Abstract:  Dimensional accuracy and mechanical properties for U-shaped supporting clamps for ITER magnet support (PFCS2), fabricated with the welding process and the integral ring forging plus wire-electrode cutting process respectively, were studied. The final dimension of U-shaped clamp, manufactured by double-sided TIG welding and single-sided TIG welding of components with the help of various auxiliary tools and heat treatment, can be controlled within the required range, but the impact of the welds at 77K is less than 100J. By adopting the integral ring forging plus slot wire-electrode cutting process, the opening size and slot size of the U-shaped clamp can meet the tolerance requirements, meanwhile, the consistency of the material properties is guaranteed, and the mechanical properties of the U-shaped clamp are improved. The integral ring forging plus wire-electrode cutting process is finally recognized by ITER International Organization (IO) as the mass production method for U-shaped clamps.

Key words:

 ITER, U-shaped clamp, TIG welding, Integral ring forging, Wire-electrode cutting

摘要： 通过焊接和“整体环形锻造+线切割”两种制造方案对ITER磁体支撑U型支撑夹(PFCS2 U)的制造进行了研究。在采用TIG焊接方案时，通过对组件进行双面和单面焊接，结合多种辅助工装和热处理，最终可将尺寸控制在要求范围内，77K时焊缝的夏比冲击性能低于100J；在采用“整体环形锻造+狭缝线切割”的制造方案时，U型支撑夹的开口尺寸和狭缝尺寸均满足公差要求，同时保证了U型支撑夹的材料性能的一致性，提高了U型支撑夹的力学性能。“整体环形锻造+狭缝线切割”最终获得ITER国际组织(IO)的认可，并应用到U型支撑夹的批量生产中。

关键词: ITER, U型支撑夹, TIG焊, 整体环形锻造, 线切割