Alliedsignal Inc.

Allied Corporation

Other

The Lummus Company

Honeywell International Inc.

Rutgers, the State University of New Jersey

Anthony J Fanelli

Joan V Burlew

Gary B Marsh

Mohammad Behi

Brian Jeffrey Snow

Ronald Paul Rohrbach

Abraham P Gelbein

Jean Yamanis

Michael S Zedalis

John N Armor

Alson K Price

Julie R Schollmeyer

Clifford P Ballard

Rick Duyckinck

Patrick M Zambri

Morgan C Sze

Harvey D Schindler

Jerry C LaSalle

John E Paustian

Arnulf J Maeland

Stephen Haig

Arthur T Walsh

Beili Li

Jeffrey P Solar

George Rak

Beili L Wu

William S Frei

Eoin Joseph Barry

Clifford Palmer Ballard, Jr

Richard Duyckinck

Robert W Armbrust

Robert D Silvers

Clifford Palmer Ballard

Molding compositions for shaping parts from stainless steel powders are disclosed. The process comprises the steps of forming a mixture comprising stainless steel powder, a gel-forming material having a gel strength, measured at a temperature between 0&deg; C. and about 30&deg; C. and a gel comprising about 1.5 wt % of the gel-forming material and water, of at least about 200 g/cm2, and water, and molding the mixture at a temperature sufficient to produce a self-supporting article comprising the powder and gel. The preferred gel-forming material is an agaroid and the preferred molding process is injection molding.

Stainless steel aqueous molding compositions

This invention provides a composition and a process for forming sintered, molded articles having improved dimensional stability. More particularly, this invention pertains to a composition having a sugar additive that increases the solids loading potential of the composition and a process for forming injection molded articles therefrom. Increasing the solids loading potential of the composition, enables the formation of metal or ceramic articles attaining about 98-99% of their theoretical maximum density, without cracking or shrinking significantly during sintering.

Aqueous injection molding binder composition and molding process

Recycled, reground ceramic powder is mixed with a liquid carrier, a binder and processing additives to form a material useful for molding complex-shaped parts at relatively low pressures in conventional injection molding equipment.

Process for forming an article from recycled ceramic molding compound

Molding compositions for shaping parts from stainless steel powders are disclosed. The process comprises the steps of forming a mixture comprising stainless steel powder, a gel-forming material having a gel strength, measured at a temperature between 0.degree. C. and about 30.degree. C. and a gel comprising about 1.5 wt % of the gel-forming material and water, of at least about 200 g/cm2, and water, and molding the mixture at a temperature sufficient to produce a self-supporting article comprising the powder and gel. The preferred gel-forming material is an agaroid and the preferred molding process is injection molding.

Process for making stainless steel aqueous molding compositions

A calcia mold facecoat is applied to a mold for casting parts composed of reactive metals such as titanium and titanium aluminide. The facecoat is composed of a calcium carbonate based slurry comprising a dense grain calcium carbonate powder and an aqueous based binder. It is applied to a wax or plastic pattern used in the lost wax process for fabricating a casting shell. The mold is built using multiple dipping of alumina-silicate slurries, and then fired at high temperatures in an oxygen rich environment. The metal part is cast before the fired mold can cool below about 800.degree. C. Organometallic based slurry binders are avoided and significant cost savings are realized owing to the benign nature of the aqueous based suspensions with respect to the environment.

Inert calcia facecoats for investment casting of titanium and

Parts from ceramic and/or metal powder(s) are shaped by a process that comprises the steps of (1) forming a mixture comprising ceramic and/or metal powder(s), a gel-forming material chosen from the class of polysaccharides known as 'agaroids', a gel-forming solvent, and a gel strength enhancing agent, and said mixture being formed in a blender that provides a shearing action and being heated to raise the temperature of the mixture to about 70.degree. C. to 100.degree. C.; and (2) molding the mixture at a temperature sufficient to produce a self-supporting structure comprising the powder and gel. The parts exhibit excellent green strength and are rapidly fired without cracking, distortion or shrinkage problems.

Gel strength enhancing additives for agaroid-based injection molding

A gel-forming composition is used in a process for molding a ceramic composition. The gel-forming composition, such as agar, is improved with a gel-enhancing agent, e.g. polyethyleneimine. As a result, the gel-forming composition improves the ceramic molding process and/or the ceramic product formed therefrom.

