Patents by Inventor Timothy P. Weihs
Timothy P. Weihs 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).
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Patent number: 7297626Abstract: A Ni2Si-nSiC Ohmic contact is formed by pulsed laser ablation deposition (PLD) of Ni2Si source target deposited on a n-SiC substrate or SiC substrate wafer with SiC epilayer. The Ni2Si Ohmic contact on n-SiC was rapid thermal annealed at 950° C. for 30 s in a N2 ambient. The resultant Ohmic contact is characterized by excellent current-voltage (I-V) characteristics, an abrupt void free contact-SiC interface, retention of the PLD as-deposited contact layer width, smooth surface morphology, and absence of residual carbon within the contact layer or at the interface. The detrimental effects of contact delamination due to stress associated with interfacial voiding; and wire bond failure, non-uniformity of current flow and SiC polytype alteration due to extreme surface roughness; have been eliminated as has electrical instability associated with carbon inclusions at the contact-SiC interface, after prolonged high temperature and power device operation.Type: GrantFiled: February 17, 2006Date of Patent: November 20, 2007Assignee: United States of America as Represented by the Secretary of the ArmyInventors: Melanie W. Cole, Timothy P. Weihs
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Patent number: 7143568Abstract: Embodiments of the invention include a method for sealing a container. The method includes, providing at least two components of the container, positioning a crushable material between the at least two components, positioning a reactive multilayer material between the at least two components, deforming the crushable material so as to form a seal between the at least two components, chemically transforming the reactive multilayer material so as to join the at least two components.Type: GrantFiled: October 31, 2005Date of Patent: December 5, 2006Assignee: Reactive Nano Technologies, Inc.Inventors: David Peter Van Heerden, Dale Deger, Timothy P. Weihs, Omar M. Knio
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Patent number: 7121402Abstract: Embodiments of the invention include a method for sealing a container. The method includes, providing at least two components of the container, positioning a crushable material between the at least two components, positioning a reactive multilayer material between the at least two components, deforming the crushable material so as to form a seal between the at least two components, chemically transforming the reactive multilayer material so as to join the at least two components.Type: GrantFiled: April 1, 2004Date of Patent: October 17, 2006Assignee: Reactive Nano Technologies, IncInventors: David Peter Van Heerden, Dale Deger, Timothy P. Weihs, Omar M. Knio
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Patent number: 6991856Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt or soften the joining material, which upon cooling will form a strong bond, joining two or more bulk materials.Type: GrantFiled: September 20, 2002Date of Patent: January 31, 2006Assignee: Johns Hopkins UniversityInventors: Timothy P. Weihs, Michael Reiss, Omar Knio, Albert Joseph Swiston, Jr., David van Heerden, Todd Hufnagel
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Patent number: 6991855Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials.Type: GrantFiled: January 21, 2004Date of Patent: January 31, 2006Assignee: Johns Hopkins UniversityInventors: Timothy P. Weihs, Omar Knio, Michael Reiss, David van Heerden
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Patent number: 6863992Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials.Type: GrantFiled: January 21, 2004Date of Patent: March 8, 2005Assignee: Johns Hopkins UniversityInventors: Timothy P. Weihs, Omar Knio, Michael Reiss, David van Heerden
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Publication number: 20040247931Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials.Type: ApplicationFiled: January 21, 2004Publication date: December 9, 2004Inventors: Timothy P. Weihs, Todd Hufnagel, Omar Knio, Michael Reiss, David van Heerden, Howard Feldmesser
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Publication number: 20040247930Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials.Type: ApplicationFiled: January 21, 2004Publication date: December 9, 2004Inventors: Timothy P. Weihs, Todd Hufnagel, Omar Knio, Michael Reiss, David van Heerden, Howard Feldmesser
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Publication number: 20040200736Abstract: Embodiments of the invention include a method for sealing a container. The method includes, providing at least two components of the container, positioning a crushable material between the at least two components, positioning a reactive multilayer material between the at least two components, deforming the crushable material so as to form a seal between the at least two components, chemically transforming the reactive multilayer material so as to join the at least two components.Type: ApplicationFiled: April 1, 2004Publication date: October 14, 2004Inventors: David Peter Van Heerden, Dale Deger, Timothy P. Weihs, Omar M. Knio
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Publication number: 20040149813Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials.Type: ApplicationFiled: January 21, 2004Publication date: August 5, 2004Inventors: Timothy P. Weihs, Todd Hufnagel, Omar Knio, Michael Reiss, David van Heerden, Howard Feldmesser
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Publication number: 20040151939Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials.Type: ApplicationFiled: January 21, 2004Publication date: August 5, 2004Inventors: Timothy P. Weihs, Todd Hufnagel, Omar Knio, Michael Reiss, David van Heerden, Howard Feldmesser
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Publication number: 20040149373Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials.Type: ApplicationFiled: January 21, 2004Publication date: August 5, 2004Inventors: Timothy P. Weihs, Todd Hufnagel, Omar Knio, Michael Reiss, David van Heerden, Howard Feldmesser
