Abstract: A polished glass disk medium substrate suitable for use as a substrate for a hard disk, a hard disk containing the substrate and methods for making the substrate. The substrate containing glass forming raw materials may be formed so as to have a Young's modulus of 110 or higher.

Abstract: A polished glass disk medium substrate suitable for use as a substrate for a hard disk, a hard disk containing the substrate and methods for making the substrate. The substrate containing glass forming raw materials may be formed so as to have a Young's modulus of 110 or higher.

Abstract: A polished glass disk medium substrate suitable for use as a substrate for a hard disk, a hard disk containing the substrate and methods for making the substrate. The substrate containing glass forming raw materials may be formed so as to have a Young's modulus of 110 or higher.

Abstract: A polished glass disk medium substrate suitable for use as a substrate for a hard disk, a hard disk containing the substrate and methods for making the substrate. The substrate containing glass forming raw materials may be formed so as to have a Young's modulus of 110 or higher.

Abstract: A crystalline glass-ceramic article composed of a cordierite phase of cordierite crystals or aggregates of near-parallel crystallites, having a formula of either Mg2Al4Si5O18 or AxByMg2Al4+x+2ySi5−x−2yO18. With the first formula, the average size of the cordierite crystals or aggregates is less than 70 micrometers, and the mean coefficient of thermal expansion from 22° C. to 800° C. (CTE) is less than 9×10−7/° C. With the second formula, A is either sodium or potassium, B is either strontium or barium, the sum of x and y is not less than 0.01, and when either x or y equal zero, the CTE is not more than 14×10−7/° C. The article is especially suitable as a filter or catalyst substrate.

Abstract: Enclosed are crystallized glasses suitable for a substrate for an information recording medium such as a magnetic disc, optical disc, or optomagnetic disc, a substrate for information recording medium using such a crystallized glass substrate, and an information recording medium using such a substrate for information recording medium. The crystallized glasses are capable of providing a glass substrate having a high Young's modulus, as well as excellent mechanical strength, surface flatness, and heat resistance and having an excellent surface smoothness upon polishing. Glass substrate having an excellent surface smoothness using such a crystallized glass are also disclosed.

Abstract: Low thermal expansion ceramics contains a cordierite crystal phase, wherein a phase of a crystalline compound containing at least one element selected from the group consisting of an alkaline earth element other than Mg, a rare earth element, Ga and In, is precipitated in the grain boundaries of said crystal phase, said ceramics has a relative density of not smaller than 95%, a coefficient of thermal expansion of not larger than 1×10−6/° C. at 10 to 40° C., and a Young's modulus of not smaller than 130 GPa. That is, the ceramics has a small coefficient of thermal expansion, is deformed very little depending upon a change in the temperature, has a very high Young's modulus and is highly rigid and is resistance against external force such as vibration. Accordingly, the ceramics is very useful as a member for supporting a wafer or an optical system is a lithography apparatus that forms high resolution circuit patterns on a silicon wafer.

Abstract: A ceramic filter comprising at least 50 mass % of a cordierite aggregate having a particle size of at least 74 &mgr;m and a binder, wherein said binder comprises at least 10 mass % of a fine powder of cordierite having a particle size of less than 74 &mgr;m and &bgr;-spodumene, and the mass ratio of said &bgr;-spodumene to said fine powder of cordierite is from 0.6 to 2.5, and wherein said ceramic filter has a pressure loss coefficient m′ of at least 30×10−8 cm2 as represented by the following formula and as calculated with respect to pores having diameters corresponding to at least {fraction (1/10)} of the volume-based median pore diameter: m′=(Vp/Sp)2×(&rgr;) wherein Vp (cm3/g) is a cumulative pore specific volume, Sp (cm2/g) is a cumulative pore specific surface area, and &rgr; is a cumulative porosity.

