| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a piezoelectric ceramic composition having larger relative permittivity εr, an electromechanical coupling factor K and vibration speed limit Vmax, in order to secure long service life and stable piezoelectric characteristics of a piezoelectric transformer. <P>SOLUTION: This piezoelectric ceramic composition is obtained by subjecting a composite perovskite being a ceramic composition for a piezoelectric transformer to solid solution treatment into a multicomponent PZT-based piezoelectric ceramic Pb(Mn<SB>1/3</SB>Sb<SB>2/3</SB>)O<SB>3</SB>-PbZrO<SB>3</SB>-PbTiO<SB>3</SB>as a third component, and Pb(Mn<SB>1/3</SB>Nb<SB>2/3</SB>)O<SB>3</SB>and Pb(Sb<SB>1/2</SB>Nb<SB>1/2</SB>)O<SB>3</SB>are added thereto as a fourth and a fifth main components, respectively. The piezoelectric ceramic composition is obtained by selecting each specific composition range to increase the relative permittivity εr and the electromechanical coupling factor K, and by defining the scope of composition capable of realizing the high vibration speed limit Vmax to realize ≥0.6 electromechanical coupling factor K33 at the axial vibration mode, ≥600 relative permittivity εr and ≥0.3 m/s vibration speed limit Vmax. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
