Influence of Intrinsic Heat Treatment (IHT) on Precipitation Kinetics during Laser Beam Powder Bed Fusion of Al-Mg-Sc Alloy

Abstract:

Laser Beam Powder Bed Fusion (LBPBF) process has a unique feature termed as IntrinsicHeat Treatment (IHT), where solidified layers undergo series of heating and cooling (during thesubsequent building of a part). Thus, the LBPBF process offers the opportunity for the formation of microstructuralfeatures, which can have the potential to transform the mechanical properties of the part.In the case of AlMgSc alloy, L12 phase Al3Sc precipitates are thermodynamically favored to nucleatein the Al matrix due to coherency. After post-process analysis, it is evident that Al3Sc precipitatesformed during the LBPBF process, but it is unlikely to monitor (in-situ) the kinetics of precipitation.Therefore, based on inputs from the thermal model, the simulation of precipitation kinetics during theLBPBF process (IHT) is performed. The rapid heating and cooling cause the formation of new vacancies,where Al3Sc precipitates can nucleate and grow. The KWN model based on solid-state phasetransformation is used for modeling of precipitation kinetics. The thermal data at two locations in apart is collected and used to determine the average radius, number density, and volume fraction ofprecipitates. It is found that the IHT does not influence precipitation kinetics, and has no potential toalter the spatial properties of the part.

• Periodical: Advanced Materials Research (Volume 1161)
• Pages: 47-55
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1161.47
• Online since: March 2021
• Authors: Yuvaraj Ganpati Patil*, Loreen Mertens, Andre Dröse, Vasily Ploshikhin
• Keywords: Intrinsic Heat Treatment, Laser Beam Powder Bed Fusion, Precipitation Kinetics

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