Optimization of Critical Current Density at 16 Tesla in Nb 3 Sn Superconducting Wires Fabricated in WST

To develop superconducting wires suitable for applications demanding extremely high magnetic fields, we conducted an experimental investigation on the optimization of microstructure and heat treatment processes aimed at enhancing the critical current density (non-CuJc) at 16 T in Internal-tin type multifilamentary Nb3Sn superconducting wires fabricated in WST. Our findings revealed that, under optimal growth conditions characterized by specific time and temperature parameters, where Nb3Sn grain size increased slightly,Hirrdemonstrated a relatively higher value, we obtained significantly enhanced performance at 16 T in these Nb3Sn wires. Specifically, by fine-tuning the Nb3Sn growth condition to 680°C for 80 h, we achieved an impressiveHirrof 27.42 T (4.2 K), and non-CuJcwas elevated to values exceeding 1300 A/mm² (4.2 K, 16 T), accompanied by an atomic percentage of Sn in Nb3Sn reaching 24at.%, conditions conducive to Sn-rich Nb3Sn phases, representing one of the highest performances reported thus far for Ti-doped Nb3Sn wires. We have thus offered a new, scalable route to further study the enhancement ofJcin Nb3Sn wires.