Abstract: The present invention provides a honeycomb structure that is able to suppress separation of a loaded catalyst layer much better than the prior art, and its production process. This honeycomb structure is made in the form of honeycombs partitions having for their main component cordierite having a chemical composition of 45-55 wt % SiO2, 33-42 wt % Al2O3 and 12-18 wt % MgO, and fifty or more pores (number/1.65 mm2) having a mean diameter of 1-20 &mgr;m are provided in the surfaces of the partitions.

Abstract: A high rigidity glass-ceramic substrate for a magnetic information storage medium has a ratio of Young's modulus to specific gravity within a range from 37 to 63 and comprises Al2O3 within a range from 10% to less than 20%. Predominant crystal phases of the glass-ceramic substrate consist of (1) cordierite or cordierite solid solution and (2) one or more crystals selected from the group consisting of Spinel crystal, Spinel crystal solid solution, enstatite, enstatite solid solution, &bgr;-quartz and &bgr;-quartz solid solution.

Abstract: An improved porous ceramic article and a method for forming such porous ceramic article. A mixture of ceramic particles and pliable organic hollow spheres is prepared in a liquid, typically as a suspension. The article is formed by pressing, slip casting, extruding or injection molding the mixture. The article is dried to remove the liquid, and then is fired so that the ceramic particles are bonded such as by sintering, and the organic spheres are burned off, resulting in a strong porous ceramic article having uniformly spaced interconnected voids.

Abstract: Multiphase ceramic materials for use in multilayered device fabrication may be fabricated by providing novel glassy precursor materials of a preferred composition, with operable amounts of a non-glassy filler materials. The combined materials are fired at appropriate temperatures, so that a non-glassy anorthite type phase is formed. Material so fabricated is formed in a self-limiting process, in that reaction between the glassy precursor material and the non-glass filler material is terminated when one constituent of the glassy precursor material is fully consumed. The materials of the instant invention, fabricated according to the method disclosed herein, demonstrate excellent dielectric constant, and electrical loss characteristics.

Abstract: An electrochemical device for separating oxygen from an oxygen-containing gas comprises a plurality of planar ion-conductive solid electrolyte plates and electrically-conductive gas-impermeable interconnects assembled in a multi-cell stack. Electrically-conductive anode and cathode material is applied to opposite sides of each electrolyte plate. A gas-tight anode seal is bonded between the anode side of each electrolyte plate and the anode side of the adjacent interconnect. A biasing electrode, applied to the anode side of each electrolyte plate between the anode seal and the edge of the anode, eliminates anode seal failure by minimizing the electrical potential across the seal. The seal potential is maintained below about 40 mV and preferably below about 25 mV. A gas-tight seal is applied between the cathode sides of each electrolyte plate and the adjacent interconnect such that the anode and cathode seals are radially offset on opposite sides of the plate.

Abstract: Cordierite body of CTE at 25-800.degree. C. of .ltoreq.4.times.10.sup.-7 C, at least 85% of porosity having pore diameter of 0.5-5.0.mu.; or >4-6.times.10.sup.-7 C.sup.-1, porosity at least 30 vol %, at least 85% of porosity has pore diameter 0.5-5.0.mu.. Raw materials talc, Al.sub.2 O.sub.3 source, and kaolin, calcined kaolin, and/or silica, and optionally spinel, particle diameter of talc .ltoreq.3.0.mu., of Al.sub.2 O.sub.3 source <2.0.mu., kaolin is <35 wt % of raw materials when particle diameter is <2.0.mu., are blended with vehicle and aids into plastic mixture. Green body is formed, dried, fired at 1370.degree. C.-1435.degree. C. When particle diameter of talc is <2.0.mu., and Al.sub.2 O.sub.3 source is <20 wt % of raw materials, and dispersible high surface area Al.sub.2 O.sub.3 source having particle diameter of <0.3.mu., is <5.0 wt % of raw materials, and particle diameter of kaolin is <2.0.mu., heating rate from 1150.degree. C.-1275.degree. C. is >200.degree. C./hr.

