MEASUREMENT OF TRANSPORT CRITICAL CURRENT OF Y-BA-CU-O USING AN INDUCTIVE METHOD

An inductive, contactless procedure (discussed in Harris, et al. [1] was used to measure two samples of Y-Ba-Cu-O, one of which was conventionally sintered, the other prepared using a melt-processing technique. When made into ring form and placed as a tertiary winding on a transformer, the sample could be driven to the normal state and a critical current density determined. It was shown that the melt-processed material has a very large critical current density when compared with the conventionally sintered material, and exhibits an instantaneous transition to the fully normal state at a well-defined current level. It also shows a propensity to degrade rapidly in the presence of moisture.