Texture and Plastic Anisotropy in Model Aluminium - Lithium Alloys

Abstract

The specific roles of Li, Zr and Cu alloying elements in Al-Li alloys have been investigated in terms of their influence on texture evolution during rolling and subsequent plastic anisotropy. Three model alloys; Al-2.3% Li, Al-2.3% Li-0.1% Zr and Al-2.3% Li-1.2% Cu-0.1% Zr were hot and cold rolled to reductions up to 92% and their texture evolution systematically characterised by X-ray pole figures and complete ODFs. Hot rolling of the Zr containing alloys, which do not recrystallize, led to a strong Bs texture component. Cold rolling of all alloys gave the usual Taylor-type β fibre components, with certain variations according to the precipitation state which can favour or inhibit shear banding.Pronounced plastic anisotropies, R(α), were measured on the rolled sheets with R_min at α = 0° and R_max at α ≈ 60°. Actual values depend upon rolling temperature and strain but typically R_min ≈ 0.3 and R_max ≈ 1.5 to 2. The quantitative texture data was used together with the CMTP and Taylor models to predict the anisotropy; in general the CMTP model gave a reasonable correlation with the experimental values.