Microstructure and piezoelectric properties of CuO-doped 0.95(K0.5Na0.5)NbO3-0.05Li(Nb0.5Sb0.5)O3 lead-free ceramics

The effects of sintering temperature and the addition of CuO on the microstructure and piezoelectric properties of 0.95(K0.5Na0.5)NbO3-0.05Li(Nb0.5Sb0.5)O-3 were investigated. The KNN-5LNS ceramics doped with CuO were well sintered even at 940 degrees C. A small amount of Cu2+ was incorporated into the KNN-5LNS matrix ceramics and XRD patterns suggested that the Cu2+ ion could enter the A or B site of the perovskite unit cell and replace the Nb5+ or Li+ simultaneously. The study also showed that the introduction of CuO effectively reduced the sintering temperature and improved the electrical properties of KNN-5LNS. The high piezoelectric properties of d(33) = 263 pC/N, k(p) = 0.42, Q(m)= 143 and tan delta=0.024 were obtained from the 0.4 mol% CuO doped KNN-5LNS cerlunies sintered at 980 degrees C for 2h. (C) 2011 Elsevier Ltd. All rights reserved.