| 摘要 |
A piezoelectric ceramic composition by which it is possible to obtain piezoelectric ceramic chip parts having a high electromechanical coupling factor and a high heat-resistance property, and also having a good temperature coefficient of resonance frequency while maintaining the high heat-resistance property and low change over time. The piezoelectric ceramic compositions of the present invention include: (1) a first piezoelectric ceramic composition expressed by the general formula Pby[(Mg1/3Nb2/3)a(Yb1/2Nb1/2)bTicZrd]O3 (where a+b+c+d=1), wherein 0.95</=y</=1.05, 0.01</=a</=0.15, 0.01</=b</=0.10, 0.30</=c</=0.60, and 0.25</=d</=0.55; (2) a second piezoelectric ceramic composition expressed by the general formula (Pb1-xMex)[(Mg1/3Nb2/3)a(Yb1/2Nb1/2)b TicZrd]O3 (where Me represents at least one element selected from Ba, Sr and Ca, and a+b+c+d=1), wherein 0</=x</=0.12, 0.01</=a</=0.15, 0.01</=b</=0.10, 0.30</=c</=0.60, and 0.25</=d</=0.55; (3) a third piezoelectric ceramic composition in which Yb, treated as trivalent in the first piezoelectric ceramic composition, is treated as bivalent and which is expressed by the general formula Pb[(Mg1/3Nb2/3)e(Yb1/3Nb2/3)fTigZrh]O3 (where Me represents at least one element selected from Ba, Sr and Ca, and e+f+g+h=1), wherein 0<x</=0.12, 0.01</=e</=0.15, 0.01</=f</=0.15, 0.30</=g</=0.60, and 0.25</=h<0.58; (4) a fourth piezoelectric ceramic composition that is obtained by adding at least one element selected from Cr and Mn as a secondary component to the third piezoelectric ceramic composition, and (5) a fifth piezoelectric ceramic composition expressed by the general formula (Pb1-xMex)[(Mg1/3Nb2/3)e(Yb1/3Nb2/3)fTigZrh]O3 (where Me represents at least one element selected from Ba, Sr and Ca, and e+f+g+h=1), wherein 0<x</=0.12, 0.01</=e</=0.15, 0.01</=f</=0.15, 0.30</=g</=0.60, and 0.25</=h<0.58.
|
