Field Trapping Properties of $c$-Growth Region in RE123 Melt-Solidified Bulks

We have fabricated Ag-free and Ag-added Dy123 cylindrical melt-solidified bulks with large
c
-growth region. Samples cut from
c
-growth region of each bulk exhibited high
J

_c
up to high magnetic fields and excellent field trapping properties. On the contrary,
J

_c
and field trapping properties in the
a
-growth region were suppressed by subgrain boundaries. Magnetic flux penetration along the subgrain boundaries was confirmed in magneto-optical images of the
a
-growth region. Both
J

_c
and field trapping properties of Dy123 bulks were improved by Ag-addition due to low level Ag substitution for Cu site in the CuO chain.