Journal of the American Ceramic Society, Vol.97, No.7, 2076-2081, 2014
Structure Evolution and Electrical Properties of Y3+-Doped Ba1-xCaxZr0.07Ti0.93O3 Ceramics
Lead free piezoelectric ceramics of Y3+-doped Ba1-xCaxZr0.07Ti0.93O3 with x = 0.05, 0.10, and 0.15 were prepared. Composition and temperature-dependent structural phase evolution and electrical properties of as-prepared ceramics were studied systematically by X-ray diffraction, Raman spectroscopy, impedance analyzer, ferroelectric test system, and unipolar strain measurement. Composition with x = 0.10 performs a good piezoelectric constant d(33) of 363 pC/N, coercive field E-c of 257 V/mm, remanent polarization Pr of 14.5 mu C/cm(2), and a Curie temperature T-m of 109 degrees C. High-resolution X-ray diffraction was introduced to indicate presence of orthorhombic phase. Converse piezoelectric constant d(33)* of x = 0.10 composition performed better temperature stability in the range from 50 degrees C to 110 degrees C. That means decreasing orthorhombic-tetragonal phase transition temperature could be an effective way to enlarge its operating temperature range.