Effect of Zr(4+) substitution on thermal stability and electrical properties of high temperature BiFe(0.99)Al(0.01)O(3)-BaTi(1-x)Zr(x)O(3) ceramics

High-temperature Pb-free ceramics of 0.72BiFe(0.99)Al(0.01)O(3)-0.28BaTi(1-x)Zr(x)O(3) (BFA-BZ(X)T) have been prepared through solid state reaction route. The influence of the Zr(4+) substitution for Ti(4+) on microstructure, thermal stability and electrical properties of the BFA-BZ(X)T ceramics was investigated. The results showed single-phase solid solutions occurred for compositions x = 0-0.12 and a morphotropic phase boundary (MPB) separating rhombohedral and pseudocubic phases existed near x - 0.03. The substitution of Zr(4+) for Ti(4+) caused significant change of grain size for BFA-BZ(X)T ceramics. The optimum piezoelectric properties of d(33) = 157pC/N, k(p) = 0.33, combined with improved depoling temperature T(d) = 425 degree C, are obtained around the MPB composition of x =0.03. The results indicate that BFA-BZ(X)T ceramics have a great potential to apply in high temperature field.