Abstract: A method for heating a fiber/plastic composite material (FPC) comprising at least one layer (L) of carbon fibers (F) in a plastic matrix (P) includes inducing a magnetic field (MF) by means of a microwave antenna (MA) in the fiber/plastic composite material (FPC), and the field direction of the magnetic field (MF) runs in a plane of the layer (L) of carbon fibers (F).

Abstract: Method for heating a fiber/plastic composite material comprising at least one layer of carbon fibers in a plastic matrix, wherein a magnetic field is induced by means of a microwave antenna, and the field direction of the magnetic field runs in the plane of the layer of carbon fibers.

Abstract: A method for stabilizing yarns made from polyacrylonitrile using chemical stabilization reactions, including: generating a field of high-frequency electromagnetic waves in an application space of an applicator, which has areas with minimum electric field strength and areas with maximum electric field strength, the maximum electric field strength in the application space being in a range from 3 to 150 kV/m; continuously supplying a precursor yarn based on a polyacrylonitrile polymer into the application space, and conveying the precursor yarn through the application space and through the field of the high-frequency electromagnetic waves; introducing a process gas into the application space and conveying the process gas through the application space with a flow rate of at least 0.1 m/s relative to the precursor yarn being conveyed through the application space, wherein a temperature of the process gas is in a range between 150 and 300° C.

Abstract: A process for the production of hollow carbon fibres by the treatment of a stabilised carbon fibre precursor in an application device using high-frequency electromagnetic waves. The application device includes structure supplying the electromagnetic waves to a outcoupling region and a hollow outer conductor terminating in the outcoupling region. For the treatment, a field of the high-frequency electromagnetic waves is generated and a field strength in the range from 15 to 40 kV/m is set in the outcoupling region of the application device. The stabilised carbon fibre precursor is conveyed continuously as an inner conductor through the hollow outer conductor, thereby forming a coaxial conductor having an outer and an inner conductor, and through the subsequent outcoupling region. An inert gas atmosphere is created in the coaxial conductor and in the outcoupling region by passing through an inert gas.

Abstract: A process for continuous production of carbon fibres whereby stabilised precursor fibres are carbonised and graphitised with the help of high-frequency electromagnetic waves, characterised in that the stabilised precursor fibres are continuously conveyed, as the inner conductor of a coaxial conductor consisting of an outer and an inner conductor, through the coaxial conductor and a treatment zone; that the stabilised precursor fibres are irradiated in the treatment zone with high-frequency electromagnetic waves that are absorbed by the precursor fibres, which are thereby heated and converted into carbon fibres; and that the stabilised precursor fibres or carbon fibres are conveyed under an inert gas atmosphere through the coaxial conductor and the treatment zone.

Abstract: The aim of the invention is to provide an alternative to the intensive treatment of a product, especially plasma treatment, in specific areas only. Towards this end, the invention provides a device for producing microwaves for treating workpieces, comprising at least one microwave antenna with an extended conductor for producing alternating electromagnetic fields, a housing that substantially extends over the length of the conductor, and an extended microwave decoupling area which follows the conductor and which is located in the housing. The housing is formed by at least one resonant cavity, which has a long shape and follows the course of the microwave antenna. The resonant cavity has at least one tapering, closed, first crown area and the decoupling area essentially extends in the focussing area of the resonant cavity. An at least non-divergent housing area adjoins the resonant cavity.

Abstract: A propellant device of consisting of a compact charge and a firing system for pipe weapons or ballistic drives is proposed. At least one electromagnetic radiation absorbing medium, e.g. carbon black, is dispersed in the compact charge and can be activated by means of a firing system emitting electromagnetic radiation. The compact charge is thereby disintergrated in fragments through triggering of the firing system and the fragments are accelerated into the gas volume produced during burning of the compact charge. The inventive propellant device avoids the use of chemical firing as well as mechanical firing means. Moreover, fragmentation of the compact charge permits maintenance of the produced maximum pressure over a longer period of time to impart a higher muzzle velocity to an object to be accelerated, e.g. a projectile, a rocket or the like.

Abstract: Device for heating components 8, 8′ of a microwave-absorbing plastic material, said device incorporating a microwave generator 1 which generates microwaves of a particular frequency, an antenna 4 with at least one free end 5, 5′ to which the microwaves are conducted, and an enclosure 6 surrounding and shielding the antenna 4, with a heating zone 9, 9′ provided between the free end 5, 5′ of the antenna 4 and the shielding enclosure 6 for the localized heating of the components 8, 8′, said device featuring in the area of the heating zone 9, 9′ at least one temperature sensor 11, 11′ which is interactively unaffected by the microwaves and which is capable of determining the temperature of the component 8, 8′ during the heating process. This device in combination with the associated process for heating components 8, 8′ permits the monitoring of the temperature in the heating zone 9, 9′, thus ensuring a consistent quality level of the heated components.

Abstract: With a device for heating parts 8 made of a microwave absorbing plastic and having a microwave generator 1 that generates microwaves of a certain wavelength, an antenna 4 to which the microwaves are conducted, having at least one free end 5 and a device 6 which surrounds the antenna 4, it is proposed that the device for shielding 6 be designed with a tubular shape, so that the device 6 has an inside diameter smaller than half the wavelength, projects beyond the free end 5 of the antenna and has an opening 7 in its end face. With this device it is possible to achieve a spatially limited and nevertheless homogeneous heating of parts 8. Furthermore a method of heating or welding, shaping or crosslinking parts made of a microwave absorbing plastic using this device is also proposed.

Abstract: In order to manufacture compound composite bodies having at least two lay with a support material made completely or substantially from a polymer and with a porous layer firmly connected thereto, a substantially microwave-permeable polymer is utilized for the support material and a polymer having microwave absorbing properties is utilized for the porous layer. The polymer for the porous layer, treated with foaming agent, is heated with microwave energy up to the decomposition temperature of the foaming agent. The resulting polymer foam is sufficiently heated using microwave energy that the support material, at its bordering layer adjacent the foamed polymer, is sufficiently melted substantially due to heat conduction out of the foamed layer that, subsequent to cooling, a firm composite between the support material and the foamed polymer is effected.

Abstract: In order to enlarge the surface of particles which absorb liquids at least o a limited extent, the particles are exposed to a liquid or to a humid atmosphere containing this liquid at least until said liquid has penetrated into the area of the particles close to their surface, and the liquid-containing particles are then irradiated with micro-waves until the penetrated liquid evaporates. The surface of the particles is torn down to the depth of penetration of the liquid and thus enlarged, or the particles break up, creating small broken pieces with an irregular and enlarged surface.