Effect of CuO and MnO2 on sintering temperature, microstructure, and piezoelectric properties of 0.95(K0.5Na0.5)NbO3–0.05BaTiO3 ceramics

A generalized rule for large piezoelectric response in perovskite oxide ceramics and its application for design of lead-free compositions

“…Modified compositions and solid solutions in the systems ͑Bi, Na͒TiO 3 ͑BNT͒, ͑Bi, K͒TiO 3 ͑BKT͒, BaTiO 3 ͑BT͒, and ͑K,Na͒NbO 3 ͑KNN͒ have received considerable attention as the potential lead-free candidates but reported results are still inferior to that of PZT. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] Design of new lead-free composition is challenging as formulations derived using structure maps, tolerance factor approach, electronegativity factor, and ab initio calculations have not resulted in any promising material. Naturally, the question that comes to mind is "how to design a lead-free composition and predict its approximate piezoelectric response?."…”

Temperature dependence of unipolar fatigue behavior of lead-free alkali niobate ceramics

“…Different amounts of sintering additives CuO and MnO 2 were also tried to suppress the volatilization of Na 2 O by decreasing the sintering temperature. 22) Especially from the industrial perspective, additives are important in order to manufacture samples in large numbers with equal properties. However, certain additives increase the formation of oxygen vacancies, which are a major influence on the electric fatigue behavior of piezoelectric ceramics.…”

Development of KNN-Based Piezoelectric Materials

“…Sintering conditions were optimized for 0.95KNN-0.05BT samples and it was found that muffled samples sintered at 1,060 C for 2 h have the optimum grain size and hence best piezoelectric properties [91]. Different amounts of sintering additives CuO and MnO 2 were also tried to suppress the volatilization of Na 2 O by decreasing the sintering temperature and hence to reduce the leakage current [61]. It was found that addition of 2 mol% CuO and 0.5 mol% MnO 2 reduces the sintering temperature to 950 C and improves the piezoelectric properties with increased d 33 value from 220 pC/N to 248 pC/N.…”