Incorporation of yttrium in barium titanate ceramics

In this work, X-ray diffractometry and scanning electron microscopy techniq ues were used to study the incorporation of yttrium in BaTiO3, with the fol lowing nominal compositions: (Ba1-xYx)TiO3 (0.015 less than or equal to x l ess than or equal to 0.08), (Ba1-xYx)Ti1-x/4(square(Ti))(x/4)O-3 (0.005 les s than or equal to x less than or equal to 0.1), and Ba(Ti1-yYy)O3-delta (0 .028 less than or equal to y less than or equal to 0.258). The phase assemb lage and the lattice parameters indicated a slight solubility (similar to 1 .5 at. %) of yttrium at the Ba sites at 1440 degrees C but a high solubilit y (similar to 12.2 at.%) of yttrium at the Ti sites at 1515 degrees C, When BaTiO3 was heavily doped with yttrium at the Ti sites (a yttrium concentra tion (y) of <0.059), the crystallographic structure was tetragonal, whereas for y greater than or equal to 0.059, the crystallographic structure was c ubic.