The lead-free piezoceramic material with alkaline-earth doping, method for producing a piezoceramic

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The invention relates to a lead-free piezoceramic material, having at least one perovskite phase with the empirical formula Ap(Nb1-wTaw)O3, in which Ap represents at least one alkali metal of the perovskite phase and the following relationship applies : 0 = w = 0.15, and at least one tungsten bronze phase with the empirical formula AwEw2Nb5O15, where Aw represents at least one alkali metal of the tungsten bronze phase and Ew represents at least one alkaline earth metal of tungsten bronze. The invention also relates to a method for producing a piezoceramic component using the piezoceramic material, said method comprising the following steps : a) provision of a green body using a piezoceramic parent composition of the piezoceramic material and b) thermal treatment of the green body, the piezoceramic material of the component being produced from the piezoceramic parent composition. The thermal treatment comprises the calcination and/or sintering of the piezoceramic composition. The resultant piezoceramic material exhibits excellent piezoelectric characteristics, for example a d33 co-efficient of approximately 300 pm/V and a Curie temperature of 320° C. The piezoceramic component is for example an ultrasonic transducer or a piezo bimorph. In particular the piezoceramic component is a multi-layer piezo actuator, used to control a fuel valve of an internal combustion engine in a motor vehicle.