Patents by Inventor Detlev Stoever

Detlev Stoever 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: 8916091
    Abstract: Disclosed is a method for producing semi-finished products from a shape memory alloy, particularly an NiTi shape memory alloy, wherein a powder is first produced from a shape memory alloy, and subsequently the powder is divided into a coarse fraction and a fine fraction in a separating cut T. While the fine fraction is required, in particular, for the production of a first semi-finished product, employing the metal injection molding (MIM) method, the coarse fraction can be used for the production of a second semi-finished product, employing the hot isostatic pressing (HIP) method. The advantages of the invention can be summarized as follows. The MIM method for producing semi-finished products from a shape memory alloy is qualitatively improved and more cost-effective to implement if the coarse fraction that is typically obtained during powder production, but not used for the MIM process, can advantageously be supplied to a further process, in this case the HIP process.
    Type: Grant
    Filed: August 27, 2008
    Date of Patent: December 23, 2014
    Assignee: Forschungszentrum Juelich GmbH
    Inventors: Manuel Koehl, Martin Bram, Berthold Coenen, Hans Peter Buchkremer, Detlev Stoever
  • Patent number: 8518605
    Abstract: The invention relates to an anode for a high-temperature fuel cell having an anode substrate and/or a functional anode layer, comprising a porous ceramic structure having a first predominantly electron-conducting phase with the general empirical formula Sr1-xLnxTiO3 wherein Ln=Y, Gd to Lu and 0.03<x<0.2, and having a second predominantly ion-conducting phase component comprising yttrium or scandium-stabilized zirconium dioxide (YSZ or ScSZ). In the anode substrate and/or the functional anode layer, the ratio by volume of the first phase to the second phase ranges from 80:20 to 50:50, and particularly from 70:30 to 60:40. The porosity of the entire anode ranges between 15 and 50% by volume. The anode additionally comprises a catalyst in the amount of no more than 15% of the total volume, which is disposed on the surface of the pores of the ceramic structure.
    Type: Grant
    Filed: June 26, 2007
    Date of Patent: August 27, 2013
    Assignee: Forschungszentrum Juelich GmbH
    Inventors: Qingxi Fu, Frank Tietz, Hans-Peter Buchkremer, Detlev Stoever
  • Publication number: 20130216938
    Abstract: The material according to the invention is based on a material having the composition Ln6WO12 with a defect fluorite structure in which the cations, at least partially, have been substituted in a defined manner in the A and/or B position. It has the following composition: Ln1-xAx)6(W1-yBy)zO12-? where Ln=an element from the group (La, Pr, Nd, Sm), A=at least one element from the group (La, Ce, Pr, Nd, Eu, Gd, Tb, Er, Yb, Ca, Mg, Sr, Ba, Th, In, Pb), B=at least one element from the group (Mo, Re, U, Cr, Nb), 0?x?0.7 and 0?y?0.5, wherein, however, either x or y>0, 1.00?z?1.25 and 0???0.3. The mixed proton-electron conducting material exhibits an improved mixed conductivity, good chemical stability as well as good sintering properties, and can be used in particular as a material for a hydrogen-separating membrane or as a electrolyte at higher temperatures.
    Type: Application
    Filed: June 28, 2011
    Publication date: August 22, 2013
    Applicants: UNIVERSIDAD POLITECNICA DE VALENCIA, FORSCHUNGSZENTRUM JULICH GMBH
    Inventors: Wilhelm Albert Meulenberg, Mariya Ivanova, Hans Peter Buchkremer, Detlev Stoever, Jose Manuel Serra Alfaro, Sonia Escolastico
  • Publication number: 20130196141
    Abstract: Provided is a method for internally coating the pores of a porous functional coating made of a base material with a hardening material that reduces the diffusion of the base material and/or the reactivity of the base material with the environment thereof. The hardening material is deposited from the gas phase onto the interior surfaces of the pores. It was recognized that by depositing hardening material from the gas phase, it can be introduced much deeper into the pore system of the functional coating than had been possible according to the prior art. This applies in particular when the hardening material is not itself introduced into the pore s stem, but rather one or two precursors thereof, and from said precursors the actual hardening material forms at the internal surfaces of the pores.
