Solid State Ionics, Vol.180, No.4-5, 320-325, 2009
Anisotropic properties in textured lead barium niobate compositions around the morphotropic phase boundary
Partially textured PbxBa1-xNb2O6 ceramics, with compositions around the morphotropic phase boundary, were obtained by the hot forging technique. Scanning electron microscopy revealed that the grains were arranged with their lengthwise direction preferentially in the direction of the forging. From the differences of the X ray diffraction profiles between the samples analyzed in the direction of forging and those analyzed in the pressing direction it was possible to confirm the crystallographic growth habit of the PBN ceramics for the tetragonal and orthorhombic symmetry compositions. The identification of a mixture of tetragonal and orthorhombic symmetry phases in a whole range of studied compositions was also possible. The phase transformation around the morphotropic phase boundary (in this case, tetragonal (4mm) to orthorhombic (m2m)) could be analyzed through the direction change of the polarization vector in partially textured PBN ceramics. (C) 2009 Elsevier B.V. All rights reserved.