Laser‐Powder Melt Pool Solidification Dynamics and Microstructural Engineering of Ti‐5553 Microlattices

Andrews, Caleb E. [Johns Hopkins Univ., Baltimore, MD (United States)] (ORCID:0000000269347665); Martin, Aiden A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Strantza, Maria [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Forien, Jean‐Baptiste [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Vrancken, Bey [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; DePond, Philip [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Calta, Nicholas P. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Nicolino, Jenny Wang [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Matthews, Manyalibo J. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Taheri, Mitra L. [Johns Hopkins Univ., Baltimore, MD (United States)]

doi:10.1002/adem.202403070

DOE OSTI · 3000179

Laser‐Powder Melt Pool Solidification Dynamics and Microstructural Engineering of Ti‐5553 Microlattices

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Abstract

The fine geometric and topological control afforded by additive manufacturing technologies has enabled the manufacture of architected materials across length scales, and enabling tunable mechanical performance as a function of local and global design. Progress has been made to tune the mechanical response of architected materials through geometry, but understanding how the geometry and processing conditions will inform the microstructure remains a challenge due to the rapid solidification in laser powder bed fusion. This study uses in situ X-ray imaging and electron backscatter diffraction microscopy to demonstrate that the melt pool size, microstructure morphology, and elastic strain distribution is influenced by a combination of lattice geometry and laser processing conditions. These results indicate that within larger melt pools the local thermal gradients are sufficient to enable a columnar-to-equiaxed transition across the melt pool. Furthermore, the solidification mechanisms producing these microstructures are examined across the first 5 ms of melting and solidification, described via in situ high-speed X-ray imaging and mirrored via multiphysics simulation.

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additive manufacturing in situ melt pool measurement laser powder bed fusion microlattice materials microstructural engineering

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Andrews, Caleb E. [Johns Hopkins Univ., Baltimore, MD (United States)] (ORCID:0000000269347665), Martin, Aiden A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Strantza, Maria [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Forien, Jean‐Baptiste [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Vrancken, Bey [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], DePond, Philip [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Calta, Nicholas P. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Nicolino, Jenny Wang [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Matthews, Manyalibo J. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Taheri, Mitra L. [Johns Hopkins Univ., Baltimore, MD (United States)]. 2025-09-18. Laser‐Powder Melt Pool Solidification Dynamics and Microstructural Engineering of Ti‐5553 Microlattices. https://doi.org/10.1002/adem.202403070

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