EXTRUSION OF MULTILAYER SUPERCONDUCTOR COILS

This paper describes bulk processes that have been applied to the fabrication of multilayer superconductor coils from the YBa[sub 2]Cu[sub 3]O[sub x] (YBCO) superconductor. In particular, three important aspects of fabricating multilayer YBCO coils are discussed. First is a discussion of the properties of Y[sub 2]BaCuO[sub 5] (211) that make it a suitable insulator for coating YBCO and a description of how the coating is applied in a continuous extrusion process. Second is a description of improvements in the mechanical properties of YBCO that result from the addition of Ag as a second phase and a discussion of the importance of these additions during the firing of multilayer coils. Third, and perhaps most important, is the description of the heat treatment of the coils.coils.