| 摘要 |
A piezoelectric ceramic includes a perovskite phase of empirical formula: Ap(Nb1wzTawSbz)3, where Ap = alkali metal of the perovskite phase and w = 0-0.15, and z = 0-0.15. It also includes a tungsten bronze phase, with an empirical formula: Aw5(Nb1-vTav)5O15, where Aw = at least one alkali metal of the tungsten bronze phase and v = 0-1. The empirical formulae are presented for particular implementations of the phases. The molar lead content of the piezoceramic composition is less than 0.1 mol.%; it is especially below 0.01 mol.%. To make the material, a green body is formed using proportions satisfying the empirical composition. It is heated to form the corresponding ceramic. The starting mixture includes powdered, oxidic metal compounds of the alkali metals Ap of the perovskite phase, alkali metals Aw of the tungsten bronze phase, and niobium. If appropriate tantalum and antimony are also present in the initial composition. A mixed oxide is used with at least two of the metals. The piezoceramic component (10) formed includes a piezoelectric section (13) sandwiched between two electrode layers (11, 12) of different materials. The electrode materials are selected from silver, copper and palladium. The piezoelectric component is a: flexural sensor or strain gauge, multi-layer actuator, piezoceramic transformer, piezoceramic motor or a piezoceramic ultrasonic transducer. An independent claim is included for the production of the above material. |
