Low‐Temperature Sintering and Piezoelectric Properties of CuO ‐Added KNbO 3 Ceramics

• Published in: Journal of the American Ceramic Society Vol. 97; no. 12; pp. 3897 - 3903
• Main Authors: Kim, Dae‐Hyeon, Joung, Mi‐Ri, Seo, In‐Tae, Hur, Joon, Kim, Jong‐Hyun, Kim, Bo‐Yun, Lee, Hwack‐Joo, Nahm, Sahn
• Format: Journal Article
• Language: English
• Published: 01-12-2014
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/jace.13225

Dielectric and piezoelectric properties of
CuO
‐added
KNbO
3
(
KN
) ceramics were investigated. The
CuO
reacted with the
Nb
2
O
5
, formed a
CuO
–
Nb
2
O
5
‐related liquid phase during the sintering, and assisted the densification of the
KN
ceramics at low temperatures. Moreover, some of the
Cu
2+
ions replaced the
Nb
5+
ions in the matrix and behaved as a hardener. The dielectric and piezoelectric properties of the
KN
ceramics were considerably influenced by the relative density. The 1.0 mol%
CuO
‐added
KN
ceramic sintered at 960°C for 1.0 h, which showed a maximum relative density, exhibited a high phase angle of 86.9°,
P
r
of 14.8 μC/cm
2
, and
E
c
of 1.8 kV/mm. This specimen also exhibited good dielectric and piezoelectric properties: ε
T
33
/
ε
o
of 364,
d
33
of 122 pC/N,
k
p
of 0.29, and
Q
m
of 611.