Investigation of the Cu based binary alloys and the internal matrix reinforcement bronze processed Nb3Sn wires

Abstract

Mechanical strength improvement on Nb3Sn wire is the most important research subject to realize high field magnet applications operated under higher electromagnetic force environment. Recently, we approached to the internal matrix reinforcement technique due to the solid solution mechanism using ternary bronze alloy matrix on the bronze processed Nb3Sn wire. In this study, the effect of the solute element on the mechanical property of the matrix after Nb3Sn synthesis heat treatment was evaluated. Several Cu based binary alloys were casted, and these alloys were sintered in order to demonstrate the matrix after Nb3Sn synthesis. We confirmed that the both 0.2% proof stress and ultimate tensile stress of the Cu-In alloy was higher than those of the pure Cu and Cu-Zn alloy. The mechanical strength improvement due to the internal matrix reinforcement using Cu-Sn-In ternary alloy matrix was caused by (Cu, In) solid solution formation. The comparisons of mechanical property between several Cu alloys were also investigated for the further mechanical strength improvement.