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Publication number: 20040149372Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials.Type: ApplicationFiled: January 21, 2004Publication date: August 5, 2004Inventors: Timothy P. Weihs, Todd Hufnagel, Omar Knio, Michael Reiss, David van Heerden, Howard Feldmesser
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Patent number: 6736942Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials.Type: GrantFiled: May 1, 2001Date of Patent: May 18, 2004Assignee: Johns Hopkins UniversityInventors: Timothy P. Weihs, Todd Hufnagel, Omar Knio, Michael Reiss, David van Heerden, Howard Feldmesser
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Publication number: 20030164289Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt or soften the joining material, which upon cooling will form a strong bond, joining two or more bulk materials.Type: ApplicationFiled: September 20, 2002Publication date: September 4, 2003Applicant: JOHNS HOPKINS UNIVERSITYInventors: Timothy P. Weihs, Michael Reiss, Omar Knio, Albert Joseph Swiston, David van Heerden, Howard Feldmesser, Todd Hufnagel
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Patent number: 6596101Abstract: Preferred embodiments of the invention provide new nanostructured materials and methods for preparing nanostructured materials having increased tensile strength and ductility, increased hardness, and very fine grain sizes making such materials useful for a variety of applications such as rotors, electric generators, magnetic bearings, aerospace and many other structural and nonstructural applications. The preferred nanostructured materials have a tensile yield strength from at least about 1.9 to about 2.3 GPa and a tensile ductility from at least 1%. Preferred embodiments of the invention also provide a method of making a nanostructured material comprising melting a metallic material, solidifying the material, deforming the material, forming a plurality of dislocation cell structures, annealing the deformed material at a temperature from about 0.30 to about 0.70 of its absolute melting temperature, and cooling the material.Type: GrantFiled: October 3, 2001Date of Patent: July 22, 2003Assignee: Johns Hopkins UniversityInventors: Timothy P. Weihs, Robert Cammarata, Chia-Ling Chien, Changhe Shang
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Patent number: 6534194Abstract: In accordance with the invention a reactive multilayer foil is fabricated by providing an assembly (stack or multilayer) of reactive layers, inserting the assembly into a jacket, deforming the jacketed assembly to reduce its cross sectional area, flattening the jacketed assembly into a sheet, and then removing the jacket. Advantageously, the assembly is wound into a cylinder before insertion into the jacket, and the jacketed assembly is cooled to a temperature below 100° C. during deforming. The resulting multilayer foil is advantageous as a freestanding reactive foil for use in bonding, ignition or propulsion.Type: GrantFiled: May 1, 2001Date of Patent: March 18, 2003Assignee: Johns Hopkins UniversityInventors: Timothy P. Weihs, Michael Reiss
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Publication number: 20030019096Abstract: In accordance with the invention, a magnetic device is made by providing magnetic sheet layers with reactive joining materials that will react to join the layers into a unitary body. The joining materials are reacted, and the device is formed. In a preferred embodiment, the magnetic material is a soft magnetic material such as FeCo alloy, and the reactive joining materials are aluminum and FeCoOx which react to form nonconducting alumina layers between magnetic regions.Type: ApplicationFiled: June 24, 2002Publication date: January 30, 2003Inventor: Timothy P. Weihs
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Publication number: 20020182436Abstract: Reactive foils and their uses are provided as localized heat sources useful, for example, in ignition, joining and propulsion. An improved reactive foil is preferably a freestanding multilayered foil structure made up of alternating layers selected from materials that will react with one another in an exothermic and self-propagating reaction. Upon reacting, this foil supplies highly localized heat energy that may be applied, for example, to joining layers, or directly to bulk materials that are to be joined. This foil heat-source allows rapid bonding to occur at room temperature in virtually any environment (e.g., air, vacuum, water, etc.). If a joining material is used, the foil reaction will supply enough heat to melt the joining materials, which upon cooling will form a strong bond, joining two or more bulk materials. If no joining material is used, the foil reaction supplies heat directly to at least two bulk materials, melting a portion of each bulk, which upon cooling, form a strong bond.Type: ApplicationFiled: April 18, 2002Publication date: December 5, 2002Inventors: Timothy P. Weihs, Todd Hufnagel, Omar Knio, Michael Reiss, David van Heerden, Howard Feldmesser
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Publication number: 20020069944Abstract: Preferred embodiments of the invention provide new nanostructured materials and methods for preparing nanostructured materials having increased tensile strength and ductility, increased hardness, and very fine grain sizes making such materials useful for a variety of applications such as rotors, electric generators, magnetic bearings, aerospace and many other structural and nonstructural applications. The preferred nanostructured materials have a tensile yield strength from at least about 1.9 to about 2.3 GPa and a tensile ductility from at least 1%. Preferred embodiments of the invention also provide a method of making a nanostructured material comprising melting a metallic material, solidifying the material, deforming the material, forming a plurality of dislocation cell structures, annealing the deformed material at a temperature from about 0.30 to about 0.70 of its absolute melting temperature, and cooling the material.Type: ApplicationFiled: October 3, 2001Publication date: June 13, 2002Inventors: Timothy P. Weihs, Robert Cammarata, Chia-Ling Chien, Changhe Shang