Piezoelectric and ferroelectric properties of rare-earth modified filled tungsten bronze barium silver niobate ceramics

Abstract

Ceramics of Ba_4–2xAg_2+xLn_xNb₁₀O₃₀ where x = 0.0; 0.1; 0.3; and 0.5; Ln = Gd, Dy were prepared by conventional powder mixing method. XRD patterns of these materials indicated them to be orthorhombic. Substitution of rare-earth into barium silver niobate yielded a higher room temperature dielectric constant but lowered the Curie temperature from 415°C to 118°C with a significant decrease in the peak dielectric constant also. Rare-earth substituted samples showed higher electromechanical coupling coefficients. The micro-structure of these samples was studied by a scanning electron microscope.