Abstract: The invention relates to a glass ceramic in which mica and ZrO.sub.2 are present in crystallized form, containing:K.sub.2 O: 0-9% by weightNa.sub.2 O: 0-9% by weight with the condition that Na.sub.2 O and K.sub.2 O together make up at least about 4% by weight,SiO.sub.2 : 35-60% by weightMgO: 10-25% by weightAl.sub.2 O.sub.3 : 7-30% by weightZrO2: 4-12% by weightF.sup.- : 2-10% by weight which is essentially free of lithium, calcium, strontium and barium, to a process for its production and to its use as a tooth replacement.

Abstract: Low expansion, low porosity cordierite bodies having a CTE at 25-800.degree. C. of <4.times.10-7C-1 and total porosity of <20%, or CTE of >4.times.10-7C-1 but <9.times.10-7C-1 and total porosity of <12%, or a CTE of >9.times.10-7C-1 but <15.times.10-7C-1 and total porosity of <10%. They are produced by selecting cordierite-forming raw materials in specific combinations of talc, spinel, kaolin, calcined kaolin, Al203-forming material, MgO-forming materials, and silica, in various particle size combinations. The raw materials are intimately blended with an effective amount of vehicle and forming aids and plastically shaped into a green body that is dried and fired at a temperature of about 1370.degree. C. to 1435.degree. C. Firing schedules vary according the raw material combination.

Abstract: High magnesium-content magnesium aluminosilicate glasses are used to form green tape compositions that are fired stepwise, i.e., first to about 500.degree. C. to remove organic materials, then to a temperature 10-30.degree. C. above the glass transition temperature for a time sufficient to nucleate the glass, and finally to a higher temperature near but below the softening temperature to complete crystallization of the glass. The resultant glass-ceramic may include substantial amounts of the forsterite crystalline phase. Multilayer ceramic printed circuit boards are made that are useful for high frequency, microwave applications. The fired high magnesium oxide content glasses have low dielectric constant and low dissipation loss factors, and they have a thermal coefficient of expansion that is compatible with metal or ceramic support substrates that impart mechanical strength to the printed circuit boards and that are thermally conductive. The boards are compatible with gallium arsenide devices.

Abstract: Disclosed are a low-temperature sinterable ceramic composition comprising 100 parts by weight of an essential component composed of from about 60 to 85% by weight of cordierite and from about 15 to 40% by weight of glass, and not larger than about 25 parts by weight of TiO.sub.2, and a monolithic ceramic substrate comprising the composition. The composition can be sintered at relatively low temperatures, and the sintered substrate has a small thermal expansion coefficient and a small dielectric constant. The temperature-dependent variation in the electrostatic capacity of the substrate is small. Preferably, the glass component in the composition is composed of about 20 to 60% by weight of SiO.sub.2, about 30 to 50% by weight of B.sub.2 O.sub.3, about 5 to 30% by weight of MgO, 0 to about 15% by weight of Al.sub.2 O.sub.3, and about 1 to 5% by weight of R.sub.2 O in which R is an alkali metal.

Abstract: High magnesium-content magnesium aluminosilicate glasses are used to form green tape compositions that are fired stepwise, i.e., first to about 500.degree. C. to remove organic materials, then to a temperature 10-30.degree. C. above the glass transition temperature for a time sufficient to nucleate the glass, and finally to a higher temperature near but below the softening temperature to complete crystallization of the glass. The resultant glass-ceramic may include substantial amounts of the forsterite crystalline phase. Multilayer ceramic printed circuit boards are made that are useful for high frequency, microwave applications. The fired high magnesium oxide content glasses have low dielectric constant and low dissipation loss factors, and they have a thermal coefficient of expansion that is compatible with metal or ceramic support substrates that impart mechanical strength to the printed circuit boards and that are thermally conductive. The boards are compatible with gallium arsenide devices.

Abstract: Multilayer green tape stacks having sufficient layers so that the fired stack is at least 2 millimeters in thickness on a metal support substrate are made by interleaving two types of green tapes comprising a low dielectric loss glass of a first type including at least 5% of an oxide filler and a green tape of a second type comprising a low dielectric loss glass and a higher amount of an oxide filler than the green tape of the first type, on a metal support substrate. These fired green tape stacks shrink on firing only in the thickness dimension.