    Type: Application
    Filed: April 5, 2011
    Publication date: August 1, 2013
    Inventors: Robert Vassen, Frank Vondahlen, Doris Sebold, Daniel Emil Mack, Georg Mauer, Detlev Stoever
  • Patent number: 8486184
    Abstract: A composite membrane for selective gas separation, comprises a layer system having a continuously porous, mechanically stable carrier layer, which has an average pore size in the ?m range, further having at least one continuously porous intermediate layer, which is disposed on the carrier layer and has an average pore size in the range of 2 to 200 nm, and further having a gastight functional layer, which is disposed on the intermediate layer and is made of a mixed-conductive material having a maximum layer thickness of 1 ?m. The carrier layer comprises a structural ceramic, a metal, or a cermet and has a layer thickness of no more than 1 mm. The intermediate layer is present with a total layer thickness of no more than 100 ?m and has an average pore size in the range of 10 to 100 nm. The functional layer comprises a perovskite, a fluorite, or a material having a K2NiF4 structure, such as La1-xSrxCo1-yFeyO3-8 (LSCF).
    Type: Grant
    Filed: February 21, 2009
    Date of Patent: July 16, 2013
    Assignee: Forschungszentrum Juelich GmbH
    Inventors: Stefan Baumann, Jose Manuel Serra Alfaro, Wilhelm Albert Meulenberg, Hans-Peter Buchkremer, Detlev Stoever
  • Publication number: 20110244216
    Abstract: Disclosed is a method for producing a coating system on a component, wherein at least one coating is deposited on the component by way of atmospheric plasma spraying (APS) and at least one further coating is deposited by way of suspension plasma spraying (SPS). The coatings are particularly advantageously deposited in the sequence of APS+SPS or APS+SPS+APS or APS+SPS+erosion coating. These sequences of coatings applied in this way usually have an effect providing a first porous coating and a second porous coating disposed thereon, wherein the porosity of the second coating is greater than that of the first coating, and wherein the reflectivity is greater than that of the first coating.
    Type: Application
    Filed: January 29, 2009
    Publication date: October 6, 2011
    Inventors: Alexandra Meyer, Holger Kassner, Robert Vassen, Detlev Stoever, Jose-Luis Marques-Lopez
  • Patent number: 7998601
    Abstract: A method produces thermal barrier coatings that adhere to components even at high temperatures and temperatures that change frequently. A gas-tight glass-metal composite coating is applied to the component and annealed. The corroded part of the gas-tight coating is then removed, and a second, porous coating is applied. The second coating can comprise a ceramic, in particular yttrium-stabilized zirconium oxide. A thermal barrier coating is provided that is a composite made of a gas-tight glass-metal composite coating and another porous coating disposed thereover. Because the boundary volume of the composite coating is partly crystallized to the other coating, superior adhesion within the composite is achieved. Thus, it is in particular possible to produce a composite made of silicate glass-metal composite coatings and yttrium-stabilized zirconium oxide that are temperature-stable for extended periods of time.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: August 16, 2011
    Assignee: Forschungszentrum Juelich GmbH
    Inventors: Daniel Emil Mack, Sonja-Michaela Gross, Robert Vassen, Detlev Stoever
  • Publication number: 20110020192
    Abstract: The invention relates to a composite membrane for selective gas separation, comprising a layer system having a through-and-through porous, mechanically stable carrier layer, which has an average pore size in the ?m range, further having at least one through-and-through porous intermediate layer, which is disposed on the carrier layer and has an average pore size in the range between 2 and 200 nm, and further having a gas-tight functional layer, which is disposed on the intermediate layer and is made of mixed-conductive material having a maximum layer thickness of 1 ?m. The carrier layer comprises structural ceramics, a metal or a cermet and has a layer thickness of no more than 1 mm. The intermediate layer is present in a total layer thickness of no more than 100 ?m and has an average pore size in the range of 10 and 100 nm. The functional layer comprises a perovskite, a fluorite, or a material having a K2NiF4structure, such as La1-xSrxCo1-yFeyO3-?(LSCF).
