Air Products and Chemicals, Inc.

Chemetall Gmbh

Dart Industries Inc.

Analog Technology Corporation

Other

Uti-spectrotherm Corporation

Composite Tool Company, Inc.

Robert A Holzl

Robert E Benander

Paul N Dyer

Vincent L Magnotta

James L Lawrence, Jr

Frederick P Pickett

Benjamin H Tilley

Robert J Shinavski

Howard P Withers, Jr

Richard E Tressler

Robert D Davis

Robert L Shinavski

Yvonne R DeKay

A family of extremely fine-grained alloys are used to make coatings or free-standing bodies having desirable properties for use as a heat-resistant and wear-resistant material. In an illustrative embodiment, the alloys are comprised of a multiplicity of alternate, microcrystalline or nanocrystalline films of tungsten metal and tungsten compound. The tungsten compound film may be comprised of a tungsten carbide or a tungsten boride. The tungsten films are the primary films. Their desirable characteristics, in addition to their very fine crystalline habit, per se, are the high strength, high hardness, high resilience, and high fracture energy which these fine crystallites foster. They may be manufactured by a chemical vapor deposition process in which reactive gas flows are rapidly switched to produce alternate films with abrupt hetero-junctions and thereby to produce the useful micro-crystalline habit. The unique synthesis method allows effective control of critical flaw size. The structure is such that the primary films may be made sufficiently thick so as to assure some desirable ductile behavior, but sufficiently thin so as to have high yield strength by dint of their microcrystalline size, and as to limit the size of any flaws. The secondary films are made of enough thickness to prevent the epitaxial growth from one primary film to the next-deposited primary film and thin enough so that they can not contain a flaw of critical size. In addition, the exterior surface of any body made by this method may have a sufficiently smooth surface that the strength of the body is determined by the bulk properties of the material and not by surface flaws.

High strength alloys and methods for making same

A coated carbon body having improved resistance to high temperature oxidation and a method for producing the coated carbon body are described. The coated carbon body comprises a carbon body, an intermediate glass forming coating within said converted layer, and an outer refractory coating on the intermediate coating. The body has a converted porous layer formed by etching and reacting the body with gaseous boron oxide and the resulting converted layer contains interconnecting interstices and boron carbide formed by the reaction of the boron oxide and the carbon body. The method comprises contacting a carbon body with boron oxide at an elevated temperature sufficient to cause the reaction between the carbon body and boron oxide to form a converted porous layer which contains interconnecting interstices in the body and boron carbide and then applying the intermediate glass forming coating over the converted layer and an outer refractory coating over the intermediate coating.

Oxidation resistant carbon and method for making same

A coated carbon body having improved resistance to high temperature oxidation and a method for producing the coated carbon body are described. The coated carbon body comprises a carbon body, an intermediate glass forming coating and an outer refractory coating on the intermediate coating. The body has a converted porous layer formed by etching and reacting the body with boron oxide and the resulting converted layer contains interconnecting interstices and boron carbide formed by the reaction of the boron oxide and the carbon body. The method comprises contacting a carbon body with boron oxide at an elevated temperature sufficient to cause the reaction between the carbon body and boron oxide to form a converted porous layer which contains interconnecting interstices in the body and boron carbide and then applying the glass forming coating over the converted layer. Preferably an outer refractory coating is applied over the glass forming coating. The glass forming coating comprises compounds selected from the group consisting of silicon nitride, silicon oxynitride and mixtures thereof. Additionally, both the refractory outer coating and the glass forming coating can contain compounds selected from the group consisting of silicon nitride, silicon oxynitride, and mixtures thereof.

A structural article for high temperature applications comprises a body formed of at least partially consolidated, particulate silicon nitride, a conformal outer coating of silicon nitride or silicon carbide on the body, and a conformal intermediate layer of a silicon, oxygen and nitrogen-containing compound, i.e. silicon oxynitride, chemically bonded to both the body and the outer coating. The method for making such an article comprises providing a body formed of at least partially consolidated, particulate silicon nitride, oxidizing the surface of the body, removing silicon dioxide from the oxidized surface of the body; and chemically vapor depositing a conformal outer coating of silicon nitride or silicon carbide. The conformal outer coating provides a protective envelope around and assists in high temperature isostatic pressing of the body and hence permits one to use the structural article in isostatic pressing processes.

