Sensorelement zur Bestimmung von Dehnungen

WO15104015A2 [EN] The invention relates to a sensor element for determining expansions, in which a sensing element is secured to a surface of a component or substrate, and/or held clamped in at least two positions that are spaced apart from one another. Said sensing element is formed from an elastically-deformable polymer in which electrically-conductive particles are embedded, the percolation threshold of a percentage of said particles exceeded. Moreover, at least two contact points are present or formed spaced apart from one another on the sensing element, and designed to connect to an electrical voltage source, such that any expansion that occurs at said sensing element can be determined by acquiring a correspondingly changing electrical voltage, electrical current and/or electrical resistance, using a measurement device

Für die Herstellung von Kohlenstofffasern einsetzbares Modul sowie ein Verfahren zur Herstellung von Kohlenstofffasern

The invention relates to a module which can be used for producing carbon fibres and to a method for producing carbon fibres. The module is formed with at least one element (8, 9) which can be heated by electrical resistance heating and is connected to an electrical power source. At least one fibre (3), in particular at least one precursor fibre, which is to be stabilised or pre-carbonised in the module, is brought into physical contact with a planar surface of the at least one element (8, 9) and moved in a forward axial direction along the surface of the at least one element (8, 9)

Dielektrischer Elastomeraktor und Verfahren zu seiner Herstellung

The invention relates to dielectric elastomer actuators (DEA) and a production method for such elastomer actuators. According to the invention, an elastically deformable dielectric polymer film (1) is enclosed on two opposite surfaces by two elastically deformable electrodes. The electrodes are formed from a polymer in which electrically conductive particles, particularly carbon nanotubes, are embedded in a proportion at which the percolation threshold is overcome. The electrodes are connected to the dielectric film by a material bond, whereby structuring having recesses (2) is formed on at least one of the surfaces of the dielectric film on which an electrode is formed

Modifikation eines additionsvernetzten Silicons – Kombination verschieden modifizierter Elastomerschichten zur Herstellung eines Polymeraktors

Polymeraktoren auf Basis von hochelastischen elektroaktiven Polymeren stellen derzeit ein interessantes und vielversprechendes Forschungsfeld dar. Es werden konventionelle Elastomeraktoren mit bspw. metallischen Elektroden sowie Polymeraktoren nach dem vollpolymeren Ansatz untersucht. Die vollpolymeren Aktoren bestehen aus ein und demselben Basispolymer, welches für die unterschiedlichen Anforderungen entsprechend modifiziert wird. Ziel ist es, die Nachteile der konventionellen Systeme mit Hilfe der vollpolymeren Aktoren zu eliminieren, die Eigenschaften deutlich zu verbessern und somit das Interesse der industriellen Anwender im Bereich der Aktorik, Sensorik und Energiegewinnung zu wecken

Vorrichtung und Verfahren zur Herstellung von Kohlenstofffasern oder von textilen Gebilden, die mit Kohlenstofffasern gebildet sind

The invention for producing carbon fibres or textile fabrics comprises a module with two nozzles guided one inside the other, having different internal diameters. A first nozzle is arranged inside the second nozzle and one of the nozzles is connected to a supply reservoir, in which a polymer is stored, and the other nozzle is connected to a supply reservoir, in which electrically conducting particles are held in a dispersion. The dispersion in which electrically conducting particles are held is supplied from the supply reservoir through the one nozzle and the polymer is supplied through the other nozzle from the second supply reservoir, so that a fibre is obtained which is formed with a core and a jacket on exit from the nozzles. The core is formed from the polymer and the jacket from electrically conducting particles, or vice versa. The fibres made in this way or a textile fabric are supplied to a thermal treatment in which carbonization is achieved

Vorrichtung und Verfahren zur Karbonisierung oder Graphitisierung von Kohlenstoff enthaltenden Fasern oder einem mit Kohlenstoff enthaltenden Fasern gebildeten textilen Gebilde

