Freeman, F.S.H.B. orcid.org/0000-0002-7402-1790, Thomas, B., Chechik, L. et al. (1 more author) (2022) Multi-faceted monitoring of powder flow rate variability in directed energy deposition. Additive Manufacturing Letters, 2. 100024. ISSN 2772-3690
Abstract
Powder flow rate is a key parameter in Directed Energy Deposition (DED) processes. During a typical build, if powder flow rate is reduced for just 1 second, 30 mm of melt track is affected. Consequently, even a small variation in powder flow rate can have significant implications on build quality. In this work, the powder flow stability for different types of 316 L steel powders was quantified using a combination of methodologies including offline weight measurements, flow imaging, in-situ build data and coaxial melt pool imaging. Flow rate oscillation was observed, correlated with the periodicity of powder hopper turntable rotation, at sufficient magnitude to cause build quality effects and be identifiable in coaxial melt pool imaging. The implications of flow rate variation on the use of melt pool imaging for closed-loop control are discussed.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). |
Keywords: | Directed energy deposition; Powder flow rate; Powder flow imaging; Melt pool imaging |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Materials Science and Engineering (Sheffield) |
Funding Information: | Funder Grant number Engineering and Physical Sciences Research Council EP/P006566/1 European Commission - HORIZON 2020 820776 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 05 Jan 2022 09:13 |
Last Modified: | 05 Jan 2022 09:13 |
Status: | Published |
Publisher: | Elsevier BV |
Refereed: | Yes |
Identification Number: | 10.1016/j.addlet.2021.100024 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:181921 |