R&D of the key components for ITER magnet supports

In this article, we report the recent progress of the R&D work for ITER magnet supports, including 316LN raw material development, designing and manufacturing, development of gravity supports (GS) and poloidal field (PF) supports. 316LN stainless steel has been developed successfully with nitrogen content up to 0.188 mass%. These materials show very good mechanical properties at both room temperature and low temperature. The GS conceptual design using welded connections is replaced with pre-stressed bolted connections in order to reduce the risk of defects and manufacturing cost. The finite element model (FEM) analysis for this design shows that neither terrible stress concentrations nor large deformations would occur during either normal or abnormal operation. Attaching the thermal anchor to the flexible plate is made possible by a brazing connection and is carried out in the GS manufacturing. For PF supports, the wear resistance of the strut dowel of PF3-4 support improved after ion implantation. (C) 2010 Elsevier B.V. All rights reserved.