Effect of a systematic variation of Nd4Ba2Cu2O10 content on the magnetic properties of melt processed NdBa2Cu3O7-delta superconductor

摘要

The effect of a systematic variation of Nd-422 phase content on magnetic properties of melt textured Nd-123 has been investigated. Precisely estimated microstructural parameters such as volume fraction, morphology of Nd-422 particles, and the interface area between the Nd-422 particles and Nd-123 matrix, are correlated to the measured critical current densities. It is found that in the low field region and at higher temperatures, the interfacial pinning by Nd-422 particles is dominant. An anticlockwise tilt observed in the magnetization hysteresis loops at 77 K has been explained by a critical state model in combination with the standard theory of paramagnetism for Nd3+ ions with a Brillouin function. (C) 1998 Published by Elsevier Science B.V. All rights reserved. [References: 34]