Enhancement in magnetic, piezoelectric and ferroelectric properties on substitution of titanium by iron in barium calcium titanate ceramics

Abstract Lead free polycrystalline ceramics with compositional formula Ba 0.90 Ca 0.10 Ti 1–3 x /4 Fe x O 3 (BCT), ( x =0.000, 0.005, 0.010, 0.015 and 0.020) were prepared by the solid state reaction method. The effect of substitution of Fe 3+ ion at Ti-site on the ferroelectric and piezoelectric properties of BCT ceramics was studied. Remanant polarisation ( P r ) and saturation polarisation ( P s ) show an increasing trend while the reverse trend was observed for coercive field ( E c ) with Fe 3+ substitution. The values of the piezoelectric charge coefficient ( d 33 ) and piezoelectric coupling coefficient ( k p ) was found to increase with increase in Fe content. Ceramic sample with x =0.02 was found to have a maximum value of d 33 (130 pC/N) and k p (29%). The prepared ceramic samples show magnetic properties as confirmed by recorded MH loops. On substitution of Fe 3+ ions, the ferroelectric BCT ceramics show clear transformation of the diamagnetic nature of BCT ceramics to weak ferromagnetism.