Patent Application
20150194241
The field of the present disclosure relates generally to electrical conductors, and more specifically, to electrical conductors formed at least partially from graphite intercalation compounds.
In at least some known applications, electrical power, current, and electrical/electronic signals are typically conducted through wires or cables. Generally, known electrical wires or cables include a conductor core and an insulative jacket disposed peripherally about the conductor core. At least some known conductor cores are fabricated from materials such as copper, silver, gold, and aluminum. While these known materials have desirable electrical conductivity, it is a continuing goal to reduce weight in many known applications by developing electrical conductors having reduced weight and at least comparable electrical conductivity to known metallic electrical conductors. For example, in the aerospace industry, reducing the weight of an aircraft typically results in increased fuel efficiency, and/or increased payload capacity.
At least one known attempt at developing electrical conductors having reduced weight and comparable electrical conductivity has included forming electrically conductive graphite intercalation compounds. Intercalation is the process of introducing guest molecules or atoms between graphene layers of graphitic carbon. More specifically, at least some known processes effectively introduce “dopant” guest molecules or atoms between the graphene layers via diffusion due to the relatively weak bond strength between adjacent graphene layers in graphitic carbon. While graphite intercalation compounds have desirable electrical conductivity and reduced weight when compared to metallic electrical conductors of similar size, graphite intercalation compounds are generally brittle and susceptible to exfoliation of the graphene layers when exposed to increased temperatures. Moreover, intercalating graphitic carbon with guest molecules or atoms generally only increases the in-plane electrical conductivity of the graphitic carbon, and reduces the electrical conductivity of the graphitic carbon normal to the planes.
In one aspect of the disclosure, an electrical conductor is provided. The electrical conductor includes a graphite intercalation compound and at least one layer of electrically conductive material extending over at least a portion of the graphite intercalation compound. The graphite intercalation compound includes a carbon-based particle and a plurality of guest molecules intercalated in the carbon-based particle.
In another aspect of the disclosure, an electrical conductor is provided. The electrical conductor includes a base matrix of electrically conductive material and a plurality of graphite intercalation compounds dispersed in the base matrix. Each of the plurality of graphite intercalation compounds include a carbon-based particle and a plurality of guest molecules intercalated in the carbon-based particle.
In yet another aspect of the disclosure, a method of forming an electrical conductor is provided. The method includes providing a graphite intercalation compound that includes a carbon-based particle and a plurality of guest molecules intercalated in the carbon-based particle. The method also includes extending electrically conductive material over at least a portion of the graphite intercalation compound. The electrically conductive material is in the form of at least one layer of electrically conductive material or a base matrix of electrically conductive material.
The implementations described herein relate to electrical conductors formed at least partially from graphite intercalation compounds (GICs). GICs are formed from carbon-based particles having a plurality of guest molecules intercalated therein. In the exemplary implementation, the GIC is then surrounded by an electrically conductive material to form the electrical conductors described herein. For example, the electrically conductive material may be in the form of either at least one layer or a base matrix of electrically conductive material. GICs can have about five times greater in-plane electrical conductivity and weigh about four times less than metallic electrical conductors of similar size, such as copper. As such, the electrical conductors described herein weigh less and have at least comparable electrical conductivity relative to similarly sized electrical conductors formed from known metallic, electrically conductive material.
Referring to the drawings, implementations of the disclosure may be described in the context of an aircraft manufacturing and service method 100 (shown in
Each portion and process associated with aircraft manufacturing and/or service 100 may be performed or completed by a system integrator, a third party, and/or an operator (e.g., a customer). For the purposes of this description, a system integrator may include without limitation any number of aircraft manufacturers and major-system subcontractors; a third party may include without limitation any number of venders, subcontractors, and suppliers; and an operator may be an airline, leasing company, military entity, service organization, and so on.
As shown in
Apparatus and methods embodied herein may be employed during any one or more of the stages of method 100. For example, components or subassemblies corresponding to component production process 108 may be fabricated or manufactured in a manner similar to components or subassemblies produced while aircraft 102 is in service. Also, one or more apparatus implementations, method implementations, or a combination thereof may be utilized during the production stages 108 and 110, for example, by substantially expediting assembly of, and/or reducing the cost of assembly of aircraft 102. Similarly, one or more of apparatus implementations, method implementations, or a combination thereof may be utilized while aircraft 102 is being serviced or maintained, for example, during scheduled maintenance and service 116.
As used herein, the term “aircraft” may include, but is not limited to only including, airplanes, unmanned aerial vehicles (UAVs), gliders, helicopters, and/or any other object that travels through airspace. Further, in an alternative implementation, the aircraft manufacturing and service method described herein may be used in any manufacturing and/or service operation.