Modified agar and process for preparing modified agar for use ceramic

This invention provides a compound having the formula LnSi.sub.3 N.sub.5 wherein Ln is selected from the group consisting of scandium, yttrium, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. In addition, there is provided a method for making the compound Ln'Si.sub.3 N.sub.5 wherein Ln' is a radical selected from the group consisting of lanthanum, scandium, yttrium, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium, comprising the step of reacting SiO.sub.z, Ln'.sub.x O.sub.y in a nitrogen atmosphere in the presence of carbon at a temperature of from 1200.degree. C. to about 2000.degree. C. for at least 2 hrs., x being an integer equal to or greater than 2, y being an integer equal to or greater than 3, and z being an integer selected from 1 and 2, with the proviso that x and y are selected to result in a stable compound of Ln'.sub.x O.sub.y.

Ternary silicon-rare earth nitrides and process for their preparation

Novel gel-forming compositions are used in a process for molding ceramic compositions. Gel-forming compositions, such as agar, are improved with a gel-enhancing agent, e.g. polyethyleneimine. The novel gel-forming compositions improved the ceramic molding process and/or the ceramic products formed therefrom.

A process for shaping parts from ceramic powder that comprises the steps of (1) forming a concentrated mixture in excess of 40% ceramic solids by volume, the mixture comprising ceramic powder, a gel forming material chosen from the class of polysaccharides known as 'agaroids', and a gel forming material solvent and being formed in a blender that provides a shearing action and is heated to raise the temperature of the mixture to about 70.degree. C. to 100.degree. C.; and (2) molding the mixture at a temperature sufficient to produce a self-supporting structure comprising the powder and gel. The parts exhibit excellent green strength and are rapidly fired without cracking, distortion or shrinkage problems.

Aqueous process for injection molding ceramic powders at high solids

A ceramic element of a zirconia oxygen sensor is shaped from a powder mixture. The mixture, comprising a ceramic powder having an average particle size less than or equal to 1 micrometer, a gel-forming material and a gel forming material solvent, is molded at a temperature and pressure sufficient to produce the ceramic element having a density of at least 5.5 g/cm.sup.3.

Injection molding of zirconia oxygen sensor thimbles by an aqueous

Zirconia toughened alumina (ZTA) is produced from precursor salts. The precursor salts are coprecipitated from solution to yield a gel in a liquid phase. The gel in excess of the critical temperature and pressure is dried at a temperature and pressure in excess of the critical temperature and pressure of the liquid phase to thereby convert the liquid phase to a gas. The solid particles, when separated from the gas, form a fine particulate ZTA which, upon consolidation yields near theoretical density toughened ceramics.

Process for making zirconia-alumina

A process for shaping parts from metallic and/or ceramic powders is disclosed. The process comprises the steps of forming a mixture comprising metal and/or ceramic powders, a gel-forming material having a gel strength, measured at a temperature between 0.degree. C. and about 22.degree. C. and a gel consisting essentially of about 4 wt. % of the gel-forming material and water, of at least about 100 g/cm.sup.2, and a gel-forming material solvent, and molding the mixture at a temperature sufficient to produce a self-supporting article comprising the powder and a gel. The preferred gel-forming material is an agaroid and the preferred molding process is injection molding.

Process for injection molding ceramic composition employing an agaroid

Inorganic metal oxides having high surface area and pore volume are prepared by spray drying. The admixture which is spray dried to yield the metal oxides is produced from reactants comprising at least one hydrolyzable metal compound, a sufficient amount of water to at least partially hydrolyze the metal compound and an organic solvent. The admixture is supplied as a plurality of droplets to a reaction zone operated under conditions of temperature and pressure below the critical temperature and pressure of the reactants but sufficient to produce a product comprising metal oxide powders and a gas comprising organic solvent vapors. The powders are separated from the gas in a known fashion and collected. Spray drying of non-aqueous systems unexpectedly produces metal oxides having properties generally intermediate conventionally produced oxides and aerogels.

Spray-dried inorganic oxides from non-aqueous gels or solutions

A process using hydrogen dissolving metals, alloys and intermetallic compounds to drive otherwise thermodynamically unfavorable dehydrogenation reactions is disclosed. The process comprises the steps of selecting an organic reactant comprising carbon and hydrogen, and exposing the organic reactant to a material at a temperature and pressure sufficient to remove at least one hydrogen from one said organic reactant and to form a material hydride, the material being selected from the group of metals, alloys and intermetallic compounds having a negative standard free energy of formation for a hydrided product MH.sub.y, where M is the material, H is hydrogen and y is a non-zero number between 0 and about 4 and represents the total hydrogen to material atom ratio wherein the standard free energy change for the reaction of the organic rectant in the present of the material to remove at least one hydrogen atom therefrom and from the material hydride is negative.

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Rockaway, NJ, United States of America

Anthony J Fanelli