    Type: Application
    Filed: February 21, 2009
    Publication date: January 27, 2011
    Applicant: FORSCHUNGSZENTRUM JÜLICH GMBH
    Inventors: Stefan Baumann, Jose Manuel Serra Alfaro, Wilhelm Albert Meulenberg, Hans-Peter Buchkremer, Detlev Stoever
  • Publication number: 20100310407
    Abstract: Disclosed is a method for producing semi-finished products from a shape memory alloy, particularly an NiTi shape memory alloy, wherein a powder is first produced from a shape memory alloy, and subsequently the powder is divided into a coarse fraction and a fine fraction in a separating cut T. While the fine fraction is required, in particular, for the production of a first semi-finished product, employing the metal injection molding (MIM) method, the coarse fraction can be used for the production of a second semi-finished product, employing the hot isostatic pressing (HIP) method. The advantages of the invention can be summarized as follows. The MIM method for producing semi-finished products from a shape memory alloy is qualitatively improved and more cost-effective to implement if the coarse fraction that is typically obtained during powder production, but not used for the MIM process, can advantageously be supplied to a further process, in this case the HIP process.
    Type: Application
    Filed: August 27, 2008
    Publication date: December 9, 2010
    Inventors: Manuel Koehl, Martin Bram, Berthold Coenen, Hans Peter Buchkremer, Detlev Stoever
  • Publication number: 20100028757
    Abstract: The invention relates to an anode for a high-temperature fuel cell having an anode substrate and/or a functional anode layer, comprising a porous ceramic structure having a first predominantly electron-conducting phase with the general empirical formula Sr1-xLnxTiO3 wherein Ln=Y, Gd to Lu and 0.03<x<0.2, and having a second predominantly ion-conducting phase component comprising yttrium or scandium-stabilized zirconium dioxide (YSZ or ScSZ). In the anode substrate and/or the functional anode layer, the ratio by volume of the first phase to the second phase ranges from 80:20 to 50:50, and particularly from 70:30 to 60:40. The porosity of the entire anode ranges between 15 and 50% by volume. The anode additionally comprises a catalyst in the amount of no more than 15% of the total volume, which is disposed on the surface of the pores of the ceramic structure.
    Type: Application
    Filed: June 26, 2007
    Publication date: February 4, 2010
    Applicant: FORSCHUNGSZENTRUM JÜLICH GMBH
    Inventors: Qingxi Fu, Frank Tietz, Hans-Peter Buchkremer, Detlev Stoever
  • Patent number: 7585575
    Abstract: A heat-insulating layer has a melting point above 2500° C., a thermal expansion coefficient in excess of 8×10?6 K?1, and a sintering temperature greater than 1400° C. This material has a perovskite structure of the general formula A1+r(B?1/2+xB?1/2+y)O3+z in which: A=at least one element of the group (Ba, Sr, Ca, Be), B?=at least one element of the group (Al, La, Nd, Gd, Er, Lu, Dy, Tb), B?=at least one element of the group (Ta, Nb), and 0.1<r,x,y,z<0.1.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: September 8, 2009
    Assignee: Forschungszentrum Julich GmbH
    Inventors: Robert Vassen, Sigrid Schwartz-Lueckge, Wolfgang Jungen, Detlev Stoever
  • Publication number: 20090110904
    Abstract: A method produces thermal barrier coatings that adhere to components even at high temperatures and temperatures that change frequently. A gas-tight glass-metal composite coating is applied to the component and annealed. The corroded part of the gas-tight coating is then removed, and a second, porous coating is applied. The second coating can comprise a ceramic, in particular yttrium-stabilized zirconium oxide. A thermal barrier coating is provided that is a composite made of a gas-tight glass-metal composite coating and another porous coating disposed thereover. Because the boundary volume of the composite coating is partly crystallized to the other coating, superior adhesion within the composite is achieved. Thus, it is in particular possible to produce a composite made of silicate glass-metal composite coatings and yttrium-stabilized zirconium oxide that are temperature-stable for extended periods of time.
