Preliminary Investigation on Brazing Performance of OFHC Tube Butt-Joints

The OFHC C10200 tube with an outer diameter of 45mm, and the thickness of 7.5mm was used as the conductor for ITER vertical stabilization (VS) coil. The limited length of the OFHC tube sections require to be connected by induction brazing. A thin BCuP-5 foil with thickness of 0.3 mm and BCuP-5 wire with a diameter of 1.2 mm served as the brazing filler metal. The inert gas of Argon was used for protecting the OFHC tube away from oxidation during induction brazing. An investigation was carried out to observe the brazing performance of OFHC tubes with four kinds of brazing structures. NDE and stretching tests was conducted on the brazed OFHC joints. The results showed that the Butt-OD sleeve joint structure was much easier for operation, and the quality of the brazed joints are better than the others, which was preliminarily chosen for manufacturing the prototype VS coil.