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arXiv · 1710.11525

Formation of Nb-rich droplets in laser deposited Ni-matrix microstructures

Supriyo Ghosh·Mark R. Stoudt·Lyle E. Levine·Jonathan E. Guyer
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Abstract

Ni-rich $γ$ cells and Nb-rich eutectic droplets that form during laser power bed fusion solidification of Ni-Nb alloys are studied using experiments and simulations. Finite element simulations estimate the cooling rates in the melt pool and phase-field simulations predict the resulting cellular microstructures. The cell and droplet spacings are determined as a function of cooling rate and fit to a power law. The formation of Laves phase is predicted for a critical composition of Nb in the liquid droplets. Finally, our simulations demonstrate that anisotropy in the $γ$ orientation influences the Laves fraction significantly.

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Supriyo Ghosh, Mark R. Stoudt, Lyle E. Levine, Jonathan E. Guyer. 2017-11-20. Formation of Nb-rich droplets in laser deposited Ni-matrix microstructures. https://doi.org/10.1016/j.scriptamat.2017.10.034

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