Seeded Infiltration and Growth of Bulk YBCO Nano-Composites

The seeded infiltration and growth (SIG) technique offers near-net shape processing of bulk superconductors with significant improvement in reduced
${\rm Y}_{2}{\rm BaCuO}_{5}$
(Y-211) inclusion size, reduced shrinkage, reduced porosity and improved current density compared to samples fabricated by top seeded melt growth (TSMG).
${\rm Y}_{2}{\rm Ba}_{4}{\rm CuMO}_{\rm y}$
phases where
${\rm M}={\rm Nb}$
, Mo, W, Ta, etc., have been shown to form nano-scale inclusions in the
${\rm YBa}_{2}{\rm Cu}_{3}{\rm O}_{y}$
(Y-123) phase matrix and to contribute to enhanced magnetic flux pinning in these materials. In this paper, we describe the introduction of
${\rm Y}_{2}{\rm Ba}_{4}{\rm CuWO}_{\rm y}$
nano-scale inclusions into bulk superconductors processed by the seeded infiltration growth process. Critical current density,
$J_{\rm c}$
, in excess of
$10^{5}\ {\rm A/cm}^{2}$
at 77 K in self-field is observed for samples containing
${\rm Y}_{2}{\rm Ba}_{4}{\rm CuWO}_{\rm y}$
.