Abstract: A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.

Abstract: A joint for use in electrochemical devices, such as solid oxide fuel cells (SOFCs), oxygen separators, and hydrogen separators, that will maintain a hermetic seal at operating temperatures of greater than 600° C., despite repeated thermal cycling excess of 600° C. in a hostile operating environment where one side of the joint is continuously exposed to an oxidizing atmosphere and the other side is continuously exposed to a wet reducing gas. The joint is formed of a metal part, a ceramic part, and a flexible gasket. The flexible gasket is metal, but is thinner and more flexible than the metal part.

Abstract: A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.

Abstract: The present invention provides novel compositions that find advantageous use in making electrodes for electrochemical cells. Also provided are electrochemical devices that include active oxygen reduction electrodes, such as solid oxide fuel cells, sensors, pumps and the like. The compositions comprises a copper-substituted ferrite perovskite material. The invention also provides novel methods for making and using the electrode compositions and solid oxide fuel cells and solid oxide fuel cell assemblies having cathodes comprising the compositions.

Abstract: The present invention provides novel compositions that find advantageous use in making electrodes for electrochemical cells. Also provided are electrochemical devices that include active oxygen reduction electrodes, such as solid oxide fuel cells, sensors, pumps and the like. The compositions comprises a copper-substituted ferrite perovskite material. The invention also provides novel methods for making and using the electrode compositions and solid oxide fuel cells and solid oxide fuel cell assemblies having cathodes comprising the compositions.

Abstract: A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.

Abstract: A seal formed between a metal part and a second part that will remain gas tight in high temperature operating environments which experience frequent thermal cycling, which is particularly useful as an insulating joint in solid oxide fuel cells. A first metal part is attached to a reinforcing material. A glass forming material in the positioned in between the first metal part and the second part, and a seal is formed between the first metal part and the second part by heating the glass to a temperature suitable to melt the glass forming materials. The glass encapsulates and bonds at least a portion of the reinforcing material, thereby adding tremendous strength to the overall seal. A ceramic material may be added to the glass forming materials, to assist in forming an insulating barrier between the first metal part and the second part and to regulating the viscosity of the glass during the heating step.

Abstract: High-temperature air braze filler materials composed of various ternary metal alloys are described. Noble metals (M) are added as a ternary constituent to a silver-copper oxide (Ag—CuOx) system. The silver (Ag) component is directly substituted with the noble metal to form a series of alloys. Addition of the noble metal increases the solidus and liquidus temperatures of the resulting air braze filler metals and increases temperatures under which seals and other sealing components formed from these filler metals can be employed.

Abstract: A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.

Abstract: In assembling an SOFC fuel cell stack from a plurality of cassettes, the mounting plate of one cassette is attached to, and insulated from, the separator plate of the next-adjacent cassette by a peripheral dielectric seal consisting of a ceramic coating and a metal braze. Materials suitable for the ceramic coating include yttrium stabilized zirconia (YSZ), zirconia toughened alumina, magnesium silicates such as the mineral forsterite, magnesium aluminates, magnesium aluminosilicates and lanthanum zirconate. The ceramic coating may be applied to the cassette's outer surface in known fashion as by physical vapor deposition, chemical vapor deposition, sputtering, and various methods of plasma spray. An underlayer of alumina may also be used to provide a redundant layer of electrical insulation.

Abstract: A method of joining metal and ceramic parts, wherein an alumina forming metal part and a ceramic part are provided. A braze material in placed between the alumina forming metal part and the ceramic part, and the combination is then heated in an oxidizing atmosphere, preferably in air at a temperature of between 500° C. and 1300° C. The alumina forming metal parts are selected from the group consisting of high temperature stainless steels, such as Durafoil (alpha-4), Fecralloy, Alumina-coated 430 stainless steel and Crofer-22APU, and high temperature superalloys such as Haynes 214, Nicrofer 6025, and Ducraloy. The braze material is selected as a metal oxide-noble metal mixture, preferably Ag—CuO, Ag—V2O5, and Pt—Nb2O5, and more preferably between 30.65 to 100 mole % Ag in CuO.

Abstract: A method of joining metal and ceramic parts, wherein an alumina forming metal part and a ceramic part are provided. A braze material in placed between the alumina forming metal part and the ceramic part, and the combination is then heated in an oxidizing atmosphere, preferably in air at a temperature of between 500° C. and 1300° C. The alumina forming metal parts are selected from the group consisting of high temperature stainless steels, such as Durafoil (alpha-4), Fecralloy, Alumina-coated 430 stainless steel and Crofer-22APU, and high temperature superalloys such as Haynes 214, Nicrofer 6025, and Ducraloy. The braze material is selected as a metal oxide-noble metal mixture, preferably Ag—CuO, Ag—V2O5, and Pt—Nb2O5, and more preferably between 30.65 to 100 mole % Ag in CuO.