The new route process of V_3Ga mono-cored and multifilamentary wires using high Ga content Cu-Ga compound and V matrix precursor

摘要

V_3Ga compound is one of the attractive low activation materials for high magnetic field superconducting magnet in the several V-based compounds because V-based superconducting materials have shorter decay time of induced radioactivity and high field property above 20 T. V_3Ga compound has not only high upper critical magnetic fields (H_(c2)) above 20 T as well as Nb_3Sn but also better mechanical property. However, the present critical current density (J_c) property of V_3Ga compound wire is insufficiency to apply for large high field magnet such as fusion application. In the previous study, V_3Ga compound wire was mainly investigated "Diffusion process" between Cu-Ga solid solution matrix within 20 at% Ga composition and V filament. Recently, we investigated the new route PIT process using high Ga content Cu-Ga compound to fabricate V_3Ga mono-cored and multifilamentary wires in order to increase a volume fraction of synthesized A15 phase. It was confirmed that the thicker V_3Ga layer formed along the boundary of Cu-Ga powder core and V matrix compared with previous diffusion processed samples in the case of the both mono-cored and mltifilamentary wires. And H_(c2) property of the samples using high Ga content Cu-Ga compounds was increased with increasing of Ga content into Cu-Ga compounds, and it showed about 23.0 T which value was 2.0 T higher than conventional processed samples.