Patents by Inventor Siba P. Ray
Siba P. Ray has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 6309994Abstract: A method of forming fiber reinforced aluminum phosphate bonded material having improved strength at elevated temperatures. The method comprises the steps of: (a) preparing a slurry by blending alumina and alumina phosphate solution, the slurry being substantially free of silica; (b) providing a fiber substrate; (c) infiltrating the solution into the fiber substrate; and (d) curing the infiltrated substrate to form a fiber reinforced aluminum phosphate bonded composite material. In a preferred embodiment of the present invention, the fiber substrate is made from SiC fibers.Type: GrantFiled: August 14, 1989Date of Patent: October 30, 2001Assignee: Aluminum Company of AmericaInventors: Robert A. Marra, Donald J. Bray, G. Edward Graddy, Jr., Siba P. Ray
-
Patent number: 6217739Abstract: A method of producing commercial purity aluminum in an electrolytic reduction cell comprising inert anodes is disclosed. The method produces aluminum having acceptable levels of Fe, Cu and Ni impurities. The inert anodes used in the process preferably comprise a cermet material comprising ceramic oxide phase portions and metal phase portions.Type: GrantFiled: November 1, 1999Date of Patent: April 17, 2001Assignee: Alcoa Inc.Inventors: Siba P. Ray, Xinghua Liu, Douglas A. Weirauch, Jr.
-
Patent number: 6187168Abstract: An electrolytic cell and electrolytic process for producing a metal by reduction of a metal oxide dissolved in a molten salt bath containing at least one chloride and at least one fluoride. A solid conductor of oxide ions is interposed between the anode and the cathode. The solid conductor preferably comprises zirconia, stabilized in cubic form by addition of a divalent or trivalent metal oxide such as yttria.Type: GrantFiled: October 6, 1998Date of Patent: February 13, 2001Assignee: Aluminum Company of AmericaInventors: Alfred F. LaCamera, Siba P. Ray
-
Inert anode containing base metal and noble metal useful for the electrolytic production of aluminum
Patent number: 6162334Abstract: An inert anode for production of metals such as aluminum is disclosed. The inert anode comprises a base metal selected from Cu and Ag, and at least one noble metal selected from Ag, Pd, Pt, Au, Rh, Ru, Ir and Os. The inert anode may optionally be formed of sintered particles having interior portions containing more base metal than noble metal and exterior portions containing more noble metal than base metal. In a preferred embodiment, the base metal comprises Cu, and the noble metal comprises Ag, Pd or a combination thereof.Type: GrantFiled: October 27, 1999Date of Patent: December 19, 2000Assignee: Alcoa Inc.Inventors: Siba P. Ray, Xinghua Liu -
Patent number: 6126799Abstract: A cermet composite material is made by treating at an elevated temperature a mixture comprising a compound of iron and a compound of at least one other metal, together with an alloy or mixture of copper and a noble metal. The alloy or mixture preferably comprises particles having an interior portion containing more copper than noble metal and an exterior portion containing more noble metal than copper. The noble metal is preferably silver. The cermet composite material preferably includes alloy phase portions and a ceramic phase portion. At least part of the ceramic phase portion preferably has a spinel structure.Type: GrantFiled: February 1, 1999Date of Patent: October 3, 2000Assignee: Alcoa Inc.Inventors: Siba P. Ray, Robert W. Woods, Robert K. Dawless, Robert B. Hosler
-
Patent number: 6036792Abstract: A novel product composed of a ceramic phase particle dispersoid in metal, including uniformly distributed, finely sized carbide phase particles formed in situ in a molten metal and a novel method for producing such a ceramic phase particle dispersoid in metal are disclosed. A salt-based liquid state reaction involving a liquid metal/alloy containing a liquid Ti, B, Si, Sc, Hf, Nb, Ta, Zr, Mo, Al (when the molten metal matrix is not aluminum), or V and a halide salt containing carbon particles forms a uniform distribution of finely sized ceramic phase particles formed and dispersed in-situ in the metal matrix. The ceramic dispersoid in metal product of the present invention includes at least about 50 volume percent of a matrix metal of aluminum; and up to about 50 volume percent of a uniform distribution of finely sized ceramic phase particles formed and dispersed in-situ in the aluminum metal matrix, wherein the finely sized ceramic phase particles have an average particle diameter of less than about 2.Type: GrantFiled: April 1, 1998Date of Patent: March 14, 2000Assignee: Aluminum Company of AmericaInventors: Men Glenn Chu, Siba P. Ray
