A niobium-aluminium (Nb 3Al) coil: performance, including quench behaviour, in the temperature range 4.2–12 K

Abstract

A small coil, wound with a multifilamentry Nb 3Al conductor, was tested over the temperature range 4.2–12 K. The experiment not only encompassed measurements of the conductor's critical currents but also the coil's performance, e.g. 4.8 T (180 A) at 4.2 K and 3.2 T (120 A) at 12 K, and the winding's turn-to-turn normal-zone propagation (NZP) velocities. The coil's stable performance of 120 A at 12 K nearly matched the conductor's short-sample critical current. The coil's terminal voltage and current have also been measured and found to agree well with results of simulation incorporating measured NZP velocities.