Dielectric and piezoelectric properties of Sm3+ doped lead barium niobate (PBN) ceramics

摘要： Rhombohedral samarium doped Lead based ceramic materials were fabricated by a high temperature conventional solid state mixed oxide ceramic process. The ceramic composition Pb1-x-3y/2Bax Re3+ y Nb2O6 (x = 0.35 and y=0.00, 0.02, 0.04 and 0.06, Re3+ = Sm3+). The pure and Sm3+ doped lead barium niobate ceramic materials are single phase with rhombohedral(hexagonal) symmetry obtained from powder x-ray diffraction (XRD). The grain size has been measured for all the compositions and lying between 1.60-2.90μm. Broad dielectric peak phase transitions observed with temperature in pure and Sm3+ ion modified lead barium niobate ceramic materials. It is observed that the high values of piezoelectric charge coefficients in d31 and d33 in Sm3+ doped lead barium niobate ceramics. The mechanical quality factor Qm and d33 increases with increase of Sm3+ ion concentration and indicating a highly polarisable lead ion contributing to high Curie temperature dielectric constant.