Abstract: A ceramic honeycomb catalyst having an excellent thermal shock resistance in which a carrier is coated on a ceramic honeycomb structural body, has a mean thermal expansion coefficient in a range from 40.degree. to 800.degree. C. of smaller than 0.7.times.10.sup.-6 /.degree.C. Therefore, it is possible to obtain a ceramic honeycomb catalyst having excellent thermal shock resistance in which a mechanical strength of a ceramic honeycomb structural body to which a carrier such as .gamma.-alumina is coated is not decreased and the carrier is not peeled off from the ceramic honeycomb structural body.

Abstract: Multiphase ceramic materials for use in multilayered device fabrication may be fabricated by providing novel glassy precursor materials of a preferred composition, with operable amounts of a non-glassy filler materials. The combined materials are fired at appropriate temperatures, so that a non-glassy anorthite type phase is formed. Material so fabricated is formed in a self-limiting process, in that reaction between the glassy precursor material and the non-glass filler material is terminated when one constituent of the glassy precursor material is fully consumed. The materials of the instant invention, fabricated according to the method disclosed herein, demonstrate excellent dielectric constant, and electrical loss characteristics.

Abstract: A crystallizable ceramic composition for forming a ceramic dielectric body having a dielectric constant in the range of 4.8-5.3 at 1 MHz and a linear thermal expansion coefficient of 4.0-5.1.times.10.sup.-6 K.sup.-1 in the temperature range of 25.degree.-200.degree. C. The dielectric composition comprises a mixture of finely divided particles of 10-90 wt % Mg-Al-Si glass and 10-90 wt % Ca-Al-B-Si glass. The dielectric composition can be used with organic solvents, polymeric binder and plasticizer to produce an unfired green tape which is cofirable with high electrical conductivity metallurgies such as gold, silver, silver-palladium and copper.

Abstract: This invention is directed at the makings of glass-ceramic which is uniquely suited for use as a disc substrate for utilization in a magnetic memory storage device. The glass ceramic material exhibits a crystal phase assemblage comprised predominately of a mixture of lithium disilicate and tridymite which are uniformly interspersed with a residual glass phase and form an interlocked microstructure with the glass. The composition consists essentially, expressed in terms of weight percent on the oxide basis, of 75-95% SiO.sub.2, 3-15% Li.sub.2 O, 0-6% Al.sub.2 O.sub.3, and 0-6% K.sub.2 O. The nucleating agent for this glass-ceramic is selected from the group consisting of 0-0.1% Pd and 0-5% P.sub.2 O.sub.5 ; however if Pd is absent the P.sub.2 O.sub.5 amount is at least 0.5% and if P.sub.2 O.sub.5 is absent then the Pd amount is at least 0.005%. Additionally, up to 15% of optional ingredients may be added, including, B.sub.2 O.sub.3, Na.sub.2 O, ZnO, MgO, CaO, SrO, ZrO.sub.2, TiO.sub.2, F, Sb.sub.2 O.sub.3, As.

Abstract: A glass-ceramic magnetic disk substrate which is prepared by forming, then heat treating, and then polishing a crystallizable glass composition comprising, expressed in terms of weight percent on the oxide basis: from 20 to 45% SiO.sub.2 ; from 25 to 45% Al.sub.2 O.sub.3 ; from 10 to 25% B.sub.2 O.sub.3 ; from 2 to 12% MgO; from 0.5 to 8% TiO.sub.2 ; from 0.5 to 5% P.sub.2 O.sub.5 ; from 0 to 2% Li.sub.2 O; from 0 to 2% Na.sub.2 O; from 0 to 3% K.sub.2 O; wherein, the total of the contents of Li.sub.2 O, Na.sub.2 O and K.sub.2 O is from 0 to 5%; and wherein the magnetic disk substrate comprises a main crystalline phase consisting of at least one member selected from the group consisting of mullite and aluminum borate crystals. The glass composition can easily be formed and the disk substrate can easily be polished, has excellent mechanical strength, surface flatness, surface smoothness, chemical durability, and heat resistance, and shows no deterioration of magnetic film characteristics by alkali migration.

