Doping Modification On The Microstructure And Properties Of BCZT-base Lead-free Piezoelectric Ceramics

With the special property of electrical-mechanical energy conversion,Piezoelectric is widely used in such field as aerospace,medical,sensors,stage and so on.Lead-free piezoelectric ceramics contains no lead or polluting the environment,accord with the requirement of sustainable development of human society,so the favour of the researchers.In order to improve the Curie temperature of BCZT piezoelectric ceramic,obtaining a better electrical performance of the piezoelectric ceramic,the effects of Sb₂O₃,Bi₂O₃ and BKT dopant on phase structure,micro-structure and electrical properties of BCZT-base ceramics were investigated by using SEM,XRD,Raman detection,TEM,etc.The main conclusions as follow:1.The effect of Sb₂O₃ doping on phase structure,micro-structure and electrical properties of Ba₀.85Ca₀.15Ti₀.9Zr₀.08Sn₀.02O₃ piezoelectric ceramics were investigated.The XRD displays that Sb³⁺ can diffuse into BCZTS lattice and constitute a uniform representative perovskite phase structure sosoloid.The other results show that the BCZTS-xSb samples have dense micro-structure with large grains,distribution well and little porosity when x=0.04 wt.%.And the outstanding properties when x=0.04 wt.% is d₃3=392 pC/N,?_r=4830,tan_?=2.44%;The results of dielectric properties indicate that the highest Curie temperature?Tc?is 102 ? when doping amount of Sb₂O₃ is 0.04 wt.%.2.The effect of Bi₂O₃-doping on phase structure,electrical properties and the dielectric properties of Ba₀.85Ca₀.15Ti₀.93Zr₀.07O₃ piezoceramics were investigated.The experimental data tells that Bi³⁺ diffuse into BCZT lattice and constitute a uniform representative perovskite phase structure sosoloid.When Bi₂O₃ was doped with0.06 wt.%,the best dielectric loss and permittivity of the specimen are 1.2% and 5100,separately.When doping no amount of Bi₂O₃,the best piezoelectric constant is 386pC/N and electro-mechanical coupling factor Kp is 45%;when Bi₂O₃ was doped with0.02 wt.%,the highest T_c=103 ?.3.The effect of BKT-doping on micro-structure,electrical properties of Ba₀.85Ca₀.15Ti₀.93Zr₀.07O₃ piezoelectric ceramics were investigated.The results show that the BCZT-xBKT samples have the outstanding properties when x=0.04 mol;d₃3 =342 pC/N,K_p=57%,?_r=3319,tan_?=2.32%,the Cuire Temperature of?1-x?BCZT-x BKT piezoelectric ceramics increasing to 103 ?.