.

Abstract: The present invention is directed to a four-step process for molding glass articles of high precision and excellent surface figure. A glass preform having an overall geometry closely approximating that of the desired final product is placed into a mold, the mold and preform are brought to a temperature at which the glass exhibits a viscosity between 10.sup.8 -10.sup.12 poises, a load is applied to shape the glass into conformity with the mold, and thereafter the glass shape is removed from the mold at a temperature above the transformation range of the glass and annealed.

Abstract: An extrusion die for extruding a honeycombshaped structure having rectangular channels. The die is formed of a hard, rigid material, preferably metal, and includes a body plate and an abutting face plate. The outlet face of the body plate is brazed to the inlet face of the face plate. The body plate has a plurality of slightly staggered primary feed holes, the outlet ends of each communicating with an associated feed reservoir, the latter each defined by a recess or depression in the inlet surface of the face plate. Each feed reservoir communicates with the inlet ends of three associated secondary feed holes. The outlet surface of the face plate integrally carries a plurality of intersecting slot segments defining rectangular pins. The outlet end of each secondary feed hole communicates with and feeds an associated intersection of groove segments.

Abstract: This invention is directed to the production of unitary, transparent glass articles demonstrating exceptionally high flexural and impact strengths composed of an interior portion and an integral surface compression layer. The articles are prepared by contacting glass bodies consisting essentially, in mole percent, of 14-24% R.sub.2 O, wherein R.sub.2 O consists of 0-5% Li.sub.2 O, 0-5% K.sub.2 O, and the remainder Na.sub.2 O, 17-21% Al.sub.2 o.sub.3, 45-60% SiO.sub.2, 3-6% TiO.sub.2 and/or ZrO.sub.2, and 0-2% P.sub.2 O.sub.5, the sum of those components constituting at least 85% of the total composition, at a temperature above the annealing point of the glass with a source of Li.sup.+ ions to replace at least part of the Na.sup.+ ions and, if present, K.sup.+ ions in a surface layer with a corresponding amount of Li.sup.+ ions and to react the Li.sup.+ ions with Al.sub.2 O.sub.3 and SiO.sub.2 in the surface layer to form crystallites of beta-quartz solid solution nucleated by the TiO.sub.2 and/or ZrO.sub.2.

Abstract: A glass delivery system is disclosed which includes a molybdenum delivery pipe surrounded by molten glass and inductively heated by a water cooled induction heating coil surrounding the molybdenum pipe and spaced apart therefrom by means of refractory material.

Abstract: A porous glass optical waveguide preform is formed by depositing a coating of glass particulate material on the lateral surface of a core which may be a porous glass body continuously produced by the axial deposition of glass particles. The core rotates and moves longitudinally in one direction with respect to two flame hydrolysis burners which emit streams of glass particles having different compositions. In addition, the two burners reciprocatingly move with respect to a portion of the length of the core. The speed of each burner varies as it traverses along its path of reciprocating motion. The thickness of the layer produced by a burner at a given point is inversely related to the speed of the burner as it passes that point. The layers formed by the completion of a single traverse by both burners combine to form a conically-shaped layer, the composition of which varies from the base toward the apex thereof.

Abstract: A method is disclosed for extruding thin-walled ceramic bodies. The method involves mixing into a homogenized batch a granular ceramic, a binder, a soluble oxidizing agent and a matrix precursor in amounts sufficient to provide a substantially water-free extrudable mixture. The batch is extruded into an atmosphere containing SO.sub.2 which permeates the extrudate and reacts with the oxidizing agent to form SO.sub.3 in situ. The SO.sub.3 catalyzes polymerization of the furfuryl alcohol to a rigid solid which prevents deformation of the extrudate.

Abstract: A method is set forth for controlling the height of batch material on the surface of a molten bath in a cold-crown or vertical melting furnace by measuring the level of the upper surface of the batch material, the level of the fusion line between the batch and bath, and the effective hydrostatic head of the molten glass and batch material thereon over a predetermined height at such known fusion line level. The thickness of the batch blanket is then determined from the level of the fusion line and the measured level of the top of the batch blanket, and power input and rate of batch distribution are controlled to maintain such desired levels and accordingly a predetermined batch thickness, by continuously monitoring the level of the batch material and the effective hydrostatic head.

Abstract: This invention is directed to the production of nitride-based ceramic bodies selected from the group of AlN and Si.sub.3 N.sub.4 which can be sintered to near theoretical densities at temperatures at least 200.degree. C. lower than those required for the pure materials. Such bodies are densified through the addition of a metal fluoride selected from the group of aluminum, barium, calcium, srtrontium, yttrium, the lanthanide rare earth metals, and mixtures thereof. Up to 80% by weight of said metal fluoride may be included but, generally, such additions will be held between 5-30% by weight. AlN bodies exhibiting very high thermal conductivity can be prepared by sintering with a metal fluoride selected from the group of barium, calcium, strontium, yttrium, the lanthanide rare earth metals, and mixtures thereof.

Abstract: There is disclosed a laminated ceramic structure including a facing member and a backing member, the two members being bonded together either directly or through an intermediate layer, the facing member being formed from a very hard ceramic such as a carbide having a KHN.sub.100 value in excess of 1000 kg/mm.sup.2, the backing member being a glass or glass-ceramic matrix having an enhanced capability or absorbing impact energy, preferably being fiber reinforced and having an energy absorbing capacity in excess of 10 KJ/m.sup.2.

