Abstract: This invention relates to a torch comprising:a) a nozzle having a bore extending therethrough, the bore comprising a first end portion, a second end portion, and an arcuate middle portion defining an arcuate tube surface,b) means for providing a flame flowing from the first end portion of the bore towards the second end portion of the bore, so that the flame impinges upon the arcuate tube surface,wherein the arcuate tube surface comprises silicon carbide.

Abstract: A modular igniter system which preferably provides either direct electrical connection between the metallized ends of the hot surface igniter and the socket contact, or indirect electrical connection by a short lead wire held in place on the hot surface element by an active metal braze.

Abstract: A ceramic igniter comprisesa pair of conductive ends,a hot zone disposed between the conductive ends, the hot zone having a density of at least about 95% of theoretical density and a composition comprising:(a) between about 50 and about 80 vol % of an electrically insulating material selected from the group consisting of aluminum nitride, boron nitride, silicon nitride, and mixtures thereof.(b) between about 10 and about 45 vol % of a semiconductive material selected from the group consisting of silicon carbide and boron carbide, and(c) between about 5 and about 25 vol % of a metallic conductor selected from the group consisting of molybdenum disilicide, tungsten disilicide, titanium nitride, and mixtures thereof, anda support upon which the hot zone is disposed, wherein at least a portion of the hot zone has a thickness of no more than 0.019".

Abstract: A method for forming thin green ceramic igniter shapes having a thickness characterized by a tolerance of no more than about +/-0.001 inch includes providing an apparatus having a porous mold having a well which defines a pair of opposing porous walls, and a plurality of vertical dividers positioned in the well in substantially parallel, substantially spaced relation where each divider contacting each opposing wall to define a plurality of compartments. A ceramic slip formed from a ceramic powder and a liquid carrier is poured into the compartments of the apparatus, dewatered through the opposing porous walls to form a plurality of green ceramic igniter shapes. The plurality of green ceramic igniter shapes are removed from the plurality of compartments.

Abstract: A ceramic igniter comprising:a) a pair of electrically conductive portions, each portion having a first end,b) a hot zone disposed between and in electrical connection with each of the first ends of the electrically conductive portions, the hot zone having an electrical path length of less than 0.5 cm, andc) an electrically non-conductive heat sink material contacting the hot zone.

Abstract: This invention relates to an apparatus comprising:a) a article having a composition selected from the group consisting of graphite, carbon/carbon, carbon/graphite, and mixtures thereof, andb) a ceramic coating thereon, wherein the ceramic coating comprises a material selected from the group consisting of:i) a ceramic having an average thermal expansion coefficient of between 2 and 8.times.10.sup.-6 /.degree. C. between 22.degree. C. and 1200.degree. C. which is also phase stable in the temperature range of 22.degree. C. and 1450.degree. C., andii) alumina having at least 99% purity.

Abstract: This invention relates to hot pressed silicon carbide dummy wafers having low iron impurity levels, and a method of using hot pressed silicon carbide dummy wafers in silicon wafer processing applications.

Abstract: A ceramic body comprising at least about 80 w/o silicon nitride and having a mean tensile strength of at least about 800 MPa.

Abstract: This invention relates to a Hall-Heroult cell for aluminum production comprising a cryolite-resistant liner comprising:i) between 75 weight percent wt % and 95 wt % alumina-silica refractory grain, andii) between 1 wt % and 10 wt % of a sealant selected from the group consisting of feldspar and nepheline.

Abstract: Substrates are disclosed having an ultra-smooth surface finish thereon rendering them useful in making high density magnetic storage components, such as a computer hard disk or thin-film head which can read and/or write data on such disks. The substrates are comprised of a non-oxide ceramic base which is coated with a smoothing layer comprised of amorphous, non-stoichiometric silicon carbide corresponding to the formula SiC.sub.x, wherein x is the molar ratio of carbon to silicon and is greater than 1. Also disclosed are processes for making the substrates and components.

