Irradiation and mechanical design features of MCFR superconducting magnet system

The authors findings from their analysis and experimental data obtained for the irradiation and mechanical design features of a D-T MCFR superconducting magnet system, are as follows: (1) the irradiation effects on the nuclear and physical properties are: the critical current density decreases as the fast neutron fluence and the magnetic field strength increase, and the upper critical magnet field H/sub c2/ decreases as the transition temperature increases. (2) the critical temperature T/sub c/ decreases as the fast neutron fluence increases. However, the critical temperature recovery for NbTi and Nb/sub 3/Sn can be realized by the suitable annealing temperature and time. (3) the electric resistivity of superconductors and the residual electric resistivity of the structural materials increase with the fast neutron fluence. (4) the changes of mechanical properties and interaction of the structural materials in the superconducting magnet system are embrittlement, reduction in ductility, stress fatigue cracking, stress corrosion cracking, and mechanical integrity in the design