Abstract
Abstract: Additive manufacturing is a promising alternative method for fabricating components of Ni-based superalloys which are difficult to cast, form and join. However, typical thermal cycles associated with laser powder bed-fusion techniques suppress the formation of desirable microstructures containing γ′ particles, necessitating long-time post-process heat treatments. Here we report in-situ precipitation of γ′ (L12-ordered) particles and carbides during electron-beam powder bed-fusion of Inconel-738. The γ′ particles are homogenously distributed across the build and exhibit a multimodal size distribution. Based on atom-probe microscopy, we propose a eutectic reaction and multiple nucleation, growth, coarsening and dissolution bursts during thermal cycling as formation mechanism.
| Original language | English |
|---|---|
| Pages (from-to) | 13342-13350 |
| Number of pages | 9 |
| Journal | Journal of Materials Science |
| Volume | 55 |
| Issue number | 27 |
| DOIs | |
| State | Published - Sep 1 2020 |
| Externally published | Yes |
Funding
Funding by the AUSMURI program, Department of Industry, Innovation and Science, Australia is acknowledged. Sample was kindly provided by Miss Sabina Kumar, The University of Tennessee, Knoxville. A/Prof. Sophie Primig is supported under the Australian Research Council’s DECRA (project number DE180100440) and the UNSW Scientia Fellowship schemes. The authors acknowledge the technical assistance and use of facilities supported by Microscopy Australia at the Electron Microscope Unit at the Mark Wainwright Analytical Centre at UNSW and Sydney Microscopy & Microanalysis at the University of Sydney. The research at The University of Tennessee, Knoxville is partly sponsored by the ONR award number N00014-18–1-2794. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the ONR. Part of the research at Oak-Ridge National Lab was supported by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office, under contract DE-AC05-00OR22725 with UT-Battelle, LLC. Funding by the AUSMURI program, Department of Industry, Innovation and Science, Australia is acknowledged. Sample was kindly provided by Miss Sabina Kumar, The University of Tennessee, Knoxville. A/Prof. Sophie Primig is supported under the Australian Research Council’s DECRA (project number DE180100440) and the UNSW Scientia Fellowship schemes. The authors acknowledge the technical assistance and use of facilities supported by Microscopy Australia at the Electron Microscope Unit at the Mark Wainwright Analytical Centre at UNSW and Sydney Microscopy & Microanalysis at the University of Sydney. The research at The University of Tennessee, Knoxville is partly sponsored by the ONR award number N00014-18–1-2794. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the ONR. Part of the research at Oak-Ridge National Lab was supported by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office, under contract DE-AC05-00OR22725 with UT-Battelle, LLC.
| Funders | Funder number |
|---|---|
| Office of Naval Research | N00014-18–1-2794 |
| U.S. Department of Energy | |
| Advanced Manufacturing Office | DE-AC05-00OR22725 |
| Office of Energy Efficiency and Renewable Energy | |
| University of Tennessee | |
| Australian Research Council | DE180100440 |
| University of New South Wales | |
| University of Sydney | |
| Department of Industry, Innovation and Science, Australian Government |
