Deformation behavior of pure Cu and Cu-Ni-Si alloy evaluated by micro-tensile testing

Abstract

Micro-tensile tests of pure copper and a precipitation strengthening-type Cu alloy, Cu-Ni-Si alloy, were performed using micro-sized tensile specimens with 10 × 10 μm2 in cross-section and 40 μm in length and a micro-gripper, which were fabricated by a focused ion beam system. The obtained experimental results were compared with the results of Cu-Ni-Si alloy bulk sample. The micro-tensile tests of both pure Cu and Cu-Ni-Si alloy showed the typical serrations caused by moving of dislocations and a decrease of flow stress by the necking. In the Cu-Ni-Si alloy, characteristic deformation of work-hardening was observed. Electron back scatter diffraction analysis showed a gradual change in crystal orientation at the necking area.