| 摘要 |
An internal electrode 3 contains Ni as its main constituent, a piezoelectric ceramic layer includes a main constituent represented by the general formula {(1 - x) (K 1-a-b Na a Li b )(Nb 1-c Ta c )O 3 } - xM2M4O 3 }, and as accessory constituents, 2± mol of Na, (± + ²) mole of an M4' element, and ³ mol of Mn with respect to 100 mol of the main constituent, wherein ±, ² and ³ respectively satisfy 0.1 ‰¤ ± ‰¤ ², 1 ‰¤ ± + ² ‰¤ 10, and 0 ‰¤ ³ ‰¤ 10, provided that M2 is Ca, Ba, and/or Sr, the M4 element and the M4' element are Zr, Sn, and/or Hf, and x, a, b, and c respectively are 0 ‰¤ x ‰¤ 0.06, 0 ‰¤ a ‰¤ 0.9, 0 ‰¤ b ‰¤ 0.1, and 0 ‰¤ c ‰¤ 0.3. Thus, even in the case of using Ni for an internal electrode material and carrying out co-firing, a favorable piezoelectric property can be obtained without causing defective polarization. |
