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.