Effect of cold rolling pre-deformation on microstructure and properties of V-1469 Al-Li alloy

In order to provide a detailed reference for the processing of high-performance Al-Li alloy, the effects of cold rolling pre-deformation on the microstructure and properties of V-1469 Al-Li alloy were investigated by Vickers hardness, tensile measurement, intergranular corrosion, electrochemical technique and electron microscopy. The results show that the mechanical properties of V-1469 Al-Li alloy can be improved by cold rolling pre-deformation treatment. When a 10% deformation was applied, the tensile strength and yield strength reached 600 MPa and 560 MPa, respectively, and the elongation remained above 7%. Moreover, cold rolling pre-deformation treatment can effectively improve the corrosion properties of V-1469 Al-Li alloy. With the increase of pre-deformation, the maximum corrosion depth and corrosion degree are decreased. In addition, with the increase of cold rolling pre-deformation, the microstructure observation shows that the precipitation of theta' (Al2Cu) phase is inhibited, while the main hardening-phase of T1 (Al2CuLi) phase disperses homogeneously in the grain. Besides, the volume fraction of T1 phases on the stacking fault (grain boundary and sub-grain boundary) decreases and its precipitating pattern changes from continuous precipitation to discontinuous precipitation, which causes the width of the precipitate free zone (PFZ) to gradually decrease. 2020 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).