The invention relates to a device for the carbonization or graphitization of carbon-containing fibers, in which fibers are guided through a continuous furnace in which partial pre-carbonization takes place. At least one device which comprises a heating zone and through which the fibers are guided following the achieved partial pre-carbonization is arranged within the continuous furnace or immediately after the continuous furnace. The at least one heating zone is formed by at least one pair of rollers or at least one pair of heating elements which are in electrically conductive contact with fibers, electrical resistance heating of the fibers takes place as a result of the connection of a roller or a heating element to a pole of an electric voltage source and the connection of the respective other roller or the respective other heating element of the pair of rollers or pair of heating elements to the respective other pole of the electric voltage source, and the rollers of a pair of rollers or the heating elements of a pair of heating elements are arranged at a distance from one another, which results in a further carbonization of the fibers

Material platform for dielectric elastomer actuators - important properties of the investigated material and long-term stability characteristics of the actuator layers

This paper will show a conceptual new material platform for dielectric elastomer actuators (DEA). The working principle of DEAs is based to the displacement of a flexible insulating dielectric which is placed between two electrodes. If an electrical voltage is applied, an electrostatic pressure will be generated, which forces the elastic material to stretch. State of the art actuators exhibit non-flexible metallic or graphite electrodes. The difference in flexibility leads to material incompatibilities and reduces the durability and long-term stability of actuator assemblies. The new material platform consists of only one basic polymer for all layers. Ceramic fillers were used to obtain a higher permittivity of the dielectric layer. The electrode layer was modified with nanoscale fillers like Carbon Nanotubes (CNT) to reach the needed specific conductivity. The newly developed material and actuator platform showed outstanding results regarding displacement, durability and long-term stability. The durability and long-term stability were demonstrated successfully using several mechanical and electro-mechanical stress tests with up to millions of load cycles

Vorrichtung und ein Verfahren zur Herstellung graphitisierter Kohlenstofffasern oder mit diesen Kohlenstofffasern gebildeten textilen Gebilden

Vorrichtung zur Herstellung graphitisierter Kohlenstofffasern oder textilen Gebilden, bei der zwei Module direkt miteinander verbunden oder in einem gemeinsamen Gehäuse angeordnet sind und mindestens eine Präkursorfaser oder ein mit Präkursorfasern gebildetes textiles Gebilde an einer Seite in die Vorrichtung eingeführt wird und in einem in Vorschubbewegungsrichtung vorderen ersten Modul Kontaktelemente oder Walzen angeordnet sind, die mit der Faser oder dem textilen Gebilde in unmittelbarem Kontakt stehen und die Kontaktelemente an jeweils einen Pol einer elektrischen Spannungsquelle angeschlossen sind, so dass mit der/den Faser(n) oder dem textilen Gebilde, den Kontaktelementen und den Spannungsquellen jeweils ein elektrischer Stromkreis gebildet ist, und/oder das erste Modul als konventioneller Ofen oder als Mikrowellenplasmagenerator ausgebildet ist und in einem zweiten Modul mindestens ein an eine elektrische Wechselspannungsquelle angeschlossener Induktor angeordnet ist, der so angeordnet und ausgebildet ist, dass die Faser(n) oder das/die textilen Gebilde durch ihn hindurchführbar oder daran entlang bewegbar ist/sind

Full Polymer Dielectric Elastomeric Actuators (DEA) Functionalised with Carbon Nanotubes and High-K Ceramics

Dielectric elastomer actuators (DEA) are special devices which have a simple working and construction principle and outstanding actuation properties. The DEAs consist of a combination of different materials for the dielectric and electrode layers. The combination of these layers causes incompatibilities in their interconnections. Dramatic differences in the mechanical properties and bad adhesion of the layers are the principal causes for the reduction of the actuation displacement and strong reduction of lifetime. Common DEAs achieve actuation displacements of 2% and a durability of some million cycles. The following investigations represent a new approach to solving the problems of common systems. The investigated DEA consists of only one basic raw polymer, which was modified according to the required demands of each layer. The basic raw polymer was modified with single-walled carbon nanotubes or high-k ceramics, for example, lead magnesium niobate-lead titanate. The development of the full polymer DEA comprised the development of materials and technologies to realise a reproducible layer composition. It was proven that the full polymer actuator worked according to the theoretical rules. The investigated system achieved actuation displacements above 20% regarding thickness, outstanding interconnections at each layer without any failures, and durability above 3 million cycles without any indication of an impending malfunction