Fiber reinforced thermoplastics offer substantial advantages over fiber reinforced thermosetts. Besides high specific stiffness and strength and excellent resistance to impact damage, especially with respect to the manufacturing process considerable cost reductions are possible'. The reason is the reduction of the processing times from hours to minutes. However the higher process temperatures close to the Curie temperature in the range from 2500 C to 400° C are expected to have a significant impact on the polarization of embedded piezocerarnic patches.Active structures require by definition embedded actuators and sensors as part of the load bearing structure. The success of the design philosophy of active structures is highly dependent on the manufacturing costs. For that reason fiber reinforced thermoplastics are supposed to be the ideal material for the host structure. Different manufacturing processes were applied to manufacture active test structures which are specifically designed with respect to the manufacturing process used. The embedding process of the active elements include the electrical insulation and wiring. Moreover the coefficient of thermal expansion (CII) of a typical PZT type ceramic was measured over a wide temperature range to understand the thermomechanical loading of the piezoceramic due to the manufacturing process.Moreover the electromechanical parameters of the active elements before and after the manufacturing process were measured. For this purpose a special test equipment has been developed. Furthermore the problem of thermal depolarization is touched.Basically it turns out that in spite of high processing temperatures the embedding of piezoceramics in fiber reinforced thermoplastics is feasible. The repolarization process of embedded piezoceramics is optimized for a given type of piezocerainics.

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