Dielectric, piezoelectric and ferroelectric anisotropy in grain oriented Aurivillius phase Sr₂Bi₄Ti₅O₁₈ processed by the reactive templated technique

ABSTRACT

Sr₂Bi₄Ti₅O₁₈ ceramics were fabricated using the pre-reacted Bi₄Ti₃O₁₂ and SrTiO₃ powders via solid-state reaction route. These in stoichiometric ratio were uniaxially pressed and sintered at 1130°C for 3 h to obtain textured ceramics. The obtained dense ceramics exhibited crystallographic anisotropy with prominent c-axis oriented grains (Lotgering factor of 0.62) parallel to the uniaxially pressed direction. The resulted anisotropy in the ceramic was attributed to the reactive template-like behavior of Bi₄Ti₃O₁₂ that was used for making Sr₂Bi₄Ti₅O₁₈. Dielectric, ferro and piezoelectric properties measured on the ceramics in the direction perpendicular to the uniaxially pressed axis were found to be superior to that measured in the parallel direction.

KEYWORDS:

• Textured ceramics
• anisotropy
• reactive template
• ferroelectricity
• piezoelectricity

Funding

Tukaram Shet acknowledges AICTE for granting QIP fellowship.