Fusion neutron irradiation effects in commercial Nb3Sn superconductors

Radiation Limits for Nb{sub 3}Sn Superconductors for ITER Magnets: A literature review

“…Some of these newer materials are currently in the procurement process for ITER prototype coils (Table 1.3.1). The 14-MeV results of Hahn et al [1991] on ternary Nb3Sn were .…”

“…Hahn et al suggested that both of these Tieffects arose from initial strain. They noted that the lattice parameter had been found to increase by O.1%/K of TC depression in both foils and multifilamentary specimens [citations, Hahn et al, 1991]. [ 1978] shows the results of l-h anneals at the indicated temperatures on diffusion specimens irradiated with a particles and protons at 100"C. Kodaka et al [1985] shows the recovery process for in situ Nb3Sn wires and multifilamentary Nb3Sn wires produced by the bronze process.…”

“…Brown et al [1978b] reported an irradiation-temperatureeffect for binary Nb3Sn with a JC of 2 x 104 A\mm2 at 5 T, but no effect for material with a lower JC of 8 Table 2.1 for specifications. From Hahn et al [1991].…”

“…From analysis of the data of Hahn et al [1991], Summers et al [1991] expressed the change in TC as a function of damage energy, ED:…”

“…After 14-MeV irradiation, Hahn et al [1991] found that the degradation point for JC occurred at about 2 to 3 x 1022/m2(E = 14 MeV) [ED > -0.6 eV] when several types of commercial, binary Nb3Sn composites were tested after both ambient and cryogenic irradiation (Figure 3.4.7). Use of the ratios shown in The use of ternary conductors is probably necessary to achieve the performance required in ITER (Table 1.3.1).…”