First-Principles Study on Structure and Stability of GP Zones in Al-Mg-Si(-Cu) Alloy.

ABSTRACT: Nanostructured Guinier-Preston (GP) zones are critical for the strength of Al-Mg-Si(-Cu) aluminum alloys. However, there are controversial reports about the structure and growth mechanism of GP zones. In this study, we construct several atomic configurations of GP zones according to the previous research. Then first-principles calculations based on density functional theory were used to investigate the relatively stable atomic structure and GP-zones growth mechanism. The results show that on the (100) plane, GP zones consist of {MgSi} atomic layers without Al atoms, and the size tends to grow up to 2 nm. Along the (100) growth direction, even numbers of {MgSi} atomic layers are more energetically favorable and there exist Al atomic layers to relieve the lattice strain. {MgSi}₂Al

SUBMITTER: Su Y 

PROVIDER: S-EPMC10254046 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature