Texture and temperature dependence on the mechanical characteristics of copper electrodeposits

The relationships between grain morphology, preferred orientation, and mechanical performance of commercial grade electrodeposited Cu foils (VLP, MP and HTE) were clarified in this study. Electro-deposited Cu foils showing (220) and (111) growth textures had fine grains of which the distribution was fan-shaped or well-aligned along the through-thickness direction respectively. On the other hand, the (200)-oriented Cu foils consisted of randomly grown coarse grains. Electron backscatter diffraction (EBSD) analysis of the cross-sectioned foils revealed that all the samples exhibited diffuse in-plane texture (on the plane of the foils). The growth texture of the Cu grains dominated Young's modulus of the foils measured by nanoindentation along the through-thickness direction of the Cu foils, in decreasing order was (111), (220) and then (200) oriented foils. With respect to tensile properties, the effect of grain size was more pronounced for tensile strength. The (220)-oriented Cu foils possessed a superior combination of tensile strength and ductility. However, the (200)-oriented foils exhibited a poorer deformation resistance but a lower strength loss at elevated temperatures. Serration in the tensile stress-strain curves could be observed at 150 °C and became intense at 250 °C. In addition to dynamic strain aging, low temperature dynamic recrystallization also accounted for this instability in flow stress.