Abstract
This study investigates the influence of different scanning strategies on the hardness of the parts, fabricated by direct metal laser melting . In this work, pre-alloyed powder of titanium alloy (Ti–6Al–4V) is used to produce dense parts with three different scanning strategies: unidirectional, alternate, and cross-hatching. A numerical scheme is developed to predict the heat transfer , fluid flow, and thermal history -based phase transformation during the process. Surface hardness is calculated from the obtained phase fractions. Hardness is measured experimentally, and X-ray diffraction is used for phase identification. The hardness is found to be highly dependent on the microstructure of as-built parts. The results show that rapid solidification during direct metal laser melting leads to the formation of hcp-structured acicular martensite from the parent beta phase, which increases the hardness . Higher part densities are observed for cross-hatching strategy compared to other scanning strategies. The predicted maximum hardness for different scanning strategies compare well against the experimental observations.
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Ghate, N.D., Gaur, B., Shrivastava, A. (2020). Effect of Scanning Strategy on Additively Manufactured Ti6Al4V. In: TMS 2020 149th Annual Meeting & Exhibition Supplemental Proceedings. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-030-36296-6_33
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DOI: https://doi.org/10.1007/978-3-030-36296-6_33
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