Characteristics of HTS tube depending on heat-treatment conditions Original Research Article

Bi-2212 HTS tube was fabricated by centrifugal forming process (CFP). As a variation of melt casting process (MCP) or centrifugal casting technique, the CFP is a flexible method for manufacturing Bi-2212 bulk tubes and has been optimized to achieve smooth surface and uniform thickness. At this process, the slurry was prepared in the mixing ratio of 10:1 of Bi-2212 powder and binder. It was initially charged into the rotating mold at the speed of 300–450 rpm. Heat-treatment was performed at the temperature range 870–890°C in air for partial melting. The HTS tube fabricated by CFP at 890°C at the rotating speed of 450 rpm was highly densified and the plate-like grains with more than 20 μm in diameter were well developed along the rotating axis. The measured Tc and Jc at 10 K were around 85 K and 3000 A/cm2, respectively.