Improvement of the superconducting properties of an infiltrated YBCO bulk superconductor by a BaCeO3 addition

Abstract

Single grain YBa2Cu3O7-x (Y123) bulk superconductors with Y2BaCuO5 (Y211) and various amounts of BaCeO3 (5-45 wt.% by an increment of 10 wt.%) were fabricated by a seeded infiltration process. The addition of BaCeO3 was found to be effective for a modification of the microstructure and an improvement of the superconducting properties. The refinement effect for Y211 particles within an entire superconducting YBa2Cu3O7-x (Y123) matrix was achieved by BaCeO3 additions. The critical current density (J(c)) values were increased as the BaCeO3 contents were increased (maximum J(c) at 35 wt.% BaCeO3 addition). The J(c) improvement by BaCeO3 additions might be due to the microstructure modifications associated with the finely distributed Y211 and BaCeO3 particles. With the addition of BaCeO3 the onset T-c values decreased slightly, indicating highly limited Ce substitution for Y site. It can be concluded that the BaCeO3 addition has a beneficial effect on the morphology, the size and the distribution of the Y211 inclusions and the microstructure regarding pinning improvement. (C) 2009 Elsevier B.V. All rights reserved.