Determination of compositional fluctuation region in solid solution of lanthanum-modified lead zirconate titanate

A method was developed to determine a compositional fluctuation region in P b1-yLay(ZrxTi1-x)(1-(y/4))O-3 (PLZT) solid solution in the tetragonal regio n. The compositional fluctuation in PLZT extends two-dimensionally on the p hase diagram. The method described in this paper utilized the fact that the compositional fluctuation region extends to the composition lines whose la ttice spacing corresponds to the higher or lower fluctuation limit. The flu ctuation limits of the lattice spacings were estimated from X-ray diffracti on analysis. This method revealed that the compositional fluctuation in PLZ T is difficult to be eliminated by using a conventional dry method (mixed o xide method). The shape of the region indicated that homogenization of Zr4 and Ti4+ was more difficult as compared with that of Pb2+ and La3+. (C) 20 01 Kluwer Academic Publishers.