Piezoelectric properties of nonstoichiometric Sr{sub 1-x}Bi{sub 2+2x/3}Ta{sub 2}O{sub 9} ceramics

Journal Article · Wed Jun 15 00:00:00 EDT 2005 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1903105· OSTI ID:20711764

Jain, Rajni; Chauhan, Arun Kumar Singh; Gupta, Vinay; Sreenivas, K ^[1]

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1. Department of Physics and Astrophysics, University of Delhi, Delhi-110007 (India)

The effect of poling on the structural, dielectric, and piezoelectric properties has been investigated for sol-gel-derived strontium bismuth tantalate (SBT) [Sr{sub 1-x}Bi{sub 2+2x/3}Ta{sub 2}O{sub 9}] ceramics with x=0.0,0.15,0.30,0.45. The dielectric and ferroelectric properties are found to improve with increase in x up to 0.3. Beyond x>0.3 the properties are found to degrade due to the limited solid solubility and the presence of a mixed phase of bismuth tantalate (BiTaO{sub 4}) is detected with x=0.45. Poling treatment reduces the dielectric dispersion and dielectric loss in the frequency range (0.1-100 kHz). The resonance and antiresonance frequencies increase with increase in x (x=0-0.30), and the corresponding minimum impedance decreases. The measured coupling coefficients (k{sub p}) are small (0.0967-0.1) for x=0-0.30, and the electromechanical quality factor (Q{sub m}=915) is a maximum for the Sr{sub 0.7}Bi{sub 2.2}Ta{sub 2}O{sub 9} composition (x=0.30). The estimated piezoelectric charge coefficient (d{sub 31}) and piezoelectric voltage coefficient (g{sub 31}) are 5.2 pC/N and 5.8x10{sup -3} V m/N, respectively. The positive values of d{sub 31} and g{sub 31} and the low dielectric permittivity of SBT yield a high value for the hydrostatic coefficients, despite the low charge coefficient of d{sub 33}=24 pC/N. The maximum values of charge coefficient (d{sub h}=34 pC/N) and voltage coefficient (g{sub h}=39x10{sup -3} V m/N) are obtained for Sr{sub 0.7}Bi{sub 2.2}Ta{sub 2}O{sub 9} composition, and the estimated hydrostatic figure of merit (d{sub h}g{sub h}x10{sup -15}=1215 m{sup 2}/N) is high.

• OSTI ID: 20711764
• Journal Information: Journal of Applied Physics, Vol. 97, Issue 12; Other Information: DOI: 10.1063/1.1903105; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BISMUTH COMPOUNDS
CERAMICS
DIELECTRIC MATERIALS
DISPERSIONS
ELECTRIC IMPEDANCE
ELECTRIC POTENTIAL
HZ RANGE
KHZ RANGE 01-100
PERFORMANCE
PERMITTIVITY
PIEZOELECTRICITY
POLARIZATION
QUALITY FACTOR
RESONANCE
SOL-GEL PROCESS
SOLUBILITY
STOICHIOMETRY
STRONTIUM COMPOUNDS
TANTALATES