Abstract: Bonded ceramic matrix composite structures such as ceramic panels or beams, and a method for making them, are described, the structures comprising ceramic facing sheets to which are bonded one or an array of relatively thin-walled, hollow, high-stiffness channeled ceramic support elements, the support elements being of modular design with each support being formed by a continuous composite ceramic wall incorporating multidirectional fiber reinforcement and defining a central channel extending, in the bonded structure, in a direction generally parallel with the ceramic facing sheets.

Abstract: This invention is related to glasses particularly useful in the fabrication of multifocal lenses for ophthalmic applications. The inventive glasses exhibit a refractive index between 1.599-1.602, an Abbe number between 40.5-41.5, a density between 2.64-2.66 g/cm.sup.3, a transmission of visible radiation at 400 nm through a thickness of 10 mm greater than 83%, a softening point between 670.degree.-680.degree. C., a birefringence upon sealing, measured as described, between -150 and +150 nm/cm, and consist essentially, expressed in terms of weight percent on the oxide basis, of:______________________________________ SiO.sub.2 52-57 K.sub.2 O 11.0-16.0 B.sub.2 O.sub.3 2.5-7.0 CaO 2-3.5 Al.sub.2 O.sub.3 0-1 ZrO.sub.2 1-1.5 Li.sub.2 O 0.3-0.8 TiO.sub.2 15.0-16.2 Na.sub.2 O 5.4-8.2 As.sub.2 O.sub.3 0.1-0.

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: This invention is directed to lead-free and, where desired, cadmium-free frits for glazes and enamels, said frits consisting essentially, in mole percent on the oxide basis, of______________________________________ SiO.sub.2 55-75 Na.sub.2 O 3-9 B.sub.2 O.sub.3 8-13 ZrO.sub.2 2-5 Al.sub.2 O.sub.3 0.5-3 BaO 0.5-16 ______________________________________Various inert refractory materials may be included as fillers.

Abstract: There is disclosed a lithium aluminosilicate glass body encased within, and integral with, a thin, compressive, semicrystalline layer containing beta-eucryptite and/or beta-quartz solid solution crystals, and a method of producing such body. The layer has a substantially lower thermal coefficient of expansion than the glass, but has the same chemical composition as the glass. That composition, in percent by weight on a calculated oxide basis is 55-67% SiO.sub.2, 5.0-7.5% Li.sub.2 O, 22-28% Al.sub.2 O.sub.3, 0-2% Na.sub.2 O and 0-10% ZnO, the molar ratio of R.sub.2 O+RO to Al.sub.2 O.sub.3 being greater than one. Controlled crystallization procedure is described whereby the crystallized layer can be produced in a relatively short time.

Abstract: A method is disclosed for making a step-index optical fiber having a steep refractive index gradient between core and cladding. Core glass particles comprising a base glass and a refractive index-increasing dopant are deposited on a mandrel. The mandrel is removed and the resultant soot preform is consolidated to form a core preform having a dopant-poor surface region. The core glass preform is stretched and the hole therein is closed to form a core bait rod. Cladding glass soot is deposited on the core bait rod at a density which is at least 0.5 g/cc. This is accomplished by directing the flame from an auxiliary burner onto the core bait rod immediately prior to the deposition of cladding soot thereon. The resultant preform is consolidated and drawn into an optical fiber. In another embodiment, the etched core preform is overclad with a layer of cladding glass, and the composite preform is stretched prior to applying a second overclad layer.

Abstract: A method is provided of preparing high-purity mixtures of zirconia and another metal oxide substantially free of sodium oxide impurity. Trioxydizirconium ion and a salt of another metal in an aqueous solution are added to a highly basic solution, resulting in the homogeneous precipitation of the combined hydroxides or hydrous oxides. The precipitate is recovered, washed with the water and then with an organic solvent, and then dried, most preferably employing an azeotropic distillation procedure. The resulting material is then calcined to provide a mixture of zirconia with the other metal oxide. In a preferred embodiment, the zirconia mixtures are in the form of fine powders which can be sintered to form a product having greater than 99% of its theoretical density.

Abstract: This invention relates to the production of laminated structures consisting essentially of a light weight interior member prepared from a glass, glass-ceramic, or ceramic, an exterior member prepared from a glass, glass-ceramic, or ceramic, and a bonding member prepared from a glass, glass-ceramic, or ceramic. The light weight interior member may be composed of a porous body, a corrugated body, or a honeycomb body. In a preferred embodiment, at least one of said members is reinforced through the entrainment of ceramic fibers and/ or whiskers. In the most preferred embodiment, each exterior and interior member is reinforced through the entrainment of ceramic fibers and/or whiskers and the bonding member is reinforced through the entrainment of ceramic whiskers.

Abstract: The method of forming an optical fiber splice is described wherein a hollow cylindrical glass member is provided, the member having a bore along the longitudinal axis thereof. The member is formed with tapered, funnel-like apertures at each end thereof for improved insertion of optical fibers. Optical fibers are inserted into the ends of the splicing member and cemented in place.

