@article{afe6883874954ad09af9214098795724,
title = "Effects of post-annealing on electrical properties of CuF2·xH2O-doped KNN ceramics for rotary-linear ultrasonic motors",
abstract = "Lead-free (K0.5Na0.5)NbO3 (KNN) ceramics were prepared using a novel sintering aid (CuF2·xH2O (x ≈2)) to investigate the effects of post-annealing temperature and atmosphere on oxygen vacancies, microstructure, and electrical properties. Post-annealing (K0.5Na0.5)NbO3 + 1.5 mol% CuF2·xH2O (KNNCH) ceramics at 800 °C under argon was shown to increase the bulk relative density to 97% through the formation of a homogeneous microstructure with liquid phase. The resulting samples presented the following excellent piezoelectric properties: kp：34.1% (±2%); kt：45.3% (±2%); Qm：3170 (±2%); Rz：8.6 Ω (±3%); and tanδ：0.1%. Our results clearly demonstrate that annealing under argon can produce oxygen vacancies in ceramics, which has a significant influence on the stability of domain structures of the samples. Piezoelectric motors fabricated using these ceramics achieved a velocity of 4.5 mm/s, vertical velocity of 3.02 ·mm/s, and output power of 2.93 mW with a negligible increase in temperature and high stability while driven.",
author = "Weng, {Chung Ming} and Tsai, {Cheng Che} and Hong, {Cheng Shong} and Chiang, {Chung Hao} and Chu, {Sheng Yuan} and Lin, {Chun Cheng} and Jyh Sheen",
note = "Funding Information: We gratefully acknowledge the financial support provided from the Ministry of Science and Technology (MOST), Taiwan, ROC. (Grant numbers: MOST 106-2218-E-006-023, MOST 106-2221-E-006-226, MOST 106-2622-E-006-019-CC3, MOST 106-2221-E-272-003). We would also like to thank Ms. Yu Shan Cheng (National Yang-Ming University, Taiwan) for assistance in the experiments during the preparation of this paper. Funding Information: We gratefully acknowledge the financial support provided from the Ministry of Science and Technology (MOST), Taiwan, ROC . (Grant numbers: MOST 106-2218-E-006-023 , MOST 106-2221-E-006-226 , MOST 106-2622-E-006-019-CC3 , MOST 106-2221-E-272-003 ). We would also like to thank Ms. Yu Shan Cheng (National Yang-Ming University, Taiwan) for assistance in the experiments during the preparation of this paper. Publisher Copyright: {\textcopyright} 2018 Elsevier Ltd and Techna Group S.r.l.",
year = "2018",
month = oct,
day = "1",
doi = "10.1016/j.ceramint.2018.05.156",
language = "English",
volume = "44",
pages = "16173--16180",
journal = "Ceramics International",
issn = "0272-8842",
publisher = "Elsevier Limited",
number = "14",
}