Premium
Effect of the Addition of CaZrO 3 and LiNbO 3 on the Phase Transitions and Piezoelectric Properties of K 0.5 Na 0.5 NbO 3 Lead‐Free Ceramics
Author(s) -
Liang Wenfeng,
Wu Wenjuan,
Xiao Dingquan,
Zhu Jianguo
Publication year - 2011
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2011.04660.x
Subject(s) - materials science , piezoelectricity , orthorhombic crystal system , phase transition , ceramic , ferroelectricity , tetragonal crystal system , dielectric , phase (matter) , atmospheric temperature range , mineralogy , analytical chemistry (journal) , condensed matter physics , crystal structure , crystallography , composite material , optoelectronics , thermodynamics , chemistry , physics , organic chemistry , chromatography
The (1‐ x ‐ y )K 0.5 Na 0.5 NbO 3 ‐ x CaZrO 3 ‐ y LiNbO 3 (KNLNCZ‐ x ‐ y ) lead‐free piezoelectric ceramics were fabricated by conventional technique, and the effect of the addition of CaZrO 3 and LiNbO 3 on the phase transitions and piezoelectric properties of the KNN ‐based ceramics was investigated. The addition of CaZrO 3 will shift the orthorhombic‐rhombohedral transition temperature of the ceramics to above room temperature, and with the increase of the CaZrO 3 additives, a dielectric peak rises up near the orthorhombic‐tetragonal phase transition of the ceramics resulting in the spread of the ferroelectric‐paraelectric phase transition over a rather wide temperature range due to polar nanoregions arising from composition fluctuation. For x = 0.05, the addition of LiNbO 3 is effective to shift the T R‐O and T O‐T downward and T C upward in KNLNCZ‐0.05‐ y ceramics. Optimum piezoelectric properties ( d 33 = 216 pC/N and k p = 42.9%) were obtained for the KNLNCZ ‐ x ‐ y ceramics with x = 0.05 and y = 0.07 due to the decrease of T O‐T to be around room temperature.