Physical Properties of New, Lead Free BaTi1 - x(Nb0.5Yb0.5)xO3 Ceramics.

New lead free ceramics derived from the ferroelectric material BaTiO3 by substituting Ti4 + by Nb5 + and Yb3 +. The dielectric and ferroelectric properties were studied. The compositions BaTi1 - x(Nb0.5Yb0.5)xO3 display a classical ferroelectric (0 ≤ × < 0.1) and relaxor ferroelectric behaviour (0.1 ≤ × ≤ 0.2). BaTi0.9(Nb0.5Yb0.5)0.1O3 specimen present a relaxor behaviour at a temperature close to room with high permittivity (ε'r = 9500 at 1 kHz), which opens the way for possible use of it for capacitor applications. The polarisation hysteresis loops were observed of relaxor BaTi0.875(Nb0.5Yb0.5)0.125O3 specimen. The ceramic BaTi0.9(Yb0.5Nb0.5)0.1O3 provides a piezoelectric constant d31 of about 11.17 pC/N near room temperature. [ABSTRACT FROM AUTHOR]