Abstract: A coatable insulator composition for use in the formation of a green tape comprising fine inorganic micropowders composed of amorphous glass and a refractory oxide in a volatile organic solvent solution of a binder composed of a polymer substance and a plasticizer(s). A green tape obtained by coating said composition over a flexible substrate, and heating and drying this product to remove the organic solvent; and a method for forming a barrier-rib for a plasma display apparatus by sandblast etching using said green tape as an insulator layer for the barrier-rib formation. A use of a pre-formed green tape of uniform thickness in the formation of the barrier-rib of a plasma display apparatus allows the thickness uniformity of the barrier-rib to be improved and the work rationalized, which means that the plasma display apparatus can be made larger and finer, and mass production throughput will be enhanced.

Abstract: A glass-ceramic sintered body comprising an SiO.sub.2 --Al.sub.2 O.sub.3 --MgO--ZnO--B.sub.2 O.sub.3 type crystalline glass and alumina, said sintered body containing at least 10% by weight of a spinel crystalline phase; and a substrate composed of the sintered material. There is also provided a process for producing the glass-ceramic sintered body which comprises adding a binder to a mixed powder of an SiO.sub.2 --Al.sub.2 O.sub.3 --MgO--ZnO--B.sub.2 O.sub.3 type crystalline glass and alumina, molding the mixture into a predetermined shape, and firing the mixture into a predetermined shape, and firing the molded mixture at a temperature of 925.degree. to 1000.degree. C. in a non-oxidizable atmosphere. The glass-ceramic sintered body and the substrate composed of it in accordance with the present invention have excellent mechanical strength and thereby have markedly increased metallizing adhesion strength.

Abstract: The invention relates to fiber reinforced composite materials, and a method for making, in which ceramic, glass-ceramic or glass matrix precursor particles are coated with a layer of sheet silicate crystals, or precursors for sheet silicate crystals, and then combined with a fiber reinforcement phase disposed within the matrix consisting of amorphous or crystalline inorganic fibers. The method results in a composite material in which a substantially continuous layer of sheet silicate is provided on the matrix particles, resulting in a substantially continuous sheet silicate interface between the inorganic fibers and the ceramic, glass or glass-ceramic matrix.

Abstract: A low thermal expansion cordierite aggregate, which consists mainly of cordierite crystals having a mean crystal diameter of at least 50 .mu.m and has little orientation in the crystal structure, shows hysteresis in its thermal expansion property accompanying a rise and fall of the temperature, and has a mean thermal expansion coefficient within a temperature range of from room temperature to 1000.degree. C. of at most 10.times.10.sup.-7 /.degree.C.

Abstract: This invention is directed to the fabrication of SiC fiber reinforced, ceramic matrix composite articles exhibiting superior high temperature oxidative stability, those articles comprising:(a) a glass-ceramic matrix wherein alkali metal and/or alkaline earth metal aluminosilicate crystals constitute the predominant crystal phase;(b) a fiber reinforcing phase comprising SiC fibers coated with an alkali metal and/or alkaline earth metal sheet silicate entrained within said glass-ceramic matrix; and(c) a borosilicate glass phase dispersed as an intergranular glass within said glass-ceramic matrix, said borosilicate glass phase generally being present in an amount sufficient to provide an intergranular glass phase therein.

Abstract: A composition and process are disclosed for constructing a diesel engine element, such as for example, a valve guide which will withstand the friction of various tribological locations in a diesel engine when operating the engine at elevated temperatures and/or on alternative fuels. The composition is one of a glass,glass-ceramic, and mixtures thereof matrix having graphite particles. In the process, a unitary element is formed from the mixture and thereafter is sintered for a time and temperature sufficient to obtain a preselected density.

