Samenvatting
Surface roughness of laser powder bed fusion (L-PBF) printed overhang regions is a major contributor to deteriorated shape accuracy/surface quality. This study investigates the mechanisms behind the evolution of surface roughness (Ra) in overhang regions. The evolution of surface morphology is the result of a combination of border track contour, powder adhesion, warp deformation, and dross formation, which is strongly related to the overhang angle (θ). When 0° ≤ θ ≤ 15°, the overhang angle does not affect Ra significantly since only a small area of the melt pool boundaries contacts the powder bed resulting in slight powder adhesion. When 15° < θ ≤ 50°, powder adhesion is enhanced by the melt pool sinking and the increased contact area between the melt pool boundary and powder bed. When θ > 50°, large waviness of the overhang contour, adhesion of powder clusters, severe warp deformation and dross formation increase Ra sharply.
Originele taal-2 | English |
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Pagina's (van-tot) | S66-S84 |
Aantal pagina's | 19 |
Tijdschrift | Virtual and Physical Prototyping |
Volume | 16 |
Nummer van het tijdschrift | sup. 1 |
Vroegere onlinedatum | 10-mrt.-2021 |
DOI's | |
Status | Published - 2021 |