Superconductors and joints, tests and trends for future development

The evolution of superconductors for fusion research is introduced with a review of a few relevant milestones of the last 25 years. The cable-in-conduit conductors (CICC) are the most promising option for future fusion devices. The design aspects and test results of the International Thermonuclear Experimental Reactor (ITER) CICCs and joints in SUpraLeiterTestANlage (SULTAN) are discussed paying special attention to the interstrand resistance, current redistribution, transient stability and hydraulic behavior. The challenges for future development are identified in the cost reduction and reliability issue.