| 摘要 |
PROBLEM TO BE SOLVED: To provide a piezoelectric ceramic and a piezoelectric actuator having great specific permittivities and d constants and capable of mitigating depolarizations arising in accordance with drives thereof.SOLUTION: The provided piezoelectric ceramic has a PZT-type perovskite structure, includes, as compositional elements, Pb, Sr, Mg, Nb, Zr, and Ti, has a specific permittivity of 3000 or above and a piezoelectric strain constant dof 200 or above, and yields, in a case where the impressed voltage retention time at room temperature is assumed to be 1 sec, an insulation resistance-minimizing impression reverse voltage of 670 V/mm or above. It accordingly becomes possible to mitigate depolarization arising in accordance with the impression of a reverse voltage against the polarizing direction while the specific permittivity and d constant are increased. |
