Microstructure and electrical properties of Bi1/2Na1/2TiO3-BaTiO3-Y2NiMnO6 lead-free piezoelectric ceramics

Lead-free ceramics (1-x-y) Bi1/2Na1/2TiO3-xBaTiO3-yY2NiMnO6 (BNT-BT-YNMO-x/y) were prepared by conventional solid-state reaction method and their structure and electrical properties were systematically investigated. The X-ray diffraction patterns showed that all the samples exhibit a pure perovskite phase with rhombohedral structure. All the modified ceramics with a clear grain boundary and uniformly distributed grain size were observed in SEM images. Either increasing x or y content can enhance ferroelectric and piezoelectric properties. The optimum electrical properties can be obtained at x=0.065 and y=0.002, which are as follows: P-r=38.05 mu C/cm(2), E-c=21.42 kV/cm, d(33)=219 pC/N and k(p)=29.5%. The results indicate that the BNT-BT-YNMO-x/y ceramics are promising lead-free piezoelectric candidates for practical applications. (C) 2015 Published by Elsevier Ltd and Techna Group S.r.l.