Abstract: Some embodiments provide a waste heat recovery apparatus including an exhaust tube having a cylindrical outer shell configured to contain a flow of exhaust fluid; a first heat exchanger extending through a first region of the exhaust tube, the first heat exchanger in thermal communication with the cylindrical outer shell; a second region of the exhaust tube extending through the exhaust tube, the second region having a low exhaust fluid pressure drop; an exhaust valve operatively disposed within the second region and configured to allow exhaust fluid to flow through the second region only when a flow rate of the exhaust fluid becomes great enough to result in back pressure beyond an allowable limit; and a plurality of thermoelectric elements in thermal communication with an outer surface of the outer shell.

Abstract: Some embodiments provide a waste heat recovery apparatus including an exhaust tube having a cylindrical outer shell configured to contain a flow of exhaust fluid; a first heat exchanger extending through a first region of the exhaust tube, the first heat exchanger in thermal communication with the cylindrical outer shell; a second region of the exhaust tube extending through the exhaust tube, the second region having a low exhaust fluid pressure drop; an exhaust valve operatively disposed within the second region and configured to allow exhaust fluid to flow through the second region only when a flow rate of the exhaust fluid becomes great enough to result in back pressure beyond an allowable limit; and a plurality of thermoelectric elements in thermal communication with an outer surface of the outer shell.

Abstract: A method for bonding an LED assembly 71 or other electronic package 31 to a substrate PCB containing a heat-sink 52, which utilizes layers of reactive multilayer foil 51 disposed between contacts 32, 34 of the electronic package 31 and the associated contact pads 55 on the supporting substrate PCB. By initiating an exothermic reaction in the reactive multilayer foil 51, together with an application of pressure, sufficient heat is generated between the contacts 32, 34 and the associated contact pads 55 to melt adjacent bonding material 54 to obtain good electrically and thermally conductive bonds between the contacts 32, 34 and contact pads 55 without thermally damaging the electronic package 31, heat-sensitive components 35 associated with the electronic package 31, or other the supporting substrate PCB.

Abstract: A method for bonding an LED assembly (71) or other electronic package (31) to a substrate PCB containing a heat-sink (52), which utilizes layers of reactive multilayer foil (51) disposed between contacts (32, 34) of the electronic package 31 and the associated contact pads (55) on the supporting substrate PCB. By initiating an exothermic reaction in the reactive multilayer foil (51), together with an application of pressure, sufficient heat is generated between the contacts (32, 34) and the associated contact pads (55) to melt adjacent bonding material (54) to obtain good electrically and thermally conductive bonds between the contacts 32, 34 and contact pads (55) without thermally damaging the electronic package (31), heat-sensitive components (35) associated with the electronic package (31), or other the supporting substrate PCB.

Abstract: Some embodiments provide a waste heat recovery apparatus including an exhaust tube having a cylindrical outer shell configured to contain a flow of exhaust fluid; a first heat exchanger extending through a first region of the exhaust tube, the first heat exchanger in thermal communication with the cylindrical outer shell; a second region of the exhaust tube extending through the exhaust tube, the second region having a low exhaust fluid pressure drop; an exhaust valve operatively disposed within the second region and configured to allow exhaust fluid to flow through the second region only when a flow rate of the exhaust fluid becomes great enough to result in back pressure beyond an allowable limit; and a plurality of thermoelectric elements in thermal communication with an outer surface of the outer shell.

Abstract: Some embodiments provide a waste heat recovery apparatus including an exhaust tube having a cylindrical outer shell configured to contain a flow of exhaust fluid; a first heat exchanger extending through a first region of the exhaust tube, the first heat exchanger in thermal communication with the cylindrical outer shell; a second region of the exhaust tube extending through the exhaust tube, the second region having a low exhaust fluid pressure drop; an exhaust valve operatively disposed within the second region and configured to allow exhaust fluid to flow through the second region only when a flow rate of the exhaust fluid becomes great enough to result in back pressure beyond an allowable limit; and a plurality of thermoelectric elements in thermal communication with an outer surface of the outer shell.

Abstract: Applicants have discovered that electrostatic discharge (ESD) may, in some circumstances, result in current densities sufficient to ignite unprotected reactive composite materials. They have further discovered that a reactive composite material (RCM) can be protected from ESD ignition without adversely affecting the desirable properties of the RCM by the application of conducting and/or insulating materials at appropriate locations on the RCM. Thus ESD-protected RCM structures can be designed for such sensitive applications as ignition of propellants, generation of light bursts, and structural materials for equipment that may require controlled self-destruction.

Abstract: A method for bonding an LED assembly (71) or other electronic package (31) to a substrate PCB containing a heat-sink (52), which utilizes layers of reactive multilayer foil (51) disposed between contacts (32, 34) of the electronic package 31 and the associated contact pads (55) on the supporting substrate PCB. By initiating an exothermic reaction in the reactive multilayer foil (51), together with an application of pressure, sufficient heat is generated between the contacts (32, 34) and the associated contact pads (55) to melt adjacent bonding material (54) to obtain good electrically and thermally conductive bonds between the contacts 32, 34 and contact pads (55) without thermally damaging the electronic package (31), heat-sensitive components (35) associated with the electronic package (31), or other the supporting substrate PCB.

