| 摘要 |
PROBLEM TO BE SOLVED: To provide a piezoelectric ceramic which contains no lead and has a sufficiently high Curie point and also shows excellent piezoelectric characteristics. SOLUTION: This piezoelectric ceramic comprises Bi3TiNbO9 type bismuth layer compound crystals and/or MBi2Nb2O9 (M is at least one element selected from Sr, Ba and Ca) type bismuth layer compound crystals, and also contains, as the main constituent elements, Bi, Ti, M and Nb, wherein the molar ratios (expressed in terms of oxides) of Bi, Ti, M and Nb to each other, are represented by the formula: (Bi3-xMx)z(Nb1+yTi1-y)O9 [0<x, y<=0.8, and 0.95<=z<=1.05], and when the molar ratios Ba/(M+Bi) and Ca/(M+Bi) are represented by xB/3 and xC/3 respectively, 0<=xB<=0.5 and 0<=xC<0.4. |
