PIEZOCERAMIC COMPOSITION, PIEZOCERAMIC BODY COMPRISING SAID COMPOSITION AND A METHOD FOR PRODUCING

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The invention relates to a piezoceramic composition with the general empirical formula Pb1-aREbZrxTiyTRzO3, in which RE represents a rare-earth element, selected from a group comprising europium, gadolinium, lanthanum, neodymium, praseodymium, promethium and/or samarium, with a rare-earth element fraction b, TR represents at least one transition metal, selected from the group comprising chromium, iron and/or manganese, with a transition metal valency WTR and a transition metal fraction z and whereby the following interrelation is valid : z > b/(4 - WTR). Homogenous PZT crystals with a maximum particle size are obtained even at low sintering temperatures by a non-stoichiometric dosing ratio of transition metal dosage to rare-earth element dosage. By varying the dosages, the piezoelectric characteristics of a PZT ceramic with said composition can be modified from those of a classic soft PZT to those of a classic hard PZT. The piezoceramic body is for example a monolithic, multi-layer piezoactuator, which can be used for multiple injections in the engine of a motor vehicle, as a result of a high d33 coefficient and low internal dissipation in the high-level signal range.