Abstract: Oxide-coated whiskers suitable for consolidation into or incorporation within a whisker-reinforced composite ceramic article are provided by dispersing inorganic whiskers in a colloidal oxide sol, separating the dispersion into fine droplets, and drying the droplets to provide a solid particulate product comprising the coated whiskers. The continuous oxide coating on the whiskers provides protection and aids in composite consolidation.

Abstract: A single-mode transmission optical fiber may have a bandwidth much greater than that necessary to transmit a desired predetermined maximum data rate. The single-mode fiber is connected to a bandwidth limiting device comprising the serial combination of an input optical fiber, a mode converter and multimode fiber. If the multimode fiber is capable of propagating two modes, for example, the mode converter converts the LP01 signal from the transmission fiber to the LP01 and LP11 modes. These two modes propagate at different speeds through the multimode fiber. Means connected to the output end of the multimode fiber detects the two modes. If the time delay difference .DELTA.t between the two modes is small with respect to the width of a pulse in the transmitted pulse train, the pulse train will be detected without distortion. Transmission at a higher data rate causes .DELTA.t to be large with respect to pulse width.

Abstract: Whisker-toughened ZrO.sub.2 products containing 5-20 volume percent SiC whiskers of relatively low aspect ratio (<20) in a stabilized polycrystalline ZrO.sub.2 matrix are provided, exhibiting a room temperature fracture toughness (K.sub.IC) at least 1.25 times that of the ZrO.sub.2 matrix, with relatively low porosity and good strength.

Abstract: A method is provided of crystallizing strong-bound zeolites on the surfaces of a monolithic ceramic substrate by hydrothermally treating the substrate, in the presence of active silica, with a caustic bath to zeolitize the silica. According to various embodiments of the invention, the active silica can be present as a component of the caustic bath, in the form of a dried coating pre-deposited on the substrate, or as a separate phase of the monolithic substrate, homogeneous dispersed within the ceramic material.

Abstract: A low loss fiber optic coupler is fabricated by forming a coupler preform having a plurality of spaced glass cores extending longitudinally through a matrix of glass having a refractive index lower than that of the cores. The preform is heated and stretched to form a glass rod which is then severed into a plurality of units. Heat is applied to the central region of each unit while the ends of the unit are pulled apart to elongate and taper inwardly the heated central region, whereby the cores of the unit are more closely spaced and are of smaller diameter at the central region than they are at the ends of the unit. The unit is then provided with a plurality of optical fibers, one of which extends from each of the cores at the endfaces of the unit. A preferred method of providing the optical fibers involves forming the coupler preform of a matrix glass that is easily dissolved in a solvent.

Abstract: A method and apparatus for molding precision optical quality glass elements having complex and concave surfaces requires the apportionment of relative movement between two opposing mold surfaces. First and second molds are contained within a floating alignment sleeve, thereby defining a mold cavity within which an essentially arbitrarily-shaped glass preform is placed. The first mold is moved in the alignment sleeve until stopped by a calibrated standoff. Thereafter, pressing is continued with the second mold moving in the alignment sleeve until opposing surfaces are completely formed at substantially the same time.

Abstract: This invention relates to the fabrication of three-layer composite lenses especially suited for ophthalmic applications. The lenses comprise a thin layer of an inorganic glass, desirably photochromic glass, an organic plastic, and an organic adhesive exhibiting flexibility and can be cured at temperatures in the vicinity of room temperature. In general, the linear coefficient of expansion of the glass ranges between about 60-120.times.10.sup.-7 /.degree.C. and that of the plastic between about 200-700.times.10.sup.-7 /.degree.C.

Abstract: A grinding wheel coolant distributor system is set forth utilizing a frusto-conical receptacle attached to a grinding wheel body which receives coolant from a fixed single point inlet and delivers the coolant along radially-outwardly and diverging inner sidewalls to a plurality of passages extending through the grinding wheel body to a distributor plate, which in turn, through centrifugal force distributes the coolant in a uniform thin film flow to the active abrasive face of the grinding wheel.

Abstract: In the process for applying a protective plastic coating to a glass optical waveguide fiber by the application of a curable liquid coating material thereto and the subsequent curing of the liquid coating to a protective plastic layer, the surface of the glass optical fiber is conditioned prior to the application of the liquid coating material thereto by replacing air adjacent the fiber surface with a selected gas preferably exhibiting high solubility in the liquid coating composition and resisting bubble formation in the liquid coating layer as it is formed.

Abstract: Alkali boroaluminosilicate glasses exhibiting moderately high thermal expansion coefficients, good melting characteristics, and a UV transmittance of at least 80% in 1 mm thickness at a wavelength of 254 nm are described, such glasses consisting essentially of about 58-62%, SiO.sub.2, 15-18% B.sub.2 O.sub.3, 11.5-14.5% Al.sub.2 O.sub.3, 1-2.5% Li.sub.2 O, 5.5-6.5% Na.sub.2 O, 0-2% K.sub.2 O, and 0-0.6% Cl.