Abstract: An intermetallic bonded diamond composite composition and methods of processing such a composition are provided by the present invention. The intermetallic bonded diamond composite composition preferably comprises a nickel aluminide (Ni.sub.3Al) binder and diamond particles dispersed within the nickel aluminide (Ni.sub.3Al) binder. Additionally, the composite composition has a processing temperature of at least about 1,200.degree. C. and is processed such that the diamond particles remain intact and are not converted to graphite or vaporized by the high-temperature process. Methods of forming the composite composition are also provided that generally comprise the steps of milling, pressing, and sintering the high-temperature intermetallic binder and diamond particles.

Abstract: An intermetallic bonded diamond composite composition and methods of processing such a composition are provided by the present invention. The intermetallic bonded diamond composite composition preferably comprises a nickel aluminide (Ni3Al) binder and diamond particles dispersed within the nickel aluminide (Ni3Al) binder. Additionally, the composite composition has a processing temperature of at least about 1,200° C. and is processed such that the diamond particles remain intact and are not converted to graphite or vaporized by the high-temperature process. Methods of forming the composite composition are also provided that generally comprise the steps of milling, pressing, and sintering the high-temperature intermetallic binder and diamond particles.

Abstract: An apparatus and method for high-temperature precision sintering applications are disclosed wherein a flowable bed of a refractory particulate material is used to support an article during sintering to minimize distortions caused by shrinkage.

Abstract: A method for producing a high solids content, low viscosity ceramic slurry composition comprises turbomilling a dispersion of a ceramic powder in a liquid to form a slurry having a viscosity less than 100 centipoise and a solids content equal to or greater than 48 volume percent.

Abstract: A method is disclosed for producing silicon nitride wherein the crystal morphology is controlled. The method involves heating a mixture consisting essentially of a chlorosilane and ammonia at a sufficient temperature for a sufficient time to produce a nitogen containing silane as an intermediate. The bulk density of the intermediate is controlled to less than about 0.1 g/cc to result in the silicon nitride having a crystal morphology which is essentially all fibrous, or the bulk density can be controlled to greater than about 0.3 g/cc to result in the silicon nitride having a crystal morphology which is essentially all equiaxial, or the bulk density can be controlled to between about 0.1 g/cc and about 0.3 g/cc to result in the silicon nitride having a crystal morphology which is a mixture of fibrous and equiaxial. The intermediate is then heated at a sufficient temperature for a sufficient time in a non-oxidizing atmosphere to produce the controlled crystal morphology silicon nitride.

Abstract: A process is disclosed for producing beta silicon nitride fibers. The process involves heating a green article of a silicon nitride based material in a furnace at a temperature of from about 1700.degree. C. to about 2000.degree. C. at a pressure of nitrogen gas of at least about 100 psig for a sufficient time to form silicon nitride fibers, the major portion of which are beta silicon nitride fibers. The heating step is carried out with the article covered with a cover made of silicon carbide or silicon nitride. Alternately, the article can be in a container of silicon nitride or silicon carbide and covered with the cover.

Abstract: An article is disclosed comprising particles of a silicon nitride based material and a lubricating material, the lubricating material occupying interconnected spaces within the article, the spaces being at least about 3% by volume of the article.

Abstract: A silicon nitride based cutting tool is disclosed consisting essentially of in percent by weight about 5% aluminum oxide, about 6% yttrium oxide, from about 1.5% to about 5.5% silicon dioxide, and the balance silicon nitride, and having a density of at least about 99% of the theoretical density.

Abstract: Addition of from about 0.1 to about 6.0% by weight of V.sub.2 O.sub.5 to (PZT)lead zirconate-lead titanate powder promotes rapid densification at temperatures below 1000.degree. C. and eliminates the need for PbO atmosphere control. Densification to greater than 98% of theoretical density is achieved with firing times as short as 1-5 minutes. Dielectric properties depend upon the amount of V.sub.2 O.sub.5 added and upon the microstructure developed, but in general are equivalent to those reported for conventional PZT compositions.