We have developed Fiber-Reinforced-Superconductors (FRS) for an application of high-field pulsed magnets. FRS is a superconducting filament reinforced with a fiber of high-elastic modulus. Tungsten fibers have been used as reinforcement so far. On the other hand, tantalum or titanium fiber has relatively high elastic modulus (even though each is lower than that of tungsten), and moreover, each fiber is expected to function as a resource to supply tantalum or titanium element into Nb
3Sn during the thermal diffusion process, which will improve the superconducting properties. Hence we prepared FRSs with tantalum and titanium fibers to measure their superconducting properties. The results of
Tc and
Jc measurements show that the FRS using the titanium fiber has low critical temperature compared to the FRS with a tungsten fiber. We suppose that this is caused by excessive addition of titanium into Nb
3Sn. On the other hand, critical current density and upper critical field of the FRS using tantalum fiber are improved because of appropriate supply of tantalum into Nb
3Sn. The superconducting characteristics are studied with taking intrinsic strain in Nb
3Sn layers into consideration.
抄録全体を表示