Effect of Pt and CeO2 on Growth of Y-123/nano-Y2O3 Single Grain Superconductors

Abstract

The top seeded melt growth (TSMG) process is used widely to grow single grain, bulk superconductors for high field engineering applications. Within the TSMG process, the flux pinning ability of a single-grain bulk superconductor can be improved effectively by reducing the size of starting precursor powders prior to melt processing. This paper investigates the preparation of Y-123/nano-Y <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> single-grain samples based on TSMG process. A large number of microcracks and significant inhomogeneity were found in samples containing Pt and CeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> additives, respectfully. This reduces the performance of samples made from nano Y <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> starring powders. A pretreatment of the starting powders was developed to decrease microcracks and improve the homogeneity of Y-123/nano-Y <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> single grain samples. The influence of Pt and CeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> doping on the superconducting properties of the fully processed single grain were also investigated in detail. The Y-123/nano-Y <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> based samples exhibit features that are rarely seen in conventional YBCO single grain, bulk superconductors.