| Autor: |
Eric Gärtner, Arne Witte, Nicolas J. Peter, Vivek Devulapalli, Nils Ellendt, Gerhard Dehm, Eric A. Jägle, Volker Uhlenwinkel, Lutz Mädler |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
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| Zdroj: |
Materials & Design, Vol 226, Iss , Pp 111626- (2023) |
| Druh dokumentu: |
article |
| ISSN: |
0264-1275 |
| DOI: |
10.1016/j.matdes.2023.111626 |
| Popis: |
Metal powders in laser-powder-bed-fusion (L-PBF) often exhibit cohesive flow resulting from interparticle adhesion. Nanoparticle dry-coating can improve powder flowability and promote powder layer densification. A Co25Cr25Fe25Ni25 metal powder (20–90 µm) is dry-coated with TiN particles with a diameter of 16 nm at low concentrations of up to 69 ppm. The dynamic angle of repose decreased and bulk powder density increased compared to the uncoated state from 49 ° and 4.67 g/cm3 to 29 ° and 4.81 g/cm3 with dry-coating of TiN, respectively. UV/Vis spectroscopy showed negligible alterations by TiN additions on the powder light absorption. The powder modifications strongly affected their corresponding processability in L-PBF and reduced the melt pool signatures of the in situ detected confocal single-color pyrometer signal as well as ex situ measured melt pool depth and width. With increasing flowability, a significant decrease in thermal emission and melt pool size was observed. The results demonstrate the impact of powder flowability and bulk powder density on the quality of L-PBF parts when particle interactions are actively modified. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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Full Text from ScienceDirect