Speaker
Description
The record Jc of commercial Nb3Sn conductors has been at a plateau since the early 2000s; however, much higher Jc than the state of the art is required for building the high-field accelerator magnets in future energy-frontier circular colliders. In the past few years a new type of Nb3Sn conductor with artificial pinning centers (APC) based on the internal oxidation method has demonstrated significantly superior performance relative to the state of the art. In 2019 the APC conductors we developed first reached the non-Cu Jc specification required by the 16 T dipole magnets for the proposed Future Circular Collider (FCC)-hh. Since then our efforts have been mainly focused on pushing the APC strands toward readiness for practical applications, and great progress has been made. It was also found that this method not only significantly improves non-Cu Jc at high fields (e.g., above 10 T), but also dramatically reduces persistent-current magnetization at low fields (e.g., below 3 T) relative to the restacked-rod-process (RRP®) conductors due to the point pinning behavior. In this talk the opportunities, challenges, current status and future plans for the APC Nb3Sn conductors will be discussed.
