Direct and converse piezoelectricity of thickness tuned BCZT ceramics: toward efficient bilayered magnetoelectric devices

Abstract

Here we report the effect of thickness reduction of bulk 0.5(Ba0.7Ca0.3)TiO3-0.5Ba(Ti0.8Zr0.2)O3 (BCZT) pellet on its direct and indirect piezoelectric properties. Upon reducing the thickness to 0.3 mm, the pellet shows a very high electrostrain of ~0.7% and piezoelectric coefficient of ~353 pC/N which were ~0.14% and 258 pC/N for the 1 mm thick sample. These results have been correlated with the reduction in hardness and mutual mechanical clamping between the grains due to the reduced thickness of BCZT. Due to this improved strain sensitivity, the bilayered magnetoelectric (ME) devices of BCZT with magnetostrictive CoFe1.9Bi0.1O4 (CFBO) pellet have also shown gradually improved ME coupling coefficient (α_ME) with reduced BCZT thickness (α_ME = 27 and 66 mV·cm-1·Oe-1 for 1 and 0.3 mm BCZT thickness, respectively). This demonstrates the possible applicability of thickness tuned BCZT pellets for various technological purposes.