Study on OFC Electron Beam Welding Joints in a Boat Shape RF Cavity

Proton beam accelerators with an energy of ~GeV and a power of ~MW have been developed to expand the application of protons in basic physics, the nuclear industry, family safety, and so on. The high-power radio frequency (RF) cavity is an extremely important component of proton accelerators. To study the manufacturing process of the high-power RF cavity, the Research and Development of the 1/4-scaled boat-shaped cavity is being developed. The selection of copper material and the performance of the welded joint are the key factors of the boat-shaped cavity. In this article, taking 6 mm thick Y-state and semi-Y-state oxygen-free copper (OFC) as the research objects, the microstructure and mechanical properties of the electron beam welded joints of these materials were compared and analyzed. In contrast, a semi-Y OFC is more suitable for the manufacturing and welding of boat-shaped RF cavities, and has been applied to the manufacturing of the 1/4-scale boat-shaped cavities.