Modulating precipitation pathways and mechanical properties of Al-Si-Mg alloys via Cu: experimental and simulation study
Abstract
Combining multi-scale simulations and experiments, this work elucidates how Cu (0–4 wt.%) affects the precipitation behavior and mechanical properties of an Al-Si-Mg alloy. Increasing Cu contents drives a sequential evolution of dominant precipitates: β′′ → β′′ + QP → QP → QP + θ′, raising yield strength from 285 MPa to 364 MPa but reduces ductility from 10.1% to 6.8%. Critically, atomistic simulations elucidate the kinetic pathway through which Cu addition suppresses β′′ precipitation and confirm that the dominant interaction between dislocations and the θ′ shifts to Orowan looping. This mechanistic change is identified as the fundamental origin of the observed strength-ductility trade-off. These findings offer a theoretical foundation for the future design of high-performance Al alloys.
Fields of Study & Subjects
Aluminum Alloy Microstructure Properties
Microstructure and mechanical properties
Metal Forming Simulation Techniques
Publication details
- Journal / source
- Materials Research Letters
- Publisher
- Informa UK Limited
- Volume
- 14
- Issue
- 5
- Pages
- 593–602
- Publication date
- 2 March 2026
- Language
- EN