0.25 wt% CuO-doped (Li,K,Na)(Nb,Ta)O-3-AgSbO3 lead-free piezoceramics with pure perovskite structure were successfully prepared at a sintering temperature below 1000 degrees C. The sintering temperature of KNN-based piezoceramics was effectively reduced by about 100 degrees C due to the enhanced densification process induced by the addition of CuO. Besides, the acceptable sintering temperature window was broadened by the addition of CuO. It is found that the CuO-doped samples show slightly higher tetragonal-orthorhombic phase transition point (TT-O) but a lower Curie point (T-c), compared to undoped ones. The KNN-based piezoceramics became "hard" as CuO was added, supported by an increase of Q(m). Fairly good electrical properties of d(33)*=383 pm/V, epsilon(r)=860, Q(m)=188 and T-c=215 degrees C could be obtained in dense CuO-modified KNN-based piezoceramics sintered at 970 degrees C, demonstrating promising potential in practical applications. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
1.Chinese Acad Sci, Inst Opt & Elect, Chengdu 610209, Peoples R China 2.Tsinghua Univ, Sch Mat Sci & Engn, State Key Lab New Ceram & Fine Proc, Beijing 100084, Peoples R China
Zhou, Jia-Jun,Cheng, Li-Qian,Wang, Ke,et al. The phase structure and electric properties of low-temperature sintered (K, Na)NbO3-based piezoceramics modified by CuO[J]. CERAMICS INTERNATIONAL,2014,40(2):2927-2931.