Abstract: Uniform sialon powders having a sharp particle size distribution are obtained by mixing (i) amorphous silicon nitride powders, (ii) an oxygen-containing compound of silicon or/and aluminum, and (iii) aluminum metal, aluminum nitride and/or silicon, and then heating the resultant mixture at 1300.degree. to 1800.degree. C. in an atmosphere containing nitrogen.

Abstract: A blended, stable ball clay/water slurry, wherein:1. the slurry comprises from about 58 to about 68 weight percent of ball clay, from about 42 to about 32 weight percent of water, from about 50 to about 650 parts per million (by dry weight of ball clay) of soluble sulfate ion, and from about 0.01 to about 1.0 percent of organic polyelectrolyte (weight of active ingredient by weight of dry ball clay) with a molecular weight of from about 1400 to about 6000;2. the slurry, when freshly made has a five-minute gel viscosity of from about 1,000 to about 10,000 centipoise, a ten-minute gel viscosity of from about 2,200 to about 12,000 centipoise, and a twenty-minute gel viscosity of from about 3,500 to about 14,000 centipoise.

Abstract: At least two different ball clay/water mixtures are blended together to produce a ball clay/water slurry, wherein:1. the slurry comprises from about 58 to about 68 weight percent of ball clay, from about 42 to about 32 weight percent of water, from about 50 to about 650 parts per million (by dry weight of ball clay) of soluble sulfate ion, and from about 0.01 to about 1.0 percent of organic polyelectrolyte (weight of active ingredient by weight of dry ball clay) with a molecular weight of from about 1400 to about 6000;2. the slurry, when freshly made has a five-minute gel viscosity of from about 1,000 to about 10,000 centipose, a ten-minute gel viscosity of from about 2,200 to about 12,000 centipoise, and a twenty-minute gel viscosity of from about 3,500 to about 14,000 centipoise.

Abstract: An aluminum nitride ceramic body with a thermal conductivity of at least 0.5 W/cm.multidot.K at 25.degree. C. is produced by shaping a particulate mixture of aluminum nitride powder and an additive selected from the group consisting of YF.sub.3, ScF.sub.3, LF.sub.3 where L is La, Ce, Pr, Nd, Sm, Gd, Dy, Ho and Er and a mixture thereof into a compact and liquid phase sintering the compact.

Abstract: The invention relates to an admixture to be used in preparing a fresh concrete with enhanced flowability and air-entraining property.

Abstract: A building material plate formed by compression in the hydration-water moist state and having quality features resembling asbestos-reinforced cement and made of an asbestos-free material mixture having up to 30 vol. % of cellulose fiber proportions in the high-packed state of a diameter spectrum D.sub.C, singly bound into a hydration binder particle mixture still present in the moist forming state of a grain size-main distribution spectrum D.sub.o within the ratio range0.9.ltoreq.D.sub.C /D.sub.o .ltoreq.1.1,which in case of a participation of cement in the binder contains special additives showing a pozzuolana reaction for securing constancy in longterm quality.

Abstract: The present invention is characterized by ceramic materials comprising ceramic sintered bodies consisting of (1) 1-90 wt % chromium carbide and the remainder carbonic titanium nitride; (2) 1-90 wt % chromium carbide, 0.1-5 wt % B.sub.4 C and the remainder titanium carbo-nitride; or (3) either of the above compositions plus less than 95 wt % of a metal boride such as Ti or Zr. Such ceramic sintered bodies are used for cutting tools or wear-resistant machine parts because of their high density, high hardness and high strength.

Abstract: A method of producing self-supporting ceramic structures comprising (i) a polycrystalline oxidation reaction product formed upon oxidation of a body of molten parent metal with an oxidant, and (ii) interconnected porosity at least partially accessible from one or more surfaces of said ceramic body. A second polycrystalline ceramic material is incorporated into the porosity of said ceramic body to modify or contribute to its properties.

Abstract: A ceramic material which comprises a composite of zirconia and O'-sialon or silicon oxynitride.The ceramic material may comprise a dispersion of zirconia in an O'-sialon matrix and such a dispersion is obtained when the amount of zirconia is from 5 to 30 volume percent, preferably 15 to 25 volume percent, based on the total volume of the composition.

Abstract: The invention is generally accomplished by forming a three-dimensionally shaped, externally worn feminine protection device which has been mechanically shaped by folding, molding or other forming techniques in such a way that it has a raised portion located within the back one-half to two-thirds of the device that functions to cause the pad to readily fit to and generally align itself within the inverted V-shaped regions of the woman's lower abdominal region, vulva, perineum and the anterior portion between the buttocks. The forward portion of the device of the invention generally is flattened in use to cover externally the area of the pubic mons and the area exterior of the clitoris. The back portion of the device is formed in a peak like shape which readily adjusts to and molds to the inverted V-shape of the rear portion of the labia, the perineum and the forward portion of the area between the buttocks.

