Patents Represented by Attorney Andrew Alexander
  • Patent number: 4737246
    Abstract: An improved process is provided for the production of aluminum reflective material having a higher total reflectance value. The process comprises controlling the anodizing conditions of a bright rolled aluminum alloy by immersing the alloy in a DC anodizing bath containing at least 26 wt. % sulfuric acid and the anodizing sheet at a current density of at least 1.94 amperes per square decimeter (18 amperes per square foot) at a temperature of from 15.56.degree. to 27.78.degree. C. (60.degree. to 82.degree. F.) for a time period of from about 0.5 to 10 minutes to provide a coating thickness of from about 0.06 to 0.22 mils. The process permits a highly reflective surface to be formed without subjecting the aluminum to a preliminary brightening process prior to anodizing.
    Type: Grant
    Filed: December 6, 1985
    Date of Patent: April 12, 1988
    Assignee: Aluminum Company of America
    Inventors: John H. Powers, Hang T. Dang
  • Patent number: 4735922
    Abstract: A porous refractory hard metal composition is disclosed which is formed by removing the metal compound from a substantially interwoven matrix composition comprising one or more refractory hard metals and a metal compound. The interwoven matrix composition, in a preferred embodiment, may comprise Al.sub.2 O.sub.3 and TiB.sub.2, ZrB.sub.2, or a mixture of the two refractory hard metals.
    Type: Grant
    Filed: October 21, 1985
    Date of Patent: April 5, 1988
    Assignee: Aluminum Company of America
    Inventor: Siba P. Ray
  • Patent number: 4735654
    Abstract: An improved process is disclosed for carbothermically producing an alkaline earth metal aluminide from an aluminum-bearing material which, in one aspect comprises forming a mixture of a carbonaceous reducing agent and a slag comprising the aluminum-bearing material, the alkaline earth metal compound; forming, at a first temperature, an alloy containing impurities in the slag; removing the alloy containing the impurities from the slag; and then heating the slag to a higher temperature to form the alkaline earth metal aluminide. The alkaline earth metal compound used in the process may comprise calcium carbide. Alternatively, both the alkaline earth metal compound and the aluminum-bearing material may be obtained using a calcium aluminate slag such as a byproduct from the steel industry. The calcium aluminate slag is purified in a preliminary step to remove silicon by alloying it with iron and then removing a ferrosilicon alloy formed in this step.
    Type: Grant
    Filed: December 24, 1986
    Date of Patent: April 5, 1988
    Assignee: Aluminum Company of America
    Inventors: C. Norman Cochran, Melvin H. Brown
  • Patent number: 4735773
    Abstract: A system is disclosed for efficiently mixing streams of molten metal to form a molten metal alloy while inhibiting oxidation and introduction of impurities such as hydrogen gas into the molten metal which comprises passing a first molten metal stream at a minimum velocity of at least 18 cm/sec into a mixing zone and feeding a second molten metal stream at a lower velocity into the mixing zone through a concentric feed tube around which the first molten metal stream is flowing. The first molten metal stream is maintained in turbulent flow conditions with a Reynolds number of greater than 2100. In a preferred embodiment, the minimum velocity of the first stream is raised before reaching the mixing zone by introducing a non-oxidizing gas into the stream.
    Type: Grant
    Filed: December 8, 1986
    Date of Patent: April 5, 1988
    Assignee: Aluminum Company of America
    Inventor: Charles E. Eckert
  • Patent number: 4729058
    Abstract: The invention discloses a self-limiting ceramic capacitor characterized by high capacitance and transient voltage protective properties comprising a plurality of thin layers of a zinc oxide-based ceramic material having non-linear resistance characteristics with each layer having a conductive coating on at least one surface thereof and the coated ceramic layers sintered together to form a laminated stack. A conductive coating comprising a first electrode of the capacitor is formed on a first edge of the laminated stack of layers and is in electrical communication with a portion of the conductive coating on some of the layers extending to that edge of the layer.
    Type: Grant
    Filed: December 11, 1986
    Date of Patent: March 1, 1988
    Assignee: Aluminum Company of America
    Inventors: Tapan K. Gupta, William D. Straub
  • Patent number: 4724134
    Abstract: The invention comprises high purity substantially spherical metal oxide particles having one or more predominant particle sizes formed from one or more metal alkoxides. In one embodiment there is disclosed multimodal particle size distributions of such substantially spherical metal hydroxide particles while a second embodiment describes the formation of such particles using more than one metal alkoxide to form either a mixed metal hydroxide particle or a layered particle comprising a core of a first metal hydroxide and at least one layer of an additional metal hydroxide.
