Effects of cooling rate on the electrical properties of Pb-free BF-BT ceramics

Abstract

The ferroelectric, piezoelectric and dielectric properties of the air- and water-quenched samples of 0.65Bi_1.05Fe_1-xGa_xO₃–0.35BaTiO₃ (x = 0 and 0.02) lead-free ceramics were investigated. X-ray diffraction patterns showed that the Ga modification and different cooling rates during sintering did not cause any significant change in the crystal structure. It is believed that the significant enhancement of ferroelectric and piezoelectric properties is attributed to the relaxation of the lattice strain induced in the samples, to better understand the quenching effects and thereby improvement in electrical properties, by modification and reduction of associated defects concentration with rapid cooling. For the optimum composition (x = 0.02), an enhanced piezoelectric constant d₃₃ of 156 pC/N was observed from the water quenched sample.

Keywords:

• Lead-free
• dielectric
• ferroelectric
• piezoelectric properties

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF), as funded by the National Research Foundation of Korea (NRF) grant funded by the Ministry of Science and ICT (MSIT) (2018R1A2B6005044). This work was also supported by National Research Foundation of Korea (NRF-2018R1D1A1B07041634).