The invention relates to a carrier for structural parts to be subjected to a heat-treatment process, comprising at least one frame and a lattice extending therefrom comprising intersecting strands, the frame consisting of one or more limbs, which preferably form a polygon, and the frame comprising temperature-resistant material and the strands, extending from the limb or pieces of the frame to form the lattice, comprising carbon fibers or ceramic fibers.
To position or fix slim metallic or ceramic structural parts and components during heat-treatment processes, they are inserted into holding frames. Heat-treatment processes are, for example, sintering processes, hardening processes, finishing processes or soldering processes. Usual processing temperatures are between 700° C. and 2600° C., whereby one typically works at between 800° C. and 1600° C.
According to the prior art, frames having such lattices comprise metal. The lattices are thereby formed by strands in the form of rods having e.g. a diameter of 2 mm. However, such holding devices exhibit considerable disadvantages which can be seen, inter alia, in the following:                distortions during thermal cycles,        creep of the entire structure due to the effect of temperature,        high dead weight,        high heat capacity,        short life due to embrittlement,        high cost of adjustment to extend useful life,        increased waste of the parts to be treated due to distortion of the holding device.        
Due, particularly, to a reduced shape stability, problems are often caused in loading or unloading such holding devices by means of manipulators such as robots.
A fibrous composite part having a lattice-like structure which is used in high-temperature furnaces and system construction, in heat-treating technology or sintering technology as a grate, is known from DE-A 199 57 906. A fiber preform, which is produced especially according to the TFP (Tailored Fiber Placement) technology and then pyrolyzed, i.e. carbonized or graphitized, is used for the production.
A carrier for hardening material is described in DE-U 295 12 569. In this case, the carrier comprises carbon fiber-reinforced carbon material (CFC material) which can have a protective layer consisting of SiC, BN or TiN. The carrier comprises limbs that can be interconnected and have recesses that are aligned to one another through which the material to be hardened is passed.
USPTO Backgrounds
USPTO Backgrounds