摘要
High performance piezoelectric ceramics with high Curie temperatures(TC) are the bottle necks of relevant high temperature devices. In this study, the electrical performance and microstructure of Li and Mn codoped Aurivillius-type composite ceramics with a composition Ca_(0.99-x_Bi_(6.99+x)(Li Mn)_(0.01) Nb Ti_5O_(24)(x = 0–0.8) were systematically investigated. The results indicated that uniform intergrowth structure with a lattice similar to that of the end member CBT could be formed at a low x value(x < 0.4). Phase separation occurred when more A-site Ca^(2+) ions were replaced by Bi^(3+) ions. Nevertheless, all composite samples showed d_(33) values about 2 to 3 times of that of the constituent phase Ca Bi_4Ti_4O_(15) and Bi_3 Ti NbO_9 with still a high depolarization temperature. The performance of the samples was found to be related to the density and larger lattice distortion along the polarization a axis. The results also demonstrated that formation of the compound system was an effective way in improving the performance of Aurivillius-type high TC piezoelectric ceramics.
基金
supported by the National Natural Science Foundation of China(Grant Nos.51302015&11574346)
the National Basic Research Program of China(“973”Project)(Grant No.2013CB632900)
the Overseas Talent Foundation of Beijing Academy of Science and Technology(Grant No.OTP-2013-001)
the Open Foundation of the State Key Laboratory of New Ceramics and Fine Processing of Tsinghua University