-
Patent number: 6030518Abstract: Aluminum is produced by electrolytic reduction of alumina in a cell having a cathode, an inert anode and a molten salt bath containing metal fluorides and alumina. The inert anode preferably contains copper, silver and oxides of iron and nickel. Reducing the molten salt bath temperature to about 900-950.degree. C. lowers corrosion on the inert anode constituents.Type: GrantFiled: September 10, 1997Date of Patent: February 29, 2000Assignee: Aluminum Company of AmericaInventors: Robert K. Dawless, Siba P. Ray, Robert B. Hosler, Robert L. Kozarek, Alfred F. LaCamera
-
Patent number: 5989310Abstract: A novel method for producing a ceramic phase particle dispersoid in metal and a novel product composed thereof. The method includes (a) providing a molten composition consisting essentially of molten aluminum alloy containing molten metal selected from the group consisting of Zr, V and combinations thereof, (b) providing a chloride salt containing fine carbon particles; and (c) reacting the chloride salt containing fine carbon particles in the molten aluminum metal with the molten metal to form a uniform distribution of finely sized carbide particles formed and dispersed in-situ in an aluminum alloy matrix.Type: GrantFiled: November 25, 1997Date of Patent: November 23, 1999Assignee: Aluminum Company of AmericaInventors: Men Glenn Chu, Siba P. Ray
-
Patent number: 5938914Abstract: An electrolytic cell for reduction of a metal oxide to a metal and oxygen has an inert anode and an upwardly angled roof covering the inert mode. The angled roof diverts oxygen bubbles into an upcomer channel, thereby agitating a molten salt bath in the upcomer channel and improving dissolution of a metal oxide in the molten salt bath. The molten salt bath has a lower velocity adjacent the inert anode in order to minimize corrosion by substances in the bath. A particularly preferred cell produces aluminum by electrolysis of alumina in a molten salt bath containing aluminum fluoride and sodium fluoride.Type: GrantFiled: September 19, 1997Date of Patent: August 17, 1999Assignee: Aluminum Company of AmericaInventors: Robert K. Dawless, Alfred F. LaCamera, R. Lee Troup, Siba P. Ray, Robert B. Hosler
-
Patent number: 5865980Abstract: An inert electrode material is made by reacting at an elevated temperature a mixture preferably comprising iron oxide, at least one other metal oxide, copper and silver. The reaction produces a material having ceramic phase portions and alloy phase portions, wherein the alloy phase portions have copper-rich interior portions and silver-rich exterior portions. Inert anodes made with a reaction mixture containing copper and silver have lower wear rates than inert anodes made with copper and no silver.Type: GrantFiled: June 26, 1997Date of Patent: February 2, 1999Assignee: Aluminum Company of AmericaInventors: Siba P. Ray, Robert W. Woods, Robert K. Dawless, Robert B. Hosler
-
Patent number: 5794112Abstract: A process for making an inert electrode composite wherein a metal oxide and a metal are reacted in a gaseous atmosphere at an elevated temperature of at least about 750.degree. C. The metal oxide is at least one of the nickel, iron, tin, zinc and zirconium oxides and the metal is copper, silver, a mixture of copper and silver or a copper-silver alloy. The gaseous atmosphere has an oxygen content that is controlled at about 5-3000 ppm in order to obtain a desired composition in the resulting composite.Type: GrantFiled: June 26, 1997Date of Patent: August 11, 1998Assignee: Aluminum Company of AmericaInventors: Siba P. Ray, Robert W. Woods
-
Patent number: 5735976Abstract: A novel method for producing a ceramic phase particle dispersoid in metal and a novel product composed thereof are disclosed, including finely sized carbide phase particles formed in situ in a molten metal by salt-based liquid state reaction with Ti, B, Si, Sc, Hf, Nb, Ta, Zr, Mo, Al (when the molten metal matrix is not aluminum), or V and a halide salt containing carbon particles to form a uniform distribution of finely sized ceramic phase particles formed and dispersed in-situ in the metal matrix. The step of reacting includes vigorously stirring to form a reaction mixture at an elevated temperature for a residence time less than one hour to form a uniform distribution of particles sized less than 2.5 microns uniformly dispersed in-situ in the metal matrix.Type: GrantFiled: January 31, 1996Date of Patent: April 7, 1998Assignee: Aluminum Company of AmericaInventors: Men Glenn Chu, Siba P. Ray