As described above, guest molecules 208 are intercalated in carbon-based particle 206. More specifically, guest molecules 208 are positioned between adjacent layers 212 of graphene of carbon-based particle 206. Guest molecules 208 are fabricated from any material that enables electrical conductor 200 to function as described herein. Exemplary materials include, but are not limited to, bromine, calcium, and potassium.
In the exemplary implementation, layers 204 of electrically conductive material include a first layer 214 of electrically conductive material, a second layer 216 of electrically conductive material, and a third layer 218 of electrically conductive material. First layer 214 extends over at least a portion of GIC 202, second layer 216 extends over at least a portion of first layer 214, and third layer 218 extends over at least a portion of second layer 216. Each of first, second, and third layers 214, 216, and 218 serve a different function. For example, in the exemplary implementation, first layer 214 facilitates adhering second layer 216 to GIC 202, second layer 216 is fabricated from electrically conductive material that may be less expensive than material used to form first and third layers 214 and 218, and third layer 218 facilitates protecting second layer 216 from oxidation and/or physical strain, for example. In an alternative implementation, electrical conductor 200 may include any number of layers 204 that enable electrical conductor 200 to function as described herein.
Each layer 204 may be fabricated from any material that enables electrical conductor 200 to function as described herein. In the exemplary implementation, each layer 204 is fabricated from different materials. Exemplary materials used to fabricate first layer 214 include, but are not limited to, chromium and titanium. Exemplary materials used to fabricate second layer 216 include, but are not limited to, copper, silver, gold, and aluminum. Exemplary materials used to fabricate third layer 218 include, but are not limited to, silver, gold, and aluminum. Layers 204 are applied over GIC 202 via any suitable process. Exemplary processes include, but are not limited to, sputtering, ion beam plating, electroplating, electroless plating, wet chemical, and vapor deposition.
In the exemplary implementation, layers 204 extend over GIC 202 such that guest molecules 208 are fully enclosed within carbon-based particle 206. More specifically, layers 204 extend over GIC 202 in both planar direction 210 and a normal direction 220 relative to planar direction 210 to encapsulate GIC 202 in an electrically conductive overlayer (not shown). In some implementations, extending layers 204 over GIC 202 in normal direction 220 facilitates increasing the electrical conductivity of electrical conductor 200 in normal direction 220. As described above, intercalating guest molecules 208 in carbon-based particle 206 generally only increases the electrical conductivity of GIC 202 in planar direction 210. More specifically, intercalating guest molecules 208 in carbon-based particle 206 increases a distance D between adjacent graphene layers 212. The electrical conductivity of carbon-based particle 206 in normal direction 220 is reduced as distance D increases. As such, in the exemplary implementation, layers 204 provide a low-resistance interconnection path between the high in-plane conductivity of a given GIC 202 to multiple GICs 202 to form an electrically conductive composite layer (not shown).
In some implementations, multiple electrical conductors 200 may be interconnected to facilitate forming an elongated electrical conductor (not shown). For example, multiple electrical conductors 200 may be physically, chemically, and/or electrochemically joined to facilitate forming the elongated electrical conductor. Because layers 204 are formed from electrically conductive material, interconnecting multiple electrical conductors 200 facilitates forming a substantially continuous electrical conductor.
Because GICs 202 generally have a lower weight comparable or greater electrical conductivity than the material used to fabricate base matrix 226, dispersing GICs 202 in base matrix 226 forms electrical conductor 224 that weighs less than a similarly sized conventional electrical conductor formed only from the base matrix material. As such, the weight reduction is a function of a volume percentage of GICs 202 in electrical conductor 224. Any volume percentage of GICs 202 in electrical conductor 224 may be selected that enables electrical conductor 224 to function as described herein. In the exemplary implementation, the volume percentage of GICs 202 in electrical conductor 224 is up to about 70 percent of electrical conductor 224 by volume, which may result in at least about a 50 percent weight reduction of electrical conductor 224 when compared to conventional electrical conductors, such as copper.
The implementations described herein include electrical conductors having reduced weight and at least comparable electrical conductivity relative to purely metallic electrical conductors of similar size. More specifically, the electrical conductors described herein are at least partially formed from graphite intercalation compounds. As described above, graphite intercalation compounds can have about five times greater electrical conductivity and weigh about four times less than purely metallic electrical conductors, such as copper conductors. As such, the electrical conductors described herein weigh less and have at least comparable electrical conductivity relative to similarly sized electrical conductors formed from known metallic, electrically conductive material.
This written description uses examples to disclose various implementations, including the best mode, and also to enable any person skilled in the art to practice the various implementations, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
