Properties of NaCu3Ti3NbO12 based-ceramics doped with nanopowders

Abstract

In this work, the properties of NaCu3Ti3NbO12 based ceramics preparing by mixed oxide method were studied. The starting materials including Na2CO3, CuO, TiO2 and Nb2O5 were mixed by ball milling for 24 hours with stoichiometry, calcined at 950 °C for 24 hours and were doped with (0–2.0 vol%) MgO, Al2O3 and ZrO2 nanopowders. Then, the mixed powder was pressed into a disc shape. The green bodies were sintered at 975–1025 °C for 10 hours. Phase formation was investigated by XRD and microstructure by SEM. The body-centered cubic perovskite-related structure of space group Im-3 and small amount of second phase were detected. The normal grain growth is observed and shown rectangular grain shape. Density of the sintered samples was measured by Archimedes’s method using distilled water as the fluid medium. The highest density of NCTNO and NCTNO/Al2O3 ceramics were found at 1025 °C sintered temperature and 1000 °C for NCTNO/MgO and NCTNO/ZrO2 samples. Dielectric constant of the samples was examined using an LCR meter and the mechanical properties of samples were investigated by Vickers microhardness tester. The addition of nanopowders can be improved the mechanical property and 1.0 vol%ZrO2 doping sample showed the highest the dielectric constant.