Abstract: The invention is a molded body of polycrystalline aluminum nitride having a density of at least 99.8% TD and comprising:at least 99% by weight AlNup to 0.35% by weight residual oxygenup to 0.35% by weight residual carbon andup to 0.03% by weight metallic impurities (Fe, Si, Ca, Mg).In the molded body, the aluminum nitride is present in the form of a single phase, homogeneous, isotropic microstructure having a maximum grain size of 5 .mu.m. The residual oxygen and the residual carbon are present in the form of a solid solution in the aluminum nitride lattice and caromografically not detectable as separate phase(s) up to a magnification of 2400 times. The molded bodies have a bending strength measured according to the 4-point method, at room temperature and up to about 1400.degree. C., of at least 500 N/mm.sup.2, a predominantly transcrystalline rupture modulus and a thermal conductivity at 300 K of at least 150 W/mK.

Abstract: Refractory fibers comprising a homogeneous mixture of 60 to 95 weight percent amorphous alumina and 40 to 5 weight percent amorphous phosphorus pentoxide. The fibers optionally can contain chloride, and up to 20 weight percent carbon derived from the alumina precursor material. Other organic residues can be present. The fibers are useful in the manufacture of fireproof consumer fabrics as well as reinforcement or polymeric composites.

Abstract: The particulate solid is maintained in a bed in contact with a liquid within a high pressure vessel. The particulate solid is supported in the vessel in a cone-like configuration. A discharge tube is provided communicating with the particulate solid running from the bottom of the cone externally of said vessel and pressure on the supported particulate is produced to discharge said particulate out of said vessel via the discharge tube.

Abstract: A high-toughness ceramic tool material consisting essentially of 50-95% by volume of a main sialon base phase wherein at least 10% by volume of the sialon base phase consists of alpha-sialon, and 5-50% by volume of a SiC whisker phase. This ceramic material is produced by sintering a composition comprising:50-95% by volume of a sialon forming component such that at least 10% by volume, calculated on the entire sialon, of alpha-sialon is formed, and5-50% volume of SiC whiskers;said sialon forming component consisting essentially of 50-95% by weight of Si.sub.3 N.sub.4 and 50-50% by weight of constituents of sialon-consistituting elements other than Si.sub.3 N.sub.4,said constituents consisting of a mixture of AlN and Al.sub.2 O.sub.3, and at least one oxide selected from the group consisting of oxides of yttrium and rare earth elements, said mixture of AlN and Al.sub.2 O.sub.

Abstract: An improved process for producing a translucent polycrystalline alumina body comprising rapid-sintering a prefired compacted green body of alumina of predetermined shape is disclosed. The green body of alumina includes alumina doped with one or more sintering aids. Rapid sintering in accordance with the method of the present invention comprises the steps of raising the temperature of the prefired compacted green body of predetermined shape up to maximum sintering temperature at a heating rate greater than or equal to about 0.1.degree. C./second and less than the rate at which the green body experiences thermal shock; and heating the green body at the maximum sintering temperature for a period of time sufficient to produce a translucent polycrystalline alumina body. The rapid sintering is carried out under a flowing gas mixture of nitrogen and at least about 2.5 volume percent hydrogen.

Abstract: A fine aggregate is stored in a high storage silo and its surface water content is so controlled that its variation may be kept within .+-.1% by weight. The fine aggregate, cement and primary water containing an air entraining agent are mixed in an upper mixer (primary mixing) to prepare mortar. The mortar, a coarse aggregate and secondary water containing a water reducing agent are mixed in a lower mixer (secondary mixing) to produce mixed concrete.

Abstract: An electrically conductive hot press sintered ceramic product comprising boron nitride, titanium diboride and aluminum nitride and having a flexural strength of at least 900 kg/cm.sup.2, a specific resistance of from 300 to less than 2,500 .mu..OMEGA.cm and less anisotropy.

Abstract: A dielectric ceramic composition for high frequencies consisting essentially of a basic composition expressed by the general formula:xMgO--yAl.sub.2 O.sub.3 --zSiO.sub.2wherein x, y and z are mole percentage of the respective components, x+y+z=100, 65.ltoreq.x.ltoreq.77, 1.ltoreq.y.ltoreq.15, and 8.ltoreq.z.ltoreq.34 and an exclusive additive of 0.1 to 10.0 weight % of Li.sub.2 O. The basic composition has a set of x, y and z falling within an area defined by a polygon ABCD encompassed by the points A, B, C and D in FIG.

Abstract: A fine powder of stabilized zirconia a process for its preparation and application of the powder in ceramic compositions to obtain good mechanical, thermomechanical and electrical properties.A zirconia hydrate sol having a pH between 0.5 and 5 and containing elementary acicular crystals having dimensions of from about 10 to 500 .ANG. which are agglomerated into submicron aggregates of from abuot 100 to 5000 .ANG. in diameter is mixed with a solution of a stabilizing agent, preferably yttrium; the suspension is dried; the dried suspension is calcined at a temperature of from about 700.degree. C. to 1,300.degree. C. for preferably from about 30 minutes to 24 hours; and if needed, the powder obtained is milled.

Abstract: A traction aid for snow and ice covered surfaces and method of use are disclosed. The preferred traction aid composition for highways comprises about 90% by weight of between 1/4 inch and 30 mesh hard, crushed limestone and about 10% by weight of 6/30 mesh heat treated ground clay. The preferred composition for sidewalks comprises about 80% by weight 4/30 mesh hard, crushed limestone and about 20% by weight of 6/30 mesh heat treated ground clay.