Effect of A-Site Ions Additions on Abnormal Grain Growth and Piezoelectric Properties in NKN-5LT Systems
Dense 0.95(Na0.5K0.5)NbO3-0.05LiTaO3 (NKN-5LT) ceramics, as a candidate for leadfree piezoelectric materials, were developed by conventional sintering process. The effect of additions with A-site ions in perovskite structure on abnormal grain growth and piezoelectric properties in NKN-5LT ceramics was investigated. Sintering temperature was lowered by adding A-site ions as a sintering aid. Abnormal grain growth in NKN-5LT ceramics was observed with varying additions. This grain growth behavior was explained in terms of interface reactioncontrolled nucleation and growth. The electrical properties of NKN-5LT ceramics were investigated as a function of concentration of additions. The electromechanical coupling factor and piezoelectric constant of NKN-5LT ceramics were improved in the samples with A-site ions excess NKN-5LT. These results show that the piezoelectric properties of NKN-5LT samples can be improved by control of the microstructures.
S.-J.L. Kang, M.Y. Huh, N.M. Hwang, H. Homma, K. Ushioda and Y. Ikuhara
M. S. Kim et al., "Effect of A-Site Ions Additions on Abnormal Grain Growth and Piezoelectric Properties in NKN-5LT Systems", Materials Science Forum, Vols. 558-559, pp. 763-766, 2007