Abstract: A vapor phase method for making a metal halide material useful for the manufacture of an infrared transmitting optical waveguide fiber or other optical device, and the use of the method for making such a device, wherein a halogenated beta-diketonate of a metal to be incorporated in the device is converted to the corresponding metal halide by controlled decomposition of the halogenated diketonate, are described.

Abstract: Substantially spherical mono-sized particles of zirconia can be prepared by the forced hydrolysis of an aqueous solution of zirconyl chloride. A zirconyl chloride solution having a molarity up to about 0.4 is heated for at least 72 hours at a temperature of at least 95.degree. C. to generate suspended particles of hydrated zirconium oxide, which are recovered and calcined to provide the mono-sized zirconia powders. In preferred embodiments, mono-sized powders of a mixture of zirconia with one or more of its stabilizing metal oxides is prepared by precipitating the metal in the form of its hydroxide onto pre-formed zirconium-containing particles.

Abstract: The invention is a flexible mask for use in charging a flowable material into selected cells of a honeycomb structure and is of particular utility in charging a sealing material into the ends of selected cells of such a structure during fabrication of solid particulate fitler bodies and other selectively plugged honeycomb structures. The mask has a central body with a set of openings extending therethrough which allow passage of the flowable material through to the selected cells and a second set of protrusions extending from one of the surfaces of the mask which are used to align the mask to the end face of the structure and which extend into and sealably cover the cells which are not to receive the flowable material. The mask may be formed from a polymer, preferably an elastomer, using any of three disclosed die apparatuses.

Abstract: The invention is a flexible mask for use in charging a flowable material into selected cells of a honeycomb structure and is of particular utility in charging a sealing material into the ends of selected cells of such a structure during fabrication of solid particulate filter bodies and other selectively plugged honeycomb structures. The mask has a central body with a set of openings extending therethrough which allow passage of the flowable material through to the selected cells and a second set of protrusions extending from one of the surfaces of the mask which are used to align the mask to the end face of the structure and which extend into and sealably cover the cells which are not to receive the flowable material. The mask may be formed from a polymer, preferably an elastomer, using any of three disclosed die apparatuses.

Abstract: This invention relates to a method for forming a product from a naturally occurring phyllosilicate, the method comprising the steps of:(a) exposing the phyllosilicate to a source of exchangeable cations to effect a change in the chemical makeup of the phyllosilicate interlayer by ion transfer;(b) exposing the ion-exchanged phyllosilicate to an expanding agent selected from the group consisting of a primary aminocarboxy acid, lysine orotate, and glycylglycine to expand the cell spacing and cause gel formation;(c) flocculating the gel;(d) forming a gel-floc interface; and(e) withdrawing the flocculated gel from that interface.

Abstract: Disclosed is an optical waveguide fiber having a core surrounded by a layer of cladding material. The core is characterized in that it includes a region of depressed refractive index. The inner radius a.sub.i of this region is greater than zero, and the outer radius a.sub.o thereof is less than the core radius. By appropriately selecting the core index depression characteristics such as radial location, width, depth and shape, a fiber having the desired waveguide dispersion characteristics can be designed. Dispersion minimization over a wide wavelength range can be achieved, without adverse effect on system loss.

Abstract: A porous glass optical waveguide preform is formed by depositing a coating of glass particulate material on the lateral surface of a core which may be a porous glass body continuously produced by the axial deposition of glass particles. The core rotates and moves longitudinally in one direction with respect to two flame hydrolysis burners which emit streams of glass particles having different compositions. In addition, the two burners reciprocatingly move with respect to a portion of the length of the core. The speed of each burner varies as it traverses along its path of reciprocating motion. The thickness of the layer produced by a burner at a given point is inversely related to the speed of the burner as it passes that point. The layers formed by the completion of a single traverse by both burners combine to form a conically-shaped layer, the composition of which varies from the base toward the apex thereof.

Abstract: This invention is directed to the production of glass-ceramic materials especially designed for substrates in integrated circuit packaging. The glass-ceramics can be prepared from thermally crystallizable glasses that can be sintered into an integral glass-ceramic having a dielectric constant less than 6 and containing willemite as the predominant crystal phase. The overall composition of the glass-ceramic consists essentially, in weight percent of 15-45% ZnO, 10-30% Al.sub.2 O.sub.3, and 30-55% SiO.sub.2. Where desired, a nucleating agent selected from the group consisting of 8-12% ZrO.sub.2 and 0.001-0.05% of a noble metal selected from the group consisting of Au, Pd, and Pt may be included.

Abstract: A machine for grinding the cavity in a mold for optical lenses has a spherical grinding tool which is precisely positioned with respect to the center line of a rotary table upon which it is mounted by air slides, which air slides move the tool in orthogonal directions. The carriages of the air slides move relative to center rails. A film of air between the top plate of each air slide and the center rail is supplied at a pressure which supports the weight on the carriage. When precise alignment between the grinding tool and the center line is obtained, a first air supply is cut off and a second air supply is maintained to lock the air slides in the position of alignment.

Abstract: A composite glass ceramic material which comprises silicon nitride (Si.sub.3 N.sub.4) whiskers in a glass ceramic material comprising nitrogen doped cordierite, which composite material has greatly increased strength at elevated temperatures, good microwave transparency, and good thermal shock resistance.The invention further comprises a method for manufacturing the composite material by blending ground nitrogen doped cordierite glass with between about 5 and about 50 percent Si.sub.3 N.sub.4 whiskers by weight of glass. The blend is then formed into a desired shape and is sintered at an elevated temperature of from about 1000.degree. to 1400.degree. C.The invention also includes the novel nitrogen doped cordierite glass and glass ceramic made therefrom.