Structral articles

A method for making a lightweight structure having a high stiffness to weight ratio comprising providing a substrate defining at least a pair of outer surfaces spaced from each other, boring at least one hole through the structure to provide at least one void passage extending through the substrate between the outer surfaces, coating the outer surfaces of the substrate and the surfaces of the passage with a chemical vapor deposited material to a thickness of about one millimeter, plugging the void passage with a plug of a substrate material, and further coating the coated outer surfaces of the substrate and the ends of the plugs with a chemical vapor deposited material to form a continuous monolithic structure thereon.

Composite stiff lightweight structure and method for making same

A composite structure having a high stiffness to weight ratio includes a substrate, e.g. graphite, defining at least a pair of outer surfaces which are spaced from each other and having a volume or void passages extending through the substrate between the outer surfaces. At least one stiffening element extends between the outer surfaces within this volume. The stiffening element defines a volume and has at least one wall intersecting each of the outer surfaces. The stiffening element and the outer surfaces are made up of a chemically vapor deposited material having the desired high stiffness to weight ratio and being formed as a monolithic structure having a thickness of at least about 1 millimeter. These structures have such diverse uses as aircraft parts and skis.

The invention relates to an method of producing a titanium aluminide coating on a substrate by producing a flow of hydrogen and gaseous aluminum monochloride over a titanium surface to react to form a gaseous flow of titanium trichloride and aluminum monochloride and contacting the substrate with the flow of titanium trichloride and aluminum monochloride at a temperature of 800.degree. to 1200.degree. C., said substrate being a temperature below the temperature of the gases.

Deposition of titanium aluminides

A method of forming a coated article is described. The article is composed of a carbon body having a thermochemically deposited coating which renders the body resistant to oxidation at high temperatures. A volatile gaseous halide of silicon is partially reduced to form a lower halide in a first reaction zone having a first pressure and separated from the body. The lower halide is flowed into a second reaction zone maintained at a pressure lower than the pressure in the first reaction zone. A gaseous alloying agent is introduced into the second reaction zone. The agent includes one or more elements selected from the group consisting of carbon, oxygen, aluminum, and nitrogen. As a consequence, a liquid phase intermediate compound is deposited on the substrate body which is thereafter thermochemically reacted to produce a coating of the silicon alloy. The coating has a non-columnar grain distribution with substantially equiaxial grains of an average diameter of less than one micron and forms a correspondingly fine crack mosaic upon stressing due to differences in thermal coefficients of expansion between the coating and the body. The lower halide and the alloying agent are controlled so as to produce a coating wherein the amount of silicon is substantially in excess of stoichiometry.

Method for making self-protecting carbon bodies

A coated article and method of forming the same. The article is composed of a carbon body having a thermochemically deposited coating which renders the body resistant to oxidation at high temperatures. The coating is formed of a silicon alloy having a non-columnar grain distribution with substantially equiaxial grains of an average diameter of less than one micron. The amount of silicon in the coating is in excess of the alloy stoichiometry, producing infusion of silicon, with such at or above its melting temperature, into the cracked mosaic of the coating, to form an oxidative resistant glass filler.

Self protecting carbon bodies and method for making same

A hard fine-grained internally stressed material of tungsten and carbon or tungsten, carbon and oxygen is described which is produced by thermochemical deposition. The material consists primarily of a two phase mixture of pure tungsten and an A15 structure, is free of columnar grain distribution, and has a hardness of greater than 1,200 VHN. The average grain size is less than 0.1 micron.

Tungsten alloys containing A15 structure and method for making same

A method of depositing a hard, fine grained metal or semi-metal alloy is described wherein a volatile halide of the metal or semi-metal is partially reduced and then deposited as a liquid phase intermediate compound onto a substrate in the presence of an alloying gas. The liquid phase deposited on the substrate is then thermochemically reacted to produce the hard, fine grained alloy. Also described are products which may be produced by the above method.

Deposition method and products

A process for producing mass filters for use in mass spectrometers. Several electrodes having precisely shaped surfaces must be held in precisely determined positions with respect to each other. Insulators are placed into position on the surface of a mandrel and a layer of metal is deposited over the mandrel and insulators to form a composite unitary structure, including the electrodes. The deposited metal overlying the insulators is then removed, electrically isolating the electrodes.

Mass spectrometer filter

A method for producing a hard deposit on a substrate is described wherein a volatile halide of tungsten or molybdenum is reacted with a gas or gases containing hydrogen, oxygen and carbon to effect the deposition on a substrate of a compound of the metal in a liquid phase. The liquid phase deposited on the substrate is then reacted to remove oxygen and halogen and produce a hard deposit containing the metal and carbon. Also described are products which may be produced by the above method.

Growing community of inventors

La Canada, CA, United States of America

Robert A Holzl