    Type: Grant
    Filed: October 21, 1985
    Date of Patent: February 9, 1988
    Assignee: Aluminum Company of America
    Inventor: Ajay Sood
  • Patent number: 4724054
    Abstract: An improved process is disclosed for carbothermically producing an alkaline earth metal aluminide from an aluminum-bearing material which, in one aspect comprises forming a mixture of a carbonaceous reducing agent and a slag comprising the aluminum-bearing material, the alkaline earth metal compound, forming, at a first temperature, an alloy containing impurities in the slag; removing the alloy containing the impurities from the slag; and then heating the slag to a higher temperature to form the alkaline earth metal aluminide. The alkaline earth metal compound used in the process may comprise calcium carbide. Alternatively, both the alkaline earth metal compound and the aluminum-bearing material may be obtained using a calcium aluminate slag such as a byproduct from the steel industry. The calcium aluminate slag is purified in a preliminary step to remove silicon by alloying it with iron and then removing a ferrosilicon alloy formed in this step.
    Type: Grant
    Filed: December 24, 1986
    Date of Patent: February 9, 1988
    Assignee: Aluminum Company of America
    Inventors: Melvin H. Brown, C. Norman Cochran
  • Patent number: 4717692
    Abstract: A composite is disclosed which comprises one or more interwoven matrix compositions, each containing a refractory hard metal; and from 0 to 80 wt. % of at least one previously formed refractory hard metal. In one embodiment, the composite may comprise two interwoven matrix compositions which were formed by mixing the reactants together prior to forming the interwoven matrix compositions whereby the exothermic heat of react may be controlled by selection of proper ratios of reactants. In another embodiments, previously formed refractory hard metals or previously formed interwoven matrix compositions may be used in the formation of the composite to control the exothermic heat liberated during formation of the interwoven matrix composition or for other purposes such as densification of the composite.
    Type: Grant
    Filed: October 21, 1985
    Date of Patent: January 5, 1988
    Assignee: Aluminum Company of America
    Inventor: Siba P. Ray
  • Patent number: 4717483
    Abstract: An improved process is disclosed for the simultaneous removal of ammonia, sulfides and organic impurities from an impure aqueous stream from a tanning process which comprises contacting the impure stream with an adsorbent comprising a mixture of alumina and a Y zeolite.
    Type: Grant
    Filed: June 23, 1986
    Date of Patent: January 5, 1988
    Assignee: Aluminum Company of America
    Inventors: John F. Bush, Hubert L. Fleming
  • Patent number: 4714494
    Abstract: A system for purification of molten metal to remove impurities such hydrogen gas and alkali elements therefrom is disclosed which comprises passing the molten metal through an enclosed passageway at a velocity of at least about 0.1 cm/sec and introducing a sparging gas into the passageway whereby the velocity of the molten metal will shear off bubbles of the sparging gas as they are formed resulting in smaller bubbles with larger gas/molten metal interface area to achieve maximum contact between the sparging gas and the molten metal to enhance removal of impurities from the molten metal.
    Type: Grant
    Filed: December 8, 1986
    Date of Patent: December 22, 1987
    Assignee: Aluminum Company of America
    Inventor: Charles E. Eckert
  • Patent number: 4711115
    Abstract: A flat, smooth material, e.g., metal sheet, suitable for use as a disc substrate for applying a recording media thereto for data storage devices, and a method of making same, are disclosed. The flat and smooth substrate is formed by applying sufficient pressure to opposite surfaces of the material to achieve the desired flatness and smoothness prior to finishing. Subsequent finishing may be used to remove any zone of roughness which may be present in the surfaces of the disc resulting from the pressing step. In one embodiment, the pressure step may be applied before finishing the disc perimeters.
    Type: Grant
    Filed: December 30, 1985
    Date of Patent: December 8, 1987
    Assignee: Aluminum Company of America
    Inventors: Israil M. Sukonnik, John S. Judge, Colin H. Kilgore
  • Patent number: 4711762
    Abstract: An improved aluminum base alloy product is disclosed, the product comprising 0 to 3.0 wt. % Cu, 0 to 1.5 wt. % Mn, 0.1 to 4.0 wt. % Mg, 0.8 to 8.5 wt. % Zn, at least 0.005 wt. % Sr, max. 1.0 wt. % Si, max. 0.8 wt. % Fe and max. 0.45 wt. % Cr, 0 to 0.2 wt. % Zr, the remainder aluminum and incidental elements and impurities.
    Type: Grant
    Filed: September 22, 1982
    Date of Patent: December 8, 1987
    Assignee: Aluminum Company of America
    Inventors: William D. Vernam, Bernard W. Lifka
  • Patent number: 4698319
    Abstract: A densified composite is disclosed which comprises one or more substantially interwoven matrix compositions, which have been densified either during formation of the interwoven matrix composition to provide a composite having a low porosity and a density of at least 75% of the theoretical density. The interwoven matrix composition may be densified during formation either by the addition to the reactants of a densification agent or by maintaining sufficient pressure on the reactants during the formation of the interwoven matrix. The densification of the interwoven matrix may be carried out after formation of the interwoven matrix composition either by heating the composition to a sufficient temperature for a sufficient time period to achieve the desired densification or by immersing the interwoven matrix composition in a molten metal or a molten metal salt to impregnate the interwoven matrix composition to achieve the desired densification.
