Composition-related structural, thermal and mechanical properties of Ba_1−xSr_xTiO₃ ceramics (0 ≤ x ≤ 0.4)

Abstract

The Ba_1−xSr_xTiO₃ (BST) ceramics were prepared by conventional ceramic method. The crystalline structure and morphology were studied by X-ray diffraction and scanning electron microscopy, respectively. Experimental results show that increase of sintering temperature leads to an uncontrolled precipitating of the phase with a lower content of Ti. The dielectric constant and specific heat as a function of composition and temperature were investigated. The increasing concentration of Sr ions leads to a shift of the Curie point below room temperature. To determine the elastic constants (the Young's modulus E, the shear modulus G and the Poisson's ratio v) of BST, a method of measurement of the longitudinal (ν_L) and transverse (ν_T) ultrasonic wave velocities for this type of material was developed. The structural, dielectric and mechanical properties of BST ceramics were discussed in terms of microstructure and chemical composition

Keywords:

• ceramics
• ferroelectricity
• dielectric properties
• elastic properties

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was partially financed by the European Regional Development Fund under the Infrastructure and Environment Programme [grant number UDA-POIS.13.01-023/09-00].