中文摘要：

采用传统固相烧结法制备了0.7BiFeO3-0.3BaTiO3-xBi2O3（0≤x≤0.05）无铅压电陶瓷,研究了Bi补偿量x和冷却方式对其相结构、微观形貌和综合电学性能的影响。结果表明：所有样品均为菱方相（R）和伪立方相（PC）两相共存,0≤x≤0.01样品为纯的钙钛矿结构,且x=0.01样品的两相比例CR/C（PC）接近1;x〉0.01样品中出现富Bi杂相Bi（25）FeO（40）。与冷却方式相比,优化Bi补偿量更有利于提升BFBT-xBi2O3陶瓷的压电性能。随着x增大,d33先增大后减小,在x=0.01时获得最优值。由于较小的晶粒、较合适的CR/C（PC）以及较大的残余应变,水冷BFBT-0.01Bi2O3陶瓷获得了最优的压电性能（d（33水冷）=141 p C/N、kp=27%）和高TC=507℃。研究结果表明,BFBT基陶瓷有希望成为兼具高压电性能和高TC的无铅压电材料体系之一。

英文摘要：

A series of 0.7BiFeO3-（0.3）BaTiO3-xBi2O3（0≤x≤0.05） ceramics were prepared with solid reaction method under furnace, air and water cooling. The effects of excess Bi and cooling methods on phase structure, morphology and comprehensive electrical properties were investigated. All the ceramics show coexisting R-PC phase whose ratio CR/C（PC） is close to 1 at x = 0.01, apart from the appearance of an impurity phase Bi（25）FeO（40） when x0.01. Compared with cooling way, optimizing excess Bi content is more beneficial to enhance the piezoelectric performance of BFBT-x Bi2 O3. The d（33） firstly increases and then decreases with x increment, and gets an optimal value at x = 0.01. Smaller grain size and suitable CR/C（PC）, larger residual strain all contribute to the enhanced piezoelectricity（d（33）=141 p C/N, kp=27%） and a high Curie temperature（TC = 507℃） in water-cooled BFBT-0.01Bi2O3 ceramic. The present work indicates that BFBT based lead-free piezoelectric ceramics are promising candidates for high temperature applications with both high performance and high TC.