High temperature mechanical properties and high strength sheaths for powder-in-tube tapes

While conventional powder-in-tube tapes approach commercial application, new directions are being developed to improve the process. Here, two advances from conventional silver/BSCCO powder-in-tube are discussed: high-temperature mechanical deformation and high strength sheaths. Direct measurements of the constituent mechanical properties are reported. Preliminary results for titanium sheathed 2212 tapes are also reported. It is shown that hot-rolling and high strength sheaths are each important directions for future research. Furthermore, as hot-rolling improves the microstructure at the center of the core and high strength sheaths improve the sheath/superconductor interface, these two directions are synergistic.