Patent number: 7691286
Abstract: A piezoelectric ceramic composition includes a primary component represented by the formula (1-x)(K1-a-bNaaLib)m(Nb1-c-dTacSbd)O3-xM1nM2O3, and 0.1 to 10 moles (preferably 1.5 to 10 moles) of at least one specific element selected from the group consisting of In, Sc, Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu with respect to 100 moles of the primary component, wherein M1 is Ca, Sr, or Ba M2 is Ti, Zr, or Sn; and x, a, b, c, d, m, and n satisfy 0.005?x?0.1, 0?a?0.9, 0?b?0.3, 0?a+b?0.9, 0?c?0.5, 0?d?0.1, 0.9?m?1.1, and 0.9?n?1.1. Preferably, Mn, Ni, Fe, Zn, Cu, or Mg is further added. As a result, at both a very low and a high electric field, a high piezoelectric d constant can be stably obtained with a high efficiency.
Type:
Grant
Filed:
September 10, 2007
Date of Patent:
April 6, 2010
Assignee:
Murata Manufacturing Co., Ltd.
Inventors:
Shinichiro Kawada, Ryoko Katayama, Katsuhiro Horikawa
Publication number: 20080290316
Abstract: A piezoelectric ceramic composition represented by the formula (1-x) (K1-a-bNaaLib)m(Nb1-c-dTacSbd)O3-x(K1/4Na1/4M31/2) M4O3, wherein M3 represents a metal element that is at least one of Yb, Y, In, Nd, Eu, Gd, Dy, Sm, Ho, Er, Tb, and Lu; M4 represents a metal element that is at least one of Ti, Zr, and Sn; and x, a, b, c, d, and m satisfy the inequalities 0.001?x?0.1, 0?a?0.9, 0?b?0.3, 0?a+b?0.9, 0?c?0.5, 0?d?0.1, and 0.7?m?1.3. The piezoelectric ceramic composition is not sintering resistant and has desired, sufficient piezoelectric properties as well as a sufficient firing temperature range suitable for mass production. Furthermore, the piezoelectric ceramic composition is effective in preventing insufficient polarization and effective in increasing the yield of products.
Type:
Application
Filed:
August 7, 2008
Publication date:
November 27, 2008
Applicant:
MURATA MANUFACTURING CO., LTD.
Inventors:
Ryoko Katayama, Shinichiro Kawada, Katsuhiro Horikawa
Publication number: 20080061263
Abstract: A piezoelectric ceramic composition includes a primary component represented by the formula (1-x)(K1-a-bNaaLib)m(Nb1-c-dTacSbd)O3-xM1nM2O3, and 0.1 to 10 moles (preferably 1.5 to 10 moles) of at least one specific element selected from the group consisting of In, Sc, Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu with respect to 100 moles of the primary component, wherein M1 is Ca, Sr, or Ba M2 is Ti, Zr, or Sn; and x, a, b, c, d, m, and n satisfy 0.005?x?0.1, 0?a?0.9, 0?b?0.3, 0?a+b?0.9, 0?c?0.5, 0?d?0.1, 0.9?m?1.1, and 0.9?n?1.1. Preferably, Mn, Ni, Fe, Zn, Cu, or Mg is further added. As a result, at both a very low and a high electric field, a high piezoelectric d constant can be stably obtained with a high efficiency.
Type:
Application
Filed:
September 10, 2007
Publication date:
March 13, 2008
Inventors:
Shinichiro Kawada, Ryoko Katayama, Katsuhiro Horikawa