Insights on grain refinement of Al-Mn-Fe-Si alloy via in situ reaction during laser direct energy deposition

Published

February 2, 2025

Author(s)

Qingyu Pan, Fan Zhang, Deepak Vikraman Pillai, Zilong Zhang, Yufeng Zheng, Lang Yuan, Monica Kapoor, John Carsley, Xiaoyuan Lou

Abstract

In the present work, we studied the grain refinement by adding in situ reactants, pure titanium (Ti) or a combination of Ti and boron (B), and investigated the governing mechanism in Al-Mn-Fe-Si 3104 alloy made by laser direct energy deposition (DED) additive manufacturing (AM). The transition from large columnar grains to refined equiaxed grains was achieved by Ti addition or Ti+B additions and in situ reaction during laser AM. The sole addition of Ti was identified as the best grain refiner in this study. The increase in Ti addition from 0.5 to 1 wt% resulted in a transition from partial to complete equiaxed grain structure. With the same amount of Ti, B addition would diminish grain refinement, due to the consumption of Ti to form TiB2. The direct addition of TiB2 particles was proven to be ineffective to grain refinement. Substrate heating further improved grain refinement. The study demonstrated the higher nucleation potency of Al3Ti than in situ formed TiB2 during laser DED AM. The formation of Al3Ti plays the most critical role in grain nucleation.

Citation

Journal of Alloys and Compounds

Volume

1016

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.jallcom.2025.178983

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Keywords

Direct energy deposition additive manufacturing, Al-Mn alloy, Grain refinement, Columnar to equiaxed transition, Synchrotron XRD

Citation

Pan, Q. , Zhang, F. , Vikraman Pillai, D. , Zhang, Z. , Zheng, Y. , Yuan, L. , Kapoor, M. , Carsley, J. and Lou, X. (2025), Insights on grain refinement of Al-Mn-Fe-Si alloy via in situ reaction during laser direct energy deposition, Journal of Alloys and Compounds, [online], https://doi.org/10.1016/j.jallcom.2025.178983, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=958571 (Accessed October 10, 2025)