Cryo-permanent magnets-geometry, magnetization and cost issues

High trapped peak magnetic fields obtained for melt-textured 123-high-temperature superconductor (HTS) bulk cylinders, make these materials highly attractive for cryo-permanent magnets (CPMs). However, to transfer the proven performances of HTS materials into practical magnetic devices with magnetizations of /spl les/5 T over /spl ges/10 cm size, issues related to geometry, magnetization and cost have to be addressed. HTS ring structures appear to be more adequate than just cylindrical bulk parts but the demands for growing, shaping and assembling the HTS materials increase. A novel process is introduced to in-situ magnetize the HTS ring using pulsed copper coils. It involves the injection of an extra current which is induced by the magnetizing pulse field. This allows flux penetration into otherwise strongly shielded rings, and thus reduces the required peak magnetic field. Concepts for "medium-size" assembled structures and results of model calculations for corresponding magnetization processes are presented. Preliminary cost comparisons with winding-based solutions are given as well.