Abstract: A composition and process are disclosed for constructing a diesel engine element, such as for example, a valve guide which will withstand the friction of various tribological locations in a diesel engine when operating the engine at elevated temperatures and/or on alternative fuels. The composition is one of a glass,glass-ceramic, and mixtures thereof matrix having graphite particles. In the process, a unitary element is formed from the mixture and thereafter is sintered for a time and temperature sufficient to obtain a preselected density.

Abstract: A dielectric ceramic body prepared by firing a mixture of a cordierite glass powder and a TiO.sub.2 powder, or a mixture of these powders and a RE.sub.2 Ti.sub.2 O.sub.7 powder (RE representing a rare earth element), wherein particles of the TiO.sub.2 powder or particles of the TiO.sub.2 powder and the RE.sub.2 Ti.sub.2 O.sub.7 powder are dispersed in a matrix phase of crystalline cordierite produced from the fired cordierite glass powder. In the first case, the cordierite glass powder and the TiO.sub.2 powder have a proportion which satisfies 70.ltoreq.x<100, 0<y.ltoreq.30, and x+y=100, where x and y represent contents in weight % of the cordierite glass powder and said TiO.sub.2 powder, respectively. In the second case, the cordierite glass powder, TiO.sub.2 powder and the RE.sub.2 Ti.sub.2 O.sub.7 powder have a proportion which satisfies 50.ltoreq.x<100, 0<y.ltoreq.30, 0<z.ltoreq.40, and x+y=100, where z represents a content in weight % of the RE.sub.2 Ti.sub.2 O.sub.7 powder.

Abstract: A low thermal expansion cordierite aggregate, which consists mainly of cordierite crystals having a mean crystal diameter of at least 50 .mu.m and has little orientation in the crystal structure, shows hysteresis in its thermal expansion property accompanying a rise and fall of the temperature, and has a mean thermal expansion coefficient within a temperature range of from room temperature to 1000.degree. C. of at most 10.times.10.sup.-7 /.degree.C.

Abstract: A cordierite glass-ceramic having a cordierite crystal phase as a predominant crystal phase is obtained by melting a base glass consisting in weight percent of:______________________________________ SiO.sub.2 38-50% Al.sub.2 O.sub.3 18-30% MgO 10-20% ______________________________________the ratio in weight of Al.sub.2 O.sub.3 to MgO being 1.2 to 2.3 ______________________________________ B.sub.2 O.sub.3 0-5% CaO 0-5% BaO 0-5% SrO 0-5% ZnO 0.5-7.5% TiO.sub.2 4-15% ZrO.sub.2 0-5% As.sub.2 O.sub.3 + Sb.sub.2 O.sub.3 0-2% ______________________________________and forming the glass and subjecting the glass to heat treatment. This glass-ceramic is suitable for use as a high strength material reqiring high resistivity to heat and impact and as materials requiring a fine processing or a precision processing such as electronic parts, magnetic disk substrates and machine parts.

Abstract: A ceramics binder mixture having from 4.3 to 7 parts by weight, as calculated as silica, of a silica-sol mixed to 100 parts by weight of a mixture comprising (1) from 25 to 60 parts by weight of cordierite aggregates prepared by melting and vitrifying a mixture of an approximate cordierite composition (2MgO.2Al.sub.2 O.sub.3.5%SiO.sub.2), followed by crystallization to cordierite, and having a particle size of from 0.1 to 1 mm, (2) from 6 to 17 parts by weight of a fine powder of silica having particle sizes of from 0.1 to 10 .mu.m, and (3) the rest being a powder composed mostly of cordierite particles and having particle sizes smaller than 0.1 mm, whereby the Na.sub.2 O content in the binder mixture excluding moisture is not higher than 0.3 wt %.

