• Batistão, Bruna Fernanda
• Sergio, T. Amancio-Filho
• Lima, Moyses Leite De
• Pinotti, Vito Eduardo
• Gargarella, P.
• Rodrigues, Ariano De Giovanni

Abstract

Laser Powder Bed Fusion (L-PBF) is an important route for processing aluminum alloys, nevertheless, the high laser reflectivity and thermal conductivity and lower powder flowability of the aluminum alloys remain a challenge for their processing. Aiming to overcome these issues, AA2017 powders were surface-functionalized using chemical etchings. The powders' physical and rheological characterization revealed a decrease in the laser reflectance and an improvement in the flowability of the surface-functionalized powders, when compared to the gas-atomized powder. The higher amount of keyhole porosity in the as-printed L-PBF samples using the surface-functionalized powders also suggests an improvement in the laser absorption of these powders. However, the formation of a thick oxide layer on the surface-functionalized powders led to oxidation porosity in the as-printed samples. Therefore, the chemical etching should be improved to avoid the formation of a