About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
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Symposium
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Additive Manufacturing: Length-Scale Phenomena in Mechanical Response
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Presentation Title |
Microstructural Control and Variant Selection in Laser Powder Bed Fusion of Ti-6Al-4V |
Author(s) |
Dina Fouad, Yu-Lung Chiu, Moataz M. Attallah |
On-Site Speaker (Planned) |
Dina Fouad |
Abstract Scope |
Microstructural control during Laser Powder Bed Fusion (L-PBF) of α+ β Ti-alloys is rather complex. The as-solidified microstructure experiences sophisticated phase transformations (e.g. β → α' transformation and β-grain growth during melt pool remelting), which ultimately determine the final properties, either in the as-fabricated or post-process heat treated conditions. In this study, we explore the mechanisms of microstructural development during L-PBF, particularly the prior β-grain size and texture. With an aim to achieve isotropic mechanical behaviour, in-situ microstructure control was achieved by varying heat input (energy density) and distribution (scanning strategies) as means of controlling thermal gradients. Cooling rates were estimated using melt pool simulations. Electron backscattered diffraction (EBSD) was used to study the texture development. Reconstructed EBSD micrographs confirmed the presence of β grain boundary α variant selection with varying intensities as a function of L-PBF parameters. Tensile testing was conducted using Digital Image Correlation to assess the mechanical performance and the utility of microstructural control in creating hybrid functionally-graded microstructures. |
Proceedings Inclusion? |
Planned: |