Abstract: The ceramic substrate comprising a glass and a crystal is characterized by the glass comprising a MgO--Al.sub.2 O.sub.3 --SiO.sub.2 --B.sub.2 O.sub.3 --R.sub.2 O-base glass(R:alkali metal) and containing a 2MgO.2Al.sub.2 O.sub.3.5SiO.sub.2 crystal (cordierire) as the crystal. Due to the composition, the softening point of the glass becomes less than 720.degree. C. and the porosity decreases, so that the substrate can be dense. As a result, the coefficient of thermal expansion thereof can be close to silicon, the specific inductive capacity thereof can be small and the substrate can be excellent in transverse strength, moisture resistance, water resistance, etc. And, due to the lowered softening point, a ceramic substrate having the above characteristics can be produced even by sintering at between 800.degree. C. and 1000.degree. C., and ceramic substrate having an inner circuit interconnection made of Ag or Cu, etc. can be produced.

Abstract: Novel oxide coatings which can be conveniently applied to reinforcing fibers such as silicon carbide fibers, and which when introduced as a fiber coating into fiber reinforced ceramic matrix composites provide composites exhibiting improved resistance to embrittlement at high temperatures, are described. Oxides effective to provide the improved composites in accordance with the invention include CeO.sub.2 and ZrO.sub.2.

Abstract: The invention provides a glass-ceramic composite with sufficient strength and other excellent properties suitable for IC packages or multilayer substrates. The glass-ceramic composite of the invention includes crystallized glass and at least either of alumina and mullite at the ratio by weight of eighty through fifty-five to twenty through forty-five. The crystallized glass includes cordierite as primary crystals and contains 40 to 52 percent by weight of silicon dioxide or SiO.sub.2, 27 to 37 percent by weight of aluminum oxide or Al.sub.2 O.sub.3, 11 to 13 percent by weight of magnesium oxide or MgO, 2 to 8 percent by weight of diboron trioxides or B.sub.2 O.sub.3, 2 to 8 percent by weight of calcium oxide or CaO, and 0.1 to 3 percent by weight of zirconium oxide or ZrO.sub.2.

Abstract: A composite substrate is provided, which comprises a cordierite-anorthite-boron base composite material and has a microstructure with anorthite included in the cordierite phase. This substrate can be used in the form of a circuit substrate, because it has high-enough mechanical strength, a coefficient of thermal expansion close to that of silicon and a decreased dielectric constant and, moreover, can be sintered at a low temperature.

Abstract: The invention provides a glass-ceramic composite with sufficient strength and other excellent properties suitable for IC packages or multilayer substrates. The glass-ceramic composite of the invention includes crystallized glass and at least either of alumina and mullite at the ratio by weight of eighty through fifty-five to twenty through forty-five. The crystallized glass includes cordierite as primary crystals and contains 40 to 52 percent by weight of silicon dioxide or SiO.sub.2, 27 to 37 percent by weight of aluminum oxide or Al.sub.2 O.sub.3, 11 to 13 percent by weight of magnesium oxide or MgO, 2 to 8 percent by weight of diboron trioxides or B.sub.2 O.sub.3, 2 to 8 percent by weight of calcium oxide or CaO, and 0.1 to 3 percent by weight of zirconium oxide or ZrO.sub.2.

Abstract: A plastically deformable mixture and method for making a body from the mixture are disclosed. The mixture is composed of powder materials, which when fired form as predominant phases: ceramic, glass-ceramic, glass, and combinations thereof, 0 to an effective amount of burnout agent, water, organic binder which can be cellulose ether, cellulose ether derivatives or combinations thereof, and hydrophilic and hydrophobic additives, to increase the wettability and/or lubricity of the mixture. One advantageous composition for ram extrusion is composed of ceramic-forming powders, water, and in percent by weight based on the powders, about 2% to 8% organic binder which can be methylcellulose, methylcellulose derivatives, and combinations thereof, about 0.3% to 1.0% sodium stearate, and about 0.5% to 2.0% oleic acid.