Abstract: Applicants have discovered that electrostatic discharge (ESD) may, in some circumstances, result in current densities sufficient to ignite unprotected reactive composite materials. They have further discovered that a reactive composite material (RCM) can be protected from ESD ignition without adversely affecting the desirable properties of the RCM by the application of conducting and/or insulating materials at appropriate locations on the RCM. Thus ESD-protected RCM structures can be designed for such sensitive applications as ignition of propellants, generation of light bursts, and structural materials for equipment that may require controlled self-destruction.

Abstract: Some embodiments provide a waste heat recovery apparatus including an exhaust tube having a cylindrical outer shell configured to contain a flow of exhaust fluid; a first heat exchanger extending through a first region of the exhaust tube, the first heat exchanger in thermal communication with the cylindrical outer shell; a second region of the exhaust tube extending through the exhaust tube, the second region having a low exhaust fluid pressure drop; an exhaust valve operatively disposed within the second region and configured to allow exhaust fluid to flow through the second region only when a flow rate of the exhaust fluid becomes great enough to result in back pressure beyond an allowable limit; and a plurality of thermoelectric elements in thermal communication with an outer surface of the outer shell.

Abstract: Applicants have discovered new composite materials and have developed a variety of new ways of making reactive composite materials (RCMs) and methods of controlling the properties and characteristics of the materials that are pertinent to numerous new or improved applications. This patent application is directed to new and improved ways of making reactive composite materials using mechanical deformation and making such materials with controlled, predictable characteristics. This application is also directed toward useful applications of the resulting materials. In accordance with the invention, RCMs are fabricated by a series of mechanical deformation steps. In the first deformation step, an assembly of reactive layers and/or particles is plastically deformed to reduce its cross sectional area by one-half or more. This severe initial deformation substantially eliminates the tendency of deformed layers to delaminate and eliminates the necessity of using specially cleaned metal layers.

Abstract: In accordance with the invention, containers or interfaces having two surfaces 201a and 201b to be joined, and a region to be sealed, are fused by providing between the surfaces 201a and 201b a thin strip or wire of RCM 102 embedded within a fusible material 101, applying pressure 205 and igniting the RCM 102. The released energy from the ignited RCM 102 results in a melting of the fusible material 101 and subsequent bonding of the fusible material 101 upon cooling to the 101 surrounding surfaces 201a and 201b, achieving a hermetic seal there between without the use of a separate gasket component.

Abstract: A method for bonding a concentrating photovoltaic receiver module to a heat sink using a reactive multilayer foil as a local heat source, together with layers of solder, to provide a high thermal conductivity interface with long term reliability and ease of assembly.

Abstract: Novel reactive composite materials and associated methods for making the same which are pertinent to numerous new or improved applications. The method for making the reactive composite materials utilizes mechanical deformation to manufacture such materials with controlled, predictable characteristics. In the first deformation step, an assembly of reactive layers and/or particles is plastically deformed to reduce its cross sectional area by one-half or more. Portions of the deformed sheets are stacked or bent into a new assembly, and the new assembly is then deformed. The steps of assembly and deformation are repeated a sufficient number of times that the resulting materials are only locally layered but have relatively uniform reaction velocity and heat generating characteristics predictable by stochastic models derived herein.

Abstract: The invention includes a method of joining two components. The method includes providing at least two components to be joined, a reactive multilayer foil, and a compliant element, placing the reactive multilayer foil between the at least two components, applying pressure on the two components in contact with the reactive multilayer foil via a compliant element, and initiating a chemical transformation of the reactive multilayer foil so as to physically join the at least two components. The invention also includes two components joined using the aforementioned method.

Abstract: 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 lawyers, 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.

Abstract: The invention includes a method of joining two components. The method includes providing at least two components to be joined, a reactive multilayer foil, and a compliant element, placing the reactive multilayer foil between the at least two components, applying pressure on the two components in contact with the reactive multilayer foil via a compliant element, and initiating a chemical transformation of the reactive multilayer foil so as to physically join the at least two components. The invention also includes two components joined using the aforementioned method.

Abstract: A reactive composite structure having selected energetic and mechanical properties, and methods of making reactive composite structures enabling the construction of complex parts and components by machining and forming of reactive composite materials without compromising the energetic or mechanical properties of the resulting reactive composite structure.

Abstract: The present inventors have observed that in some applications of reactive composite joining there is escape of a portion of the molten joining material through the edges of the joining regions. Such escape is not only a waste of expensive material (e.g. gold or indium) but also a reduction from the optimal thickness of the joining regions. In some applications, such escape also presents risk of short circuits or even fire. In this invention, two approaches are taken toward preventing damage to surroundings by the escape of molten joining material. First, escape may be prevented by trapping or containing the molten material near the joint, using barriers, dams, or similar means. Second, escape may be reduced by adjusting parameters within the joint, such as solder composition, joining pressure, or RCM thickness.

Abstract: 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.