    Type: Grant
    Filed: October 21, 1985
    Date of Patent: October 6, 1987
    Assignee: Aluminum Company of America
    Inventor: Siba P. Ray
  • Patent number: 4693747
    Abstract: Disclosed is a metal alloy product having increased resistance to fatigue crack growth and having coarse grains distributed in a fine grain structure, the coarse grains having a different alloy composition from the fine grain structure.
    Type: Grant
    Filed: November 18, 1985
    Date of Patent: September 15, 1987
    Assignee: Aluminum Company of America
    Inventors: Philip E. Bretz, Jocelyn I. Petit, Ralph R. Sawtell, Asuri K. Vasudevan
  • Patent number: 4687439
    Abstract: An improved exhaust port plug is provided for use in a baking furnace for the baking of anodes for use in an electrolytic reduction cell. The improved exhaust port plug comprises a cylindrical metal shell having a diameter approximating the diameter of the port, a cover member on the shell having a dimension exceeding the diameter of the port, a gasket means on the underside of the cover member surrounding the shell and adapted to sealingly engage an external portion of the furnace, a mat of packed ceramic fibers within the shell, and retaining means to retain the mat of ceramic fibers within the metal shell.
    Type: Grant
    Filed: February 28, 1986
    Date of Patent: August 18, 1987
    Assignee: Aluminum Company of America & Delta Refractories, Inc.
    Inventors: Flavio Olivarez, Jr., Richard J. Walla
  • Patent number: 4685505
    Abstract: An improvement in roll casting apparatus is disclosed which comprises side edge dam means for delivering a flow of gas toward the side edges of metal as it passes, from a source of molten metal, through a pair of opposing roll casting means to thereby contain the side flow of such metal during the roll casting operation. In a preferred embodiment, the gas is directed toward the cast metal through porous side edge dam means attached to a plenum which is inserted into the nip of the roll casting means.
    Type: Grant
    Filed: January 6, 1986
    Date of Patent: August 11, 1987
    Assignee: Aluminum Company of America
    Inventors: William G. Truckner, Charles L. Jordan, William R. Sharkins
  • Patent number: 4686198
    Abstract: A process is described for regeneration of an adsorbent having ammonia adsorbed thereon and comprising a mixture of an alumina and a Y zeolite. The adsorbent may be regenerated to substantially its original capacity for adsorbing ammonia by a two step process which comprises first treating the adsorbent with a saturated solution of an alkali metal carbonate such as sodium carbonate to remove a substantial portion of the ammonia sorbed on the adsorbent mixture and then treating the adsorbent in a second step with a saturated alkali metal bicarbonate solution such as sodium bicarbonate to restore the ammonia adsorption capacity of the adsorbent mixture to substantially its original capacity.
    Type: Grant
    Filed: June 23, 1986
    Date of Patent: August 11, 1987
    Assignee: Aluminum Company of America
    Inventors: J. Finley Bush, Donald R. Mydock
  • Patent number: 4678760
    Abstract: The invention discloses an improvement in a process wherein a first reactant comprising one or more metals or metal compounds exothermically reacts with a second reactant comprising at least one or more metals or metal compounds in the presence of a third reactant to form an interwoven matrix of a conductive material and an insulating material. The improvement comprises locally applying, to a selected region of a shaped body formed from a mixture of the reactants, sufficient energy to initiate an exothermic reaction which then propagates throughout the remainder of the body to form the interwoven matrix.
    Type: Grant
    Filed: October 21, 1985
    Date of Patent: July 7, 1987
    Assignee: Aluminum Company of America
    Inventor: Siba P. Ray
  • Patent number: 4678657
    Abstract: The invention comprises a process for the production of high purity substantially spherical metal oxide particles using seed nuclei without introducing impurities into the desired product which comprises forming a metal alkoxide vapor; reacting the vapor with a non-reactive gas containing sufficient water vapor to hydrolyze a portion of the metal alkoxide vapor to form solid seed nuclei of metal hydroxide; cooling the remaining metal alkoxide vapor containing the metal hydroxide seed nuclei sufficiently to form an aerosol comprising finely divided metal alkoxide liquid condensed on the solid metal hydroxide seed nuclei; hydrolyzing the metal alkoxide aerosol by contact with water vapor to hydrolyze the metal alkoxide liquid to form substantially spherical metal hydroxide particles; and calcining the substantially spherical metal hydroxide particles to form the corresponding metal oxide.
    Type: Grant
    Filed: June 10, 1985
    Date of Patent: July 7, 1987
    Assignee: Aluminum Company of America
    Inventors: Ajay Sood, Robert A. Marra
  • Patent number: 4678477
    Abstract: A system is disclosed for the purification of a caustic solution to remove impurities therefrom comprises: bringing the caustic solution into contact under pressure with the outside of a plurality of porous hollow fibers each having at least one open end and coated with a semipermeable membrane and collecting purified solution from the open ends of the hollow fibers. In a preferred embodiment, the filtering medium comprises porous hollow polysulfone fibers coated with a semipermeable sulfonated polysulfone membrane.
    Type: Grant
    Filed: January 6, 1986
    Date of Patent: July 7, 1987
    Assignee: Aluminum Company of America
    Inventors: Paul J. The, Chanakya Misra