-
Patent number: 5492604Abstract: A method for producing a metal in an electrolysis cell comprising an anode, a carbon cathode, and a chamber containing a metal oxide dissolved in a molten salt bath, said method comprising: coating an outer surface portion of the cathode with a coating composition consisting of a refractory metal, a paint comprising an organic polymeric binder, and aluminum powder, and optionally an organic solvent and an oil; and optionally a boron source; curing the coating composition by heating it to an elevated temperature, producing an aluminum-wettable coating on the cathode outer surface portion; and electrolyzing the metal oxide to a metal bypassing an electric current in the molten salt bath between the anode and the coated cathode.Type: GrantFiled: December 28, 1994Date of Patent: February 20, 1996Assignee: Aluminum Company of AmericaInventor: Siba P. Ray
-
Patent number: 5415742Abstract: A process for electrowinning metal in a low temperature melt is disclosed. The process utilizes an inert anode for the production of metal such as aluminum using low surface area anodes at high current densities.Type: GrantFiled: October 15, 1993Date of Patent: May 16, 1995Assignee: Aluminum Company of AmericaInventors: Alfred F. La Camera, Kathleen M. Tomaswick, Siba P. Ray, Donald P. Ziegler
-
Patent number: 5279715Abstract: A process for electrowinning metal in a low temperature melt is disclosed. The process utilizes an inert anode for the production of metal such as aluminum using low surface area anodes at high current densities.Type: GrantFiled: September 17, 1991Date of Patent: January 18, 1994Assignee: Aluminum Company of AmericaInventors: Alfred F. La Camera, Kathleen M. Tomaswick, Siba P. Ray, Donald P. Ziegler
-
Patent number: 5137867Abstract: An in situ formed superconducting cermet comprising an interwoven matrix of a superconducting ceramic and a noble metal and a method of making same are disclosed.Type: GrantFiled: October 16, 1987Date of Patent: August 11, 1992Assignee: Aluminum Company of AmericaInventors: Siba P. Ray, C. Norman Cochran, William E. Libent
-
Patent number: 5098871Abstract: Disclosed is a method of forming an improved ceramic matrix composite wherein there is provided a slurry comprised of aluminum oxide, boron oxide and an organic binder suspended in a liquid, and combining the slurry with fibers. The aluminum oxide and boron oxide are capable of reacting to form aluminum borate. The improvement comprises providing the fibers with a coating which forms a stable interface between the fibers and the aluminum borate.Type: GrantFiled: December 13, 1990Date of Patent: March 24, 1992Assignee: Aluminum Company of AmericaInventor: Siba P. Ray
-
Patent number: 5053364Abstract: Disclosed is a high strength aluminum borate ceramic matrix composite product and a method of making the same which comprises providing a slurry of aluminum oxide, boron oxide and organic or aqueous binder, the aluminum oxide and boron oxide capable of reacting to form aluminum borate. The slurry is introduced to a body, e.g., web of ceramic fibers, to provide an infiltrated web. After removing liquid and organic binder from the infiltrated web, it is sintered to react the aluminum oxide and boron oxide to form a ceramic matrix composite comprised of aluminum borate and said web of ceramic fibers. The reaction causes a volume expansion which aids in filling or removal of pores or voids resulting from the removal of organic binder.Type: GrantFiled: June 12, 1989Date of Patent: October 1, 1991Assignee: Aluminum Company of AmericaInventor: Siba P. Ray
-
Patent number: 4892861Abstract: Disclosed is a cermet exhibiting superconducting properties with improved mechanical properties comprising a mixture of a superconducting ceramic and one or more metals, the cermet resulting from liquid phase sintering at a temperature at which one of the metals is molten and below the melting temperature of the superconducting ceramic.Type: GrantFiled: August 14, 1987Date of Patent: January 9, 1990Assignee: Aluminum Company of AmericaInventor: Siba P. Ray
-
Patent number: 4804642Abstract: Disclosed is an aluminum borate base ceramic composite comprised of a metal compound and a composition having the formula Al.sub.x B.sub.y O.sub.z.Type: GrantFiled: November 28, 1986Date of Patent: February 14, 1989Assignee: Aluminum Company of AmericaInventor: Siba P. Ray