Electro-Mechanical Problems in Superconducting Coils

This paper presents the most recent research activity performed by the authors in the field of contact problems in superconducting coils. The research is related to the development of the coils for the experimental nuclear fusion machine “ITER”. The results here summarized are related to the inter-strand electromechanical behavior and its dependence on the electromechanical contact resistance. The effects related to the distribution of the superconducting zones within the wire, and of the mechanical properties of the materials are presented. Moreover a microscopical formulation for a more accurate treatment of the contact resistance is formulated. The adopted strategy is based on the statistical characterization of the surface roughness and the electro-mechanical behavior of the contacting asperities. In such a way the contact resistance is build up starting from a physical background.