| 摘要 |
The invention provides a piezoelectric ceramic material comprising a Bi3TiNbO9 crystal and/or an MBi2Nb2O9 crystal which are each a bismuth layer compound, where M represents at least one element selected from Sr, Ba and Ca. The ceramic material contains Bi, Ti, M and Nb as main component elements. The molar ratio as oxides of the main component elements is given by (Bi3-xMx)z (Nb1+yTi1-y)O9 provided that 0<x, y<=0.8 and 0.95<=z<=1.05. When the molar ratio of Ba/(M+Bi) is given by xB/3 and the molar ratio of Ca/(M+Bi) is given by xC/3, it is required that 0<=XB<=0.5 AND 0&LE;XC<0.4. This piezoelectric ceramic material, free from any lead whatsoever, has a sufficiently high Curie point, and exhibits ever more improved piezoelectric properties.
|
