Piezoelectric ceramic, and piezoelectric, dielectric or pyroelectric element using the same

US8354038B2 · kind B2 · utility

Assignee

• National Institute of Advanced Industrial Science and Technology · JP

Inventors

• Ruiping Wang · Zhejiang, CN
• Hiroshi Bando · Tokyo, JP

Key dates

• Filing date: May 16, 2008
• Grant date: Jan 15, 2013
• Expiry date: May 16, 2028

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B2235/85
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A piezoelectric solid solution composition containing, as a main component, a composition represented by the following general formula:{Mx(NayLizK1-y-z)1-x}1-m{(Ti1-u-vZruHfv)x(Nb1-wTaw)1-x}O3 is disclosed. In the formula, M represents a combination of at least one member selected from the group consisting of (Bi0.5K0.5), (Bi0.5Na0.5) and (Bi0.5Li0.5) and at least one member selected from the group consisting of Ba, Sr, Ca and Mg; and in the formula, x, y, z, u, v, w and m are in the following ranges: 0.06<x≦0.3, 0≦y≦1, 0≦z≦0.3, 0≦(y+z)≦1, 0<u≦1, 0≦v≦0.75, 0≦w≦0.2, 0<(u+v)≦1 and −0.06≦m≦0.06. This solid solution composition preferably forms the same rhombohedral-tetragonal morphotropic phase boundary as in PZT, is environmentally friendly, and displays an excellent piezoelectric constant d33.