摘要:
Systems and processes that integrate thermoplastic and shape memory alloy materials to form an adaptive composite structure capable of changing its shape. For example, the adaptive composite structure may be designed to serve as a multifunctional adaptive wing flight control surface. Other applications for such adaptive composite structures include in variable area fan nozzles, winglets, fairings, elevators, rudders, or other aircraft components having an aerodynamic surface whose shape is preferably controllable. The material systems can be integrated by means of overbraiding (interwoven) with tows of both thermoplastic and shape memory alloy materials or separate layers of each material can be consolidated (e.g., using induction heating) to make a flight control surface that does not require separate actuation.
摘要:
The invention relates to a measuring tape (10) comprising a stack of at least two layers, characterized in that it also includes a first layer, called support layer, based on composite material (11) and a layer, called top layer, (12) based on a polymer having a high glass transition temperature so that, in conditions of use, said polymer is in a glassy state to maintain the element in the wound or folded position.The invention also relates to a deployable structure including said measuring tape intended notably for space applications.
摘要:
In a heat-shrinkable tube (1) having a tubular member which is shrinkable in response to heat and has a cylindrical surface, a thin film is formed on at least a part of the cylindrical surface. The thin film is made of a magnetic loss material which has a high magnetic loss characteristic. The thin film has a first phase comprising a first one of Fe, Co, and Ni and has a second phase comprising an insulator containing at least one element other than Fe, Co, and Ni.
摘要:
A conductive polymer wraparound sleeve is used to enclose a joint between district heating pipes. It is wrapped so that longitudinal edges thereof overlap, and it acts as a source of heat to seal the overlapping longitudinal edges. Elongate electrodes, preferably metal bars provided on a carrying strip, are positioned along the overlap and connected to a power source to cause electrical current to flow circumferentially across the overlap region to cause bonding of the overlap.
摘要:
A coupler 10 consists of a length of cross-linked polyethylene pipe having a spiral groove 16 cut in its outer surface and another spiral groove cut in its inner surface. A heating element 18 is wound in the groove. The coupler is expanded mechanically so as to have an easy fit over the ends of polyethylene pipes 12, 14. The heater element 18 is energized and the coupler shrinks and forms fusion welded joints between itself and the pipes. No preparation of the pipe ends is necessary because the serrated inner surface cuts through the oxidized skin and bonds to material beneath the skin. The coupler is especially advantageous in large sizes of 500 mm or above. Instead of an electric heater, radiant energy, e.g. infra red or light is used to heat the coupler. For example, an array of reflector lamps can be used circumferentially located around the coupler.
摘要:
This invention relates to heat-recoverable devices that are self-heating and auto-regulating. The heat-recoverable articles of this invention comprise the combination of a heat-recoverable material and lossy heating particles, such as ferromanetic or ferrimagnetic particles, which produce heat when subjected to an alternating magnetic field and have a Curie temperature at or above the recovery temperature of the material and preferably below the decomposition temperature of the material. The particles can be in an electrically non-conductive layer, on or in thermal contact with the heat-recoverable material or can be dispersed in the heat-recoverable material. The system of this invention includes the heat-recoverable device or article, an induction coil for producing the magnetic field and an alternating current power supply for the induction coil. Preferably the power supply is high frequency and constant current, which produces efficient heating and preferred auto-regulating properties. Preferred particles are small particle size ferrites.
摘要:
A heat recoverable conductive polymeric tubular article shrinks radially when electrical current is passed therethrough. It is powered by elongate electrodes extending along the article along part of the length only of the article, thereby defining an inwardly directed electrode end material of the article preferably has specific electrical properties to compensate for the increased current density that would otherwise exist at the inwardly directed electrode end, and which could lead to burning or hot spot formation.
摘要:
A coupler for joining polymeric pipes comprises a generally cylindrical radially heat-shrinkable member which is composed of a conductive polymer. To recover the coupler, current is passed axially through the coupler via electrodes. The coupler has a center portion of increased wall thickness and in this way, when there is a gap between the pipes, overheating of the center portion of the coupler is avoided.
摘要:
An assembly which comprises a heat-recoverable article which is adapted to join substrates together and a plug which is in a recess of the article. The plug comprises a first polymer, e.g. nylon, which is opaque at room temperature and transparent at an elevated temperature, and preferably comprises a colored portion beneath the first polymer. When the article is connected to a power supply, it heats and recovers. At the recovery temperature of the substrate, the nylon melts and the colored portion becomes visible, thus indicating to an operator that the article should be disconnected from the power supply.
摘要:
An aperture, for example a duct having a cable passing through it, is sealed by installing a laminate, comprising an adhesive layer, a heater layer, and a heat-recoverable foam layer, the thickness of which increases on heating, into the gap between the duct wall and the cable with the adhesive layer facing both the wall and the cable. On energizing the heater, the foam increases in thickness and forces the adhesive into sealing engagement with the wall and cable.