|About this Abstract
|2022 TMS Annual Meeting & Exhibition
|Additive Manufacturing of Large-scale Metallic Components
|Prior-β Grain Structure Control of Ti-6Al-4V WAAM in the As-deposited Condition
|James Wainwright, Stewart Williams, Jialuo Ding, Alec Davis
|On-Site Speaker (Planned)
Deposition of Ti-6Al-4V in a plasma wire + arc additive manufacturing process typically produces a prior-β columnar grain structure exhibiting anisotropic mechanical properties. To achieve the formation of equiaxed grain structures which provide isotropic properties requires additional process steps. This research demonstrates a process for controlling the prior-β grain structure in the as-deposited condition through process parameters, removing the need for additional post-processing steps to enable columnar to equiaxed transition. EBSD analysis of deposited Ti-6Al-4V samples illustrates the refinement of the prior-β grain structure when there is a reduction in the specific energy density of material deposited and associated layer height increase. The application of pyrometry to measure the melt pool temperature during deposition identifies a repeatable reduction in the thermal gradient across the melt pool enabling microstructural evolution. Consequently, a solidification map is generated permitting microstructural refinement to be selected in terms of deposition parameters.
|Additive Manufacturing, Titanium, Other