Study of superconducting properties in melt textured YBCO levitators

A large number of melt-textured Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-x/ disk-shaped levitators have been manufactured using a seeding technique. Since DC transport current measurement is only capable of characterizing small samples, we have developed a system for measuring the component of the trapped field perpendicular to the surface of the disk (For simplicity, it will be called "trapped field".) and levitation force. The testing system is capable of measuring the distribution of magnetic field as well as the levitation force at the surface of the levitator in a relatively short time period. The magnetic field mapping can also be used to detect the granular microstructure in the levitators. The trapped magnetic fields of these levitators range between 0.45 and 0.65 T, and levitation forces are from 25 and 35 N. Also, the levitation force and the maximum trapped field values are found to correlate with each other.