Air Products and Chemicals, Inc.

David L Mitchell, Jr

Robert B Swan

Diwakar Garg

Zbigniew Zurecki

Edward A Hayduk, Jr

John G North

Kerry R Berger

Edward F Kiczek

Kevin S McAfee

Earl W Moore

Brian B Bonner

Donald J Bowe

Paul Anthony Mattiola

James Garfield Marsden

Paul T Kilhefner, Iii

An improved process for humidifying a gas stream with a precise amount of moisture used in a variety of heat treating processes including annealing, brazing, and sintering of ferrous and non-ferrous metals and alloys, reflow soldering of electronic components, glass-to-metal sealing, chemical processes, chemical vapor deposition of metal oxides, laser processing, fuel cells, etc. The gaseous stream is humidified by introducing a controlled amount of water through a precision metering device and a known and precise flow rate of a gas stream into a gas-liquid contactor, and shearing and vaporizing the water stream in the gas-liquid contactor with the gas stream.

Process for humidifying a gas stream

The present invention discloses novel nitrogen-hydrogen based atmospheres for sintering steel components in continuous furnaces with consistent quality and properties while prolonging the life of the wire mesh belts, reducing maintenance costs, and improving furnace productivity. Specifically, it discloses the use of a controlled amount of an oxidizing agent such as moisture, carbon dioxide, nitrous oxide, or mixtures thereof along with nitrogen-hydrogen atmospheres. The amount of an oxidizing agent added to the nitrogen-hydrogen atmospheres to pre-condition belt material prior to its use for sintering and to sinter steel components is controlled in such a way that atmospheres become oxidizing to the belt material but reducing to steel components being sintered, specifically in the high heating and cooling zones of continuous furnaces.

Atmospheres for extending life of wire mesh belts used in sintering

Graphite carbon surfaces are protected from elevated temperature oxidation and mechanical wear by electric arc thermal spray coating exposed surfaces with a titanium nitride or multi-element (e.g., aluminum-silicon-titanium) coating.

Graphite/carbon articles for elevated temperature service and method of

An improved method for producing substantially moisture- and oxygen-free, nitrogen-hydrogen atmospheres suitable for annealing, hardening, brazing, and sintering ferrous and non-ferrous metals and alloys is disclosed. According to the disclosed method, suitable nitrogen-hydrogen atmosphere is produced by 1) generating a nitrogen stream containing about 0.1 to 5% residual oxygen by a known non-cryogenic air separation technique, 2) mixing it with a pre-determined but more than stoichiometric amount of hydrogen required to convert residual oxygen to moisture, 3) converting residual oxygen to moisture by reaction with hydrogen in a catalytic reactor, 4) cooling the reactor effluent stream, and 5) removing moisture from it in a regenerative sorbent dryer.

Method of producing nitrogen-hydrogen atmospheres for metals processing

Graphite and/or carbon surfaces are coated with a titanium nitride coating by exposing the substrate to electric arc thermal spray process wherein titanium wire as the source of titanium and nitrogen is used as the propelling (atomizing) gas.

Method of forming titanium nitride coatings on carbon/graphite

Method and apparatus for quick freezing particles with surface moisture by immersion in liquid cryogen to produce a frozen crust or layer on the particles followed by agitation in content with the vaporized cryogen to complete freezing and prevent clumping of the particles.

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Coopersburg, PA, United States of America

David L Mitchell, Jr