Achieving highly strengthened Al–Cu–Mg alloy by grain refinement and grain boundary segregation

Takahiro Masuda (1) , Xavier Sauvage (2) , Shoichi Hirosawa (1) , Zenji Horita (3)

1 Yokohama National University
2 GPM - Groupe de physique des matériaux
3 Department of Material Science and Engineering [Fukuoka]

An age-hardenable Al-Cu-Mg alloy (A2024) was processed by high-pressure torsion (HPT) for producing an ultrafine-grained structure. The alloy was further aged for extra strengthening. The tensile strength then reached a value as high as ~1 GPa. The microstructures were analyzed by transmission electron microscopy and atom probe tomography. The mechanism for the high strength was clarified in terms of solid-solution hardening, cluster hardening, work hardening, dispersion hardening and grain boundary hardening. It is shown that the segregation of solute atoms at grain boundaries including subgrain boundaries plays a significant role for the enhancement of the tensile strength.

Keywords: aluminum alloys; severe plastic deformation; grain refinement; high strength; grain boundary segregation 2

Domains: Physics [physics]; Condensed Matter [cond-mat]; Materials Science [cond-mat.mtrl-sci]

Takahiro Masuda, Xavier Sauvage, Shoichi Hirosawa, Zenji Horita. Achieving highly strengthened Al–Cu–Mg alloy by grain refinement and grain boundary segregation. Materials Science and Engineering: A, 2020, 793, pp.139668. ⟨10.1016/j.msea.2020.139668⟩. ⟨hal-02899710⟩