    Type: Application
    Filed: October 17, 2006
    Publication date: April 30, 2009
    Inventors: Daniel Emil Mack, Sonja-Michaela Gross, Robert Vassen, Detlev Stoever
  • Patent number: 7445851
    Abstract: A heat-insulating layer system for a metallic structural component, especially for a structural component of a gas turbine such as an aircraft engine, includes an adhesion promoting layer (12), an inner contact layer (14), and an outer cover layer (15) , whereby the adhesion promoting layer (12). is disposed on a surface (11) of the gas turbine structural component (10). The inner contact layer (14) is formed of a zirconium oxide partially stabilized with yttrium or yttrium oxide, and the outer cover layer (15) is formed of a material that consists of at least one component with at least one phase, which stoichiometrically comprises 1 to 80 Mol-% Mx2O3, 0.5 to 80 Mol-% MyO and Al2O3 as a remainder with incidental impurities, wherein Mx is selected from the elements chromium and barium or mixtures thereof, and wherein My is selected from the alkaline earth metals, the transition metals and the rare earths or mixtures thereof.
    Type: Grant
    Filed: May 24, 2005
    Date of Patent: November 4, 2008
    Assignees: MTU Aero Engines GmbH, Forschungszentrum Juelich GmbH
    Inventors: Christian Friedrich, Wolfgang Wachter, Detlev Stoever, Gerhard Pracht, Robert Vassen, Bilge Saruhan-Brings, Claus-Juergen Kroeder, Uwe Schulz
  • Publication number: 20080220310
    Abstract: Anode-supported high-temperature fuel cells with a substrate and an anode of stabilised zirconium dioxide and metallic nickel can be destroyed by air penetrating on the fuel gas side. Reoxidation causes the volume of the nickel in the anode to change. The resultant mechanical stresses may destroy the gas-impermeable electrolyte. The invention provides oxygen scavengers that can be produced at low cost for the anode, which more effectively bind the oxygen that penetrates on the fuel gas side than oxygen scavengers according to the prior art.
    Type: Application
    Filed: August 5, 2006
    Publication date: September 11, 2008
    Applicant: Forschungszentrum Juelich GmbH
    Inventors: Josef Mertens, Norbert Menzler, Hans Peter Buchkremer, Detlev Stoever
  • Publication number: 20080206606
    Abstract: A cathode for high-temperature fuel cell, comprising a layer of porous particles applied on a sintered electrolyte, the layer having a surface area of 15 to 900 m2 per gram and the average size of the porous particles do not exceed 30 nm and a method for preparing the same.
    Type: Application
    Filed: April 27, 2006
    Publication date: August 28, 2008
    Inventors: Jose Manuel Serra Alfaro, Sevn Uhlenbruck, Hans-Peter Buchkremer, Detlev Stoever
  • Publication number: 20070248764
    Abstract: The invention relates to a heat-insulating layer system for metallic structural components, especially for structural components of a gas turbine such as an aircraft engine. The heat-insulating layer system (13) comprises an inner contact layer (14) and an outer cover layer (15), whereby the inner contact layer (14) is applied onto a surface (11) of a gas turbine structural component (10) with intermediate arrangement of an adhesion promoting layer (12). According to the invention, the inner contact layer (14) is formed of a zirconium oxide partially stabilized with yttrium or yttrium oxide, the outer cover layer (15) is formed of lanthanum hexaaluminate.
    Type: Application
    Filed: May 24, 2005
    Publication date: October 25, 2007
    Applicants: MTU AERO ENGINES GMBH, FORSCHUNGSZENTRUM JUELICH GMBH
    Inventors: Christian Friedrich, Wolfgang Wachter, Detlev Stoever, Gerhard Pracht, Robert Vassen, Bilge Saruhan-Brings, Claus-Juergen Kroeder, Uwe Schulz
  • Publication number: 20040126637
    Abstract: A combination of a plasma spraying process and a vacuum slip casting process is carried out. By combining these two processes, which can each be carried out without difficulty, it is surprisingly possible to achieve good electrolyte layers. Therefore, it is possible to construct a fuel cell system using coated tubes in a bundled arrangement, the tubes being electrically connected in series and operated as a fuel cell generator in power units of between 100 kW and a few MW.
    Type: Application
    Filed: May 23, 2003
    Publication date: July 1, 2004
    Inventors: Gerard Barbezat, Hans Peter Buchkremer, Robert Fleck, Michael Loch, Norbert Heribert Menzler, Detlev Stoever