Effect of Heat Treatment on Microstructure and Tensile Property of Laser-Powder-Bed-Melted Al–Mn–Mg–Sc–Zr Alloy
This study explored the effects of T5 and T6 heat treatments on the microstructure and tensile properties of a laser powder bed fusion (LPBF)-fabricated Al-Mn-Mg-Sc-Zr alloy. The as-built condition exhibited a bi-modal grain structure of equiaxed and columnar grains. Specimens after T5 heat treatment also had a bi-modal microstructure with slight grain growth and the precipitation of secondary Al<sub>3</sub>Sc, which enhanced the yield strength via precipitation hardening but reduced ductility. In contrast, T6 treatment triggered recrystallization, and the microstructure was only coarse equiaxed α-Al grains. This microstructure change was accompanied by coarsened primary Al<sub>3</sub>X and Al<sub>6</sub>(Mn, Fe) precipitates, partial Mg<sub>2</sub>Si dissolution, and significant secondary Al<sub>3</sub>Sc particle growth. Consequently, T6-treated specimens showed lower strength than their T5 counterparts and the poorest ductility due to brittle fracture induced by the stress concentration effect of coarse precipitates at grain boundaries.
Authors
- Hao Zhang (ORCID: https://orcid.org/0000-0003-4080-3222)
- Hui Yin (ORCID: https://orcid.org/0000-0003-3060-7025)
- Sheng Cao (ORCID: https://orcid.org/0000-0003-0036-646X)
- Jinhua Jiang (ORCID: https://orcid.org/0000-0001-8848-0990)
- Mingliang Cui
- Zhiqiang Cao (ORCID: https://orcid.org/0000-0003-1801-3363)
Institutions
- University of Shanghai for Science and Technology (CN)
- Jinan University (CN)
- Beijing University of Technology (CN)
- China State Shipbuilding (China) (CN)
Publication Details
- Journal
- Materials
- Published
- 2025-04-03
- DOI
- https://doi.org/10.3390/ma18071638
- Citations
- 1
- Primary Topic
- Additive Manufacturing Materials and Processes
- Type
- article
- Field-Weighted Citation Impact
- 0.71
Funders
- National Natural Science Foundation of China