ENERGY-DISPERSIVE X-RAY-ANALYSIS OF A Y2BACUO5 GRAIN INSIDE A TYPICALMELT-TEXTURED GROWTH YBA2CU3OY SUPERCONDUCTOR

'Y-deficient phase' has been found around the non-superconducting Y2Ba CuO5 (Y-211) grains in the melt-textured growth (MTG) YBa2Cu3Oy (Y-123 ) superconductor using energy dispersive X-ray analysis (EDX). This re sult shows that the effective volume of non-Y-123 grain (which might a ct as magnetic flux pinning centre) should be greater than that of the visible one. According to the MTG crystal growth concept developed re cently, the formation of such a 'Y-deficient phase' may be due to the crystallization of unreacted Ba and Cu rich liquids near the boundary of the Y-211 grain during the crystal growth process.