| 摘要 |
PURPOSE:To obtain a composition useful for giving piezoelectric ceramic elements having high heat resistance and electromechanical coupling coefficient with small variation in its physical properties for a long time. CONSTITUTION:A piezoelectric ceramic composition of general formula Pbalpha[Mg1/3Nb2/3)a(Yb1/2Nb1/2)bTicZrd]O3 [where, (a+b+c+d)=1]. This composition is designed to be the basic composition satisfying the following relationships: 0.95<=alpha<=-1.05, 0.01<=a<=0.15, 0.01<=b<=0.10, 0.30<=c<=0.60, and 0.25<=d<=0.55. Beside, this composition is incorporated, as subcomponent(s), with 0.01-3.0wt.% of at least one kind selected from Cr, Mn, Co and Ni in terms of Cr2O3, MnO2, CoO and NiO, respectively. |
