Effects of precipitates and texture on the anisotropy of high-strength Cu-Ni-Si alloy sheets

The effects of texture and precipitates on the plane anisotropy of Cu-Ni-Si alloy under different solid-solution temperature conditions were investigated by X-ray diffraction, electron backscattered diffraction, and transmission electron microscopy. The results show that strength and elongation first increase and then decrease with increasing solid-solution temperature, exhibiting apparently anisotropy. After 800℃ solid solution, the Cu' and S' are mainly texture and the alloy has weak anisotropic properties, which correlates with the coexistence of Brass, Goss, and {011}〈511〉orientation owing to deformed grains. Complete recrystallization can be obtained at high temperature solution (≥ 850℃), the Cu' and S' texture intensity increases, whereas the Brass texture weakens and disappears and the anisotropy increases. δ-Ni₂Si precipitation is observed after 850℃ solution and subsequent aging, and the crystal orientation between the matrix and precipitates is [001]_Cu//[110]_δ and (010)_Cu//(001)_δ. The fraction of nanosize precipitates decreases significantly with increasing temperature and this improves the anisotropy.