Abstract: A ceramics composite material containing crystallized glass as the matrix and fibers or whiskers of ceramics as a reinforcement material, is obtained by melting original glass to form crystallized glass, compounding the same with fibers or whiskers of oxide ceramics and thereafter crystallizing the original glass. This ceramics composite material does not form any voids and can easily contain at least 50 volume percent of the reinforcement material, whereby a good mechanical strength and fracture toughness are achieved. In the compounding step, the content of the reinforcement can be further increased by forcing out any excess part of the original glass from the reinforcement material by applying pressure to a substance obtained by mixing the original glass with the reinforcement. Further, the ceramics composite material can be efficiently formed into a desired configuration by heating because the original glass flows viscously.

Abstract: A sintering process is described using a glass-ceramic slurry containing an alloy powder or flakes selected from a group of alloys consisting of:______________________________________ Fe--Cr Cu--Ti Fe--Cr--Ni Ag--Ti Cr--Al Nb--Al Ni--Cr Cu--Al Ni--Al Cu--Al--Cr Fe--Al ______________________________________The slurry is molded and later is sintered in a steam atmosphere at a temperature of about 1000.degree. C. to yield a glass-ceramic substrate toughened against crack propagation and useful in the packaging of semi-conductor device chips.

Abstract: Cordierite-forming green substrates having high wet strength are prepared from fine-particle size minerals, including about 5 to 30 weight percent of delaminated kaolin and, preferably, about 15 to 39 weight percent calcined kaolin. The other fine-particle size minerals utilized are preferably talc having a particle diameter of about seven microns or less and alumina having a particle diameter of about one micron or less.

Abstract: Fiber-reinforced glass-ceramic matrix composites exhibiting substantially increased resistance to stress failure above the microcrack point in a hot oxidizing environment are provided by introducing into the composite a matrix additive consisting of a stable, refractory, chemically compatible glass. The glass is disposed as an intergranular glass phase in the crystalline aluminosilicate glass-ceramic matrix of the composite, which may further comprise a whisker addition to the matrix to increase the high-temperature viscosity of the intergranular glass.

Abstract: A process for producing dense-sintered cordierite bodies and zirconium dioxide-reinforced cordierite bodies with a maximum of 50% by weight of ZrO.sub.2 is described, wherein a powder of cordierite particles of stoichiometric composition and, if appropriate, ZrO.sub.2 of a particle size of less than 3 .mu.m is heated at temperatures above 800.degree. C. at a rate of temperature rise of less than 5.degree. C. per minute. Virtually pore-free sintered bodies having outstanding mechanical properties can be produced by the process.

Abstract: A ceramic composite body which includes high purity amorphous silica fibers in a ceramic matrix. The ceramic matrix may be a glass ceramic material, a borosilicate glass material or mixtures thereof.

Abstract: A glass powder crystallizable to yield a sintered glass ceramic containing hexagonal cordierite as the principal crystal phase is of the composition, in mol % on an oxide basis, of 48-61 SiO.sub.2 ; 10-16 Al.sub.2 O.sub.3 ; 23-35 MgO; 0-4 B.sub.2 O.sub.3 ; 0-2.5 P.sub.2 O.sub.5 ; 0.5-5 .SIGMA. B.sub.2 O.sub.3 +P.sub.2 O.sub.5 ; 0-3 ZnO; 0-3 CaO; 0-1.5 BaO and as an essential component 0.5-12 F as a substitute for O. The glass powder may also contain a total of up to 3 mol % of one or more of the oxides PbO, SrO and SnO.sub.2. The glass powder can be crystallized at sintering temperatures below 970.degree. C. in a relatively broad sintering temperature range to yield a sintered glass ceramic having excellent and constant properties. It is particularly suitable for the production of electrotechnical and electronic components since it has very good electrical, dielectrical and mechanical properties.

Abstract: In the process according to the invention, a gel is prepared by hydrolysis and polycondensation of precursor compounds which comprise at least silicon alcoholate and aluminum alcoholate and inorganic compounds of lithium and/or magnesium, the solvent is removed, and the gel obtained is subjected to a heat treatment resulting in dehydration and oxidation, then to compacting and ceramisization.The composition obtained is substantially in the form of solid ceramic solutions, such as .beta.-spodumene, cordierite and mullite.