|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Additive Manufacturing Fatigue and Fracture V: Processing-Structure-Property Investigations and Application to Qualification
||Synchrotron Imaging of the Influence of TiB2 in Suppressing Hot Cracking during Laser Powder Bed Fusion of Al-2139
||David T. Rees, Chu Lun Alex Leung, Joe Elambasseril, Sebastian Marussi, Saurabh Shah, Shashidhara Marathe, Milan Brandt, Mark Easton, Peter D. Lee
|On-Site Speaker (Planned)
||David T. Rees
Al-Cu-Mg-Ag alloys are ideally suited for the production of low volume specialist aerospace components by laser powder bed fusion (LPBF). However, the mechanical performance of these alloys is diminished by a high susceptibility to hot cracking, which may reduce fatigue resistance, leading to premature component fracture. We investigated two processing strategies to suppress hot crack formation by controlling the solidification behaviour and resulting microstructure: (1) TiB2 inoculant additions; and (2) in situ optimisation of the LPBF process parameters. Using high-speed synchrotron X-ray imaging, we monitored the LPBF of Al-2139 with and without the addition of TiB2 for a range of parameters. We also performed synchrotron X-ray microtomography (ÁCT) and electron microscopy to characterise build features detrimental to fatigue life, such as porosity, cracking, surface roughness, and microstructural inhomogeneity in terms of population, size, morphology, and location. Our results reveal possible methods to reduce crack formation during LPBF of Al-2139.