DESY, Hamburg, Germany
For research in the field of heat treatments of supercon-ducting cavities, a niobium ultra-high vacuum furnace built in 1992 - originally used for the titanization of 1.3 GHz nine-cell cavities - and later shut down was recently refurbished and reactivated. A significant upgrade is the ability to run the furnace in partial pressure mode with nitrogen. The furnace is connected directly to the ISO4 area of the clean room for cavity handling. At room temperature vacuum values of around 3×10-8 mbar are achieved. The revision included the replacement of the complete control system and a partial renewal of the pump technology. The internal mounting structures are optimized for single-cell operation including tandem operation (two single-cell cavities at once) and corresponding accessories such as witness-samples and caps for the cavities. The installation of additional thermocouples for a detailed monitoring of the temperature curves is also possible at the mounting structure. Due to the furnace design, its location and the strict routines in handling, very high purity levels are achieved in comparison to similar setups and hence provide a mighty tool for SRF cavity R&D at DESY.
