A15 Nb
3Al has gained much interests for high-field and large-scale applications due to its excellent critical current density
Jc and strain tolerance. However, the shift of Nb
3Al composition from stoichiometry at temperatures below 1800°C causes difficulties in the fabrication of conductors with inherent Nb
3Al characteristics. In this study, Nb
3Al powders prepared by arc melting in an Ar / H
2 atmosphere were encased in a sheath and fabricated into tapes through the ex-situ PIT (Powder in Tube) process. The present study revealed that the oxygen content in the Nb
3Al powder plays a crucial role in yielding large
Jc in the tape. Furthermore, the addition of Ag powder to the Nb
3Al powder was found to appreciably enhance the
Jc of the tape in lower fields. The superconducting performance of the tapes is discussed in relating to their structures.
View full abstract