Abstract: The present invention relates to a refractory shield for protecting a superheater tube against fluid attack comprising first and second partial-tubes, each partial-tube having a C-shaped cross-section, the C-shaped cross section defining first and second ends; wherein the ends of the partial-tubes are opposably engaged, and wherein the partial-tubes comprise means for preventing radial movement of the first partial-tube relative to the second partial-tube.

Abstract: A process for analyzing analytes using nebulizer component selected from the group consisting of a desolvation tube, a condenser tube, an aerosol-generator and a transducer, wherein the component has a contact surface selected from the group consisting of CVD silicon carbide, CVD diamond film and glassy carbon.

Abstract: A ceramic igniter comprising: a) a lead wire, b) a ceramic substrate, and c) a braze pad having a thickness of less than about 150 microns, wherein the lead wire and ceramic substrate are placed in electrical connection by the braze pad.

Abstract: This invention relates to a method for producing a crack-free sintered silicon carbide body, comprising the steps of:a) providing a raw powder batch comprising:i) at least 40 w/o fine grain fraction having a particle size of less than 10 microns, the fine grain fraction comprising silicon carbide,ii) at least 40 w/o coarse grain fraction having a particle size of at least 30 microns, the coarse grain fraction comprising silicon carbide and less than 0.10 w/o free carbon,the raw batch having a total silica content of at least 0.5 w/o,the raw batch having a total silicon carbide content of at least 96 w/o,b) forming the raw batch into a green body, andc) recrystallizing the green body to provide a recrystallized silicon carbide body having a density of between 2.0 g/cc and 2.8 g/cc.

Abstract: This invention is related to a flowable slurry comprising between 79 and 86 w/o silicon nitride solids.

Abstract: The present invention relates to novel alumina-based ceramic composition containing a compound capable of forming a spinel-type aluminate phase detectable by x-ray diffraction, the composition having particular advantage for use as a water faucet seal.

Abstract: A ceramic composition for sintering into sliding parts contains:at least 90% by weight alumina,1.7% by weight to 2% by weight Mn.sub.3 O.sub.4,0.8% by weight to 1% by weight TiO.sub.2,0.5% by weight to 1.5% by weight SiO.sub.2,0.6% by weight to 1.2% by weight CoO,not more than 1% by weight MgO,not more than 0.4% by weight Fe.sub.2 O.sub.3,the remainder, up to 0.5% in total, comprising impurities.After sintering, this composition produces sliding parts containing manganese aluminate and/or cobalt aluminate phases.

Abstract: The invention includes a process for producing a reaction bonded silicon carbide composite reinforced with coated silicon carbide fibers which is suitable for high temperature applications. The process includes the steps of coating SiC fibers with AlN, BN or TiB.sub.2 ; treating the coated fibers with a mixture of SiC powder, water and a surfactant; preparing a slurry comprising SiC powder and water; infiltrating the coated fibers with the slurry to form a cast; drying the cast to form a green body; and reaction bonding the green body to form a dense SiC fiber reinforced reaction bonded matrix composite.The invention further includes a SiC fiber reinforced SiC composite comprising a reaction bonded SiC matrix, a SiC fiber reinforcement possessing thermal stability at high temperatures and an interface coating on the fibers having chemical and mechanical compatibility with the SiC matrix and with the SiC fibers.

Abstract: Silicon carbide sintered bodies having controlled porosity in the range of about 2 to 12 vol %. in which the pores are generally spherical and about 50 to 500 microns in diameter, are prepared from raw batches containing a polymer fugitive. Sintered bodies in the form of mechanical seal members exhibit lower power consumption at low PV and, in addition, lower wear rates at high PV in comparison to commercially available silicon carbide seal members.

Abstract: Layered substrates are disclosed having an ultra-smooth surface finish thereon rendering them useful in making high density magnetic storage media. The layered substrates are comprised of a non-oxide ceramic core coated with a smoothing layer comprised of an amorphous metal, particularly certain amorphous metal alloys based on chromium, molybdenum, tungsten, and mixtures thereof. Also disclosed are magnetic storage media comprising the layered substrates, as well as processes for making the substrates and magnetic media.