Neutron induced disorder in superconducting A-15 compounds

The effect of high energy neutron (E>1 MeV) irradiation at 60°C on the superconducting critical temperature, Tc, the upper critical field, Hc2, the lattice parameter, ao, and the degree of Long Range Order has been measured for Nb and V based A-IS superconducting compounds. Large reductions in Tc, and Hc2are observed for fluences up to 5.0 × 10¹⁹n/cm². For Nb3Al aoincreases and the degree of Long Range Order is significantly reduced as Tcis depressed. The results are discussed in terms of atomic ordering in the A-15 structure.