To understand the effect of BaCeO3 on a Y2BaCuO5 (Y211) distribution, Y1.5Ba2Cu3Ox (Y1.5) superconductors with/without 1 wt.% BaCeO3 additions were prepared by a top-seeded melt-textured growth (TSMG) process. Two different BaCeO3 powders (as-synthesized (coarse powder) and an attrition-milled (fine powder)) were used and the size effect was compared with that obtained from a Y1.5 sample with no addition. A refinement of the Y211 particles was achieved for both the as-synthesized and attrition-milled BaCeO3 additions. The distribution of the Y211 particles was most uniform in the Y1.5 sample prepared with the attrition-milled BaCeO3 powder due to the reduced size of the Y211-free regions by the fine size BaCeO3 addition. The highest J(c) was achieved in the Y1.5 sample prepared with the attrition-milled BaCeO3 powder. The J(c) result agreed well with the microstructure variations by the addition of BaCeO3 powders. (C) 2009 Elsevier B.V. All rights reserved.