Influence of Composition on Properties of BNT-BT Lead-Free Piezoceramics
摘要
Lead-free piezoelectric ceramics of (Bi1/2Na1/2)TiO3-BaTiO3(BNT-BT) were prepared by the conventional piezoelectric ceramic preparation technique (free air atmosphere sintering). The influence of BaTiO3 additive amount and La2O3 additive amount on the properties of BNT-BT lead-free piezoceramics were investigated. The results show that the dielectric constant(e) and piezoelectric strain constant(d33) of materials start increasing and then decreasing while BaTiO3 additive amount increasing, the e and d33 of materials have maximum value (e=1650, d33=120 PC·N-1) while x(BaTiO3)=0.06 mol. The e and d33 of materials start increasing and then decreasing while La2O3 additive amount increasing, the e and d33 of materials have maximum value (e=1684, d33=153 PC·N-1) while w(La2O3)=0.3%. The influence of La2O3 additive amount on the microstructure of BNT-BT piezoelectric ceramics was analysed by SEM(scanning electron microscope). The influence mechanism of La2O3 additive amount on the properties of BNT-BT piezoelectric ceramics was discussed. The BNT-BT ceramics with optimum comprehensive properties were obtained.