Influence of pre-recovery on recrystallization behavior, microstructure and mechanical properties of twin-roll cast AA6016 sheet

Publication date: Available online 14 July 2019Source: Materials Science and Engineering: AAuthor(s): Xianwei Ren, Yuanchun Huang, Wenlong Zhou, Likai Zhao, Qiang Wang, Xudong MinAbstractPre-recovery (PR) treatment and the subsequent recrystallization of twin-roll cast (TRC) AA6016 (Al-1.04Si-0.5Mg-0.4Fe-0.16Mn) sheet are performed. The effects of PR on the recrystallization behavior, grain structure and mechanical properties are investigated. Results reveal that the refinement and homogeneity of the recrystallization grain structure first increase and then decrease when the PR temperature (PRT) is increased. This attributes to the fact that the PR enhances the sub-grain coalescence nucleation (SGCN) when PRT reaches 160 °C. As the PRT exceeds 160 °C, the SGCN is prevented by the concurrent precipitation, and the number of nuclei decreases, resulting in a coarse and inhomogeneous grain structure. Additionally, mechanical anisotropy (Δr) of the sheet is weakened by the PR. In particular, the Δr after PR treatment at 160 °C is 0.01, which is significantly smaller than that of the sheet without PR treatment (0.26). The microstructural refinement and high grain structure homogeneity improve the mechanical properties of the TRC AA6016 sheet.
Source: Materials Science and Engineering: A - Category: Materials Science Source Type: research