Fabrication and characterization of BNLT-BHF lead-free ceramics

ABSTRACT

The solid solution of (1-x)Bi_0.4871Na_0.4871La_0.0172TiO₃-x(Bi_0.95Ho_0.05)FeO₃ ((1-x)BNLT-xBHF) with x = 0.03–0.09 lead-free ceramics was prepared by the conventional solid-state reaction route. Mixed powders were calcined at 900°C for 4 h. The ceramics were sintered at 1150°C which was the optimum sintering temperature. Densification, phase and microstructure were characterized via Archimedes' method, X-ray diffraction technique and scanning electron microscopy, respectively. The bulk density data of the studied ceramics showed that the concentration of BHF in (1-x)BNLT-xBHF solid solution improved densification of this ceramic system. Only single perovskite phase was observed in XRD patterns of the sintered samples for all conditions. The SEM micrographs for samples with low concentrations of BHF were homologous and smaller grain size than when increasing the concentration of the BHF. The correlation of the properties and the concentration of BHF of these studied ceramics are discussed and compared with other ferroelectric ceramics.

KEYWORDS:

• Solid solution
• phase
• microstructure

Funding

This study was financially supported by Chiang Mai Rajabhat University, National Research Council of Thailand (NRCT), and Rajamangala University of Technology Phra Nakorn. Thanks also to Faculty of Science and Technology Chiang Mai Rajabhat University, Faculty of Science and Technology, Rajamangala University of Technology Phra Nakorn and Faculty of Science Chiang Mai University for supporting facilities.