We investigate the spatial variation in the superconducting properties of Nd-Ba-Cu-O/Ag large grains fabricated by a top-seeded melt growth process in controlled partial oxygen pressures of 0.01 atm and 0.001 atm. The results of magnetic measurements show that superconducting transition temperature and critical current vary with position in a large sample. It is found that such spatial variation in magnetic properties can be reduced when a sample is grown under a low oxygen partial pressure. It is also found that trapped field distributions of Nd-Ba-Cu-O/Ag large grains reflect their spatial variations in the magnetic properties. In order to enhance the trapped field, it is necessary to optimize the local magnetic properties in the vicinity of the central axis in large-grain materials.
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