HIGH PIEZOELECTRIC PERFORMANCE AND RELEVANT PHYSICAL MECHANISM OF CuO-MODIFIED Ba(Ti0.96Sn0.04)O3 CERAMICS

Abstract

Ba ( Ti 0.96 Sn 0.04) O 3 and CuO -modified Ba ( Ti 0.96 Sn 0.04) O 3 ceramics were prepared by the solid state reaction technique. Their piezoelectric properties were investigated and compared with those of the recently obtained high-d33 BaTiO 3 ceramic. It has been found that simply substituting Ti 4+ with Sn 4+ worsens severely the piezoelectric properties whereas a combined usage of CuO additive greatly improves the overall piezoelectric performance. CuO -modified Ba ( Ti 0.96 Sn 0.04) O 3 ceramic shows excellent piezoelectric properties of d33 = 390 pC/N , k p = 0.49 and k33 = 0.67 at room temperature. Furthermore, it possesses weak temperature dependences of electromechanical coefficients between -20°C and 55°C and a good thermal aging stability down to a low experimental temperature limit of -50°C and up to 90°C. Detailed analysis suggests that its high piezoelectric performance should be largely ascribed to the ideal microstructure of high relative density and small grains and the corresponding domain configurations.