Recent Progress in Application of Internal Oxidation Technique in Nb3Sn Strands

The internal oxidation technique can generate ZrO
₂
nano particles in Nb
₃
Sn strands, which markedly refine the Nb
₃
Sn grain size and boost the high-field critical current density (J
_c
). This paper summarizes recent efforts on implementing this technique in practical Nb
₃
Sn wires and adding Ti as a dopant. It is demonstrated that this technique can be readily incorporated into the present Nb
₃
Sn conductor manufacturing technology. Powderin-tube (PIT) strands with fine subelements (~25 μm) based on this technique were successfully fabricated, and proper heat treatments for oxygen transfer were explored. Future work for producing strands ready for applications is proposed.