Single-Grain Bulk YBa2Cu3Oy Superconductors Grown by Infiltration Growth Process Utilizing the YbBa2Cu3Oy + Liquid Phase as a Liquid Source

The top-seeded infiltration growth (IG) processed YBa2Cu3Oy (Y-123) has several advantages compared to the same material produced by other melt process techniques. There is usually no shrinkage, a limited number of pores, and an uniform secondary phase particle dispersion in the Y-123 matrix. These characteristics of the IG process are very attractive for several industrial applications. In this paper, we produced a large single-grain Y-123 by IG and top seeded melt-growth process. Utilizing commercial YbBa2Cu3Oy (Yb-123) and a homemade Y2BaCuO5 (Y-211), we produced bulk YBa2Cu3Oy samples using Yb-123 + liquid (1:1) as a liquid source. Four facet lines on the top surfaces of the as-grown samples indicated a uniform growth from the seed up to sample edges. Magnetization measurements by SQUID magnetometer showed a sharp superconducting transition with Tc,onset at 92.1 K. The critical current density at 77 K and self-field was 39,000 A/cm2. Trapped field results confirmed that single grain Y-123 samples were produced utilizing the above process. Our results prove that Yb-123 + liquid (1:1) as a liquid source is effective in producing single grain Y-123 material by IG process.