Dielectric and piezoelectric properties for 0.62Pb(Mg 1/3Nb 2/3)O 3–0.38PbTiO 3 single crystals

• Published in: Ceramics international Vol. 29; no. 2; pp. 145 - 150
• Main Authors: Cao, Hu, Fang, Bijun, Luo, Haosu, Sun, Yihai, Guo, Jingkun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2003
• Subjects: C. Dielectric properties; C. Piezoelectric properties; Lead magnesium niobate titanate; C. Piezoelectric properties; Lead magnesium niobate titanate; C. Dielectric properties
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/S0272-8842(02)00098-6

The dielectric and piezoelectric properties of 0.62Pb(Mg 1/3Nb 2/3)O 3–0.38PbTiO 3 single crystal (PMNT62/38) were investigated in this work. Power X-ray diffraction demonstrated PMNT62/38 had a tetragonal structure at room temperature. The Curie temperature was 187 °C on heating. The poled and as-grown dielectric constants ε r of [001] oriented PMNT62/38 at room temperature were ∼500 and ∼5000, respectively. The remanent polarization P r and coercive field E c for [001] oriented one were 34.2 μC/cm 2 and 8.25 kV/cm, respectively. The strain at 15 kV/cm and −15k V/cm were 0.078 and 0.125%, respectively. The piezoelectric constant d 33 was ∼350 pC/N. The electromechanical coupling coefficients; 0.89 of k 33, 0.61 of k t, 0.46 of k 31 and 0.45 of k 15 were calculated from measured resonance and anti-resonance frequencies by impedance resonance techniques. In single domain process it was found the re-oriented domains of [001] poled PMNT62/38 were instable, which caused it hard to align the spontaneous polarizations to create a single domain crystal.