Investigation of temperature distribution and solidification morphology in multilayered directed energy deposition of Al-0.5Sc-0.5Si alloy

• Published in: International journal of heat and mass transfer 2022-05, Vol.186, p.122492, Article 122492
• Main Authors: Singh, Amit Kumar, Mundada, Yasham, Bajaj, Priyanshu, Wilms, Markus B., Patil, Jeet P, Mishra, Sushil Kumar, Jägle, Eric A., Arora, Amit
• Format: Article
• Language: English
• Subjects: Aluminum base alloys; Aluminum scandium alloy; Computation; Deposition; Laser beams; Metal additive manufacturing; Morphology; Numerical modeling; Process parameters; Solidification; Solidification morphology; Temperature distribution; Temperature gradients
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2021.122492

•A coupled heat transfer fluid flow and solidification model for the L-DED processed al-0.5Sc-0.5Si alloy.•Thermal cycle, melt pool size, and solidification parameters are studied for varying process parameters.•Mixed equiaxed and columnar structures are predicted inside the melt pool.•Epitaxial growth in longitudinal cross-section shows remelting and solidification for multilayer deposition. The temperature distribution, geometry and size of the melt pool, and solidification parameters were computed using the heat transfer and material flow model for the directed energy deposition process. The thermal cycle and melt pool size were computed for different process parameters such as laser power, deposition speed, and laser beam radius across the multiple layers for deposition of Al-0.5Sc-0.5Si alloy. The computed thermal cycles at various locations from the centerline and melt pool size showed fair agreement with the experimentally measured result. The computed thermal gradient and solidification rate were mapped over the solidification map, which was in agreement with the experimentally observed microstructure. The transition in solidification morphology with varying melt pool depth and process parameters were fairly observed inside the melt pool. The fraction of equiaxed solidification morphology increases with the reduction in a thermal gradient. [Display omitted] .