SS Helium Vessel Development for 1.3 GHz SRF Cavities at Fermilab

As part of its SRF Cavity Development efforts, Fermilab is developing a stainless steel helium vessel as an alternative to the current titanium vessel. Stainless steel (SS) components will be less expensive, easier to manufacture, and not require controlled atmosphere welding. Several obstacles exist which Fermilab engineers believe can be overcome in a way that does not require active tuning of the cavity during the cool down process. The major obstacles and solutions are presented here.