Ferroelectric and piezoelectric properties of (Ba<inf>0.7</inf>Ca<inf>0.3</inf>)(Ti<inf>1&#x2212;x</inf>Sn<inf>x</inf>)O<inf>3</inf> lead-free ceramics

Abstract

The ferroelectric and piezoelectric properties of Sn ⁴⁺ modified (Ba _0.7 Ca _0.3 )(Ti _1-x Sn _x )O ₃ , (with x = 0.000 to 0.100 in steps of 0.025) lead free electroceramics were investigated. With Sn ⁴⁺ substitution, a structural phase transition from pure tetragonal to pseudo-cubic structure has been observed; which strongly influence the ferroelectric/ piezoelectric nature of the samples. At room temperature, all the samples exhibit typical polarization-electric field hysteresis as well as field induced strain butterfly loop which confirms the ferroelectric and piezoelectric nature. As Sn ⁴⁺ content increases, the ferroelectric properties seems to be suppressed while the piezoelectric properties gets improved up to x = 0.075 and then decreased. Moderately high remanent polarization (P _r ) and low coercive field (E _c ) were observed for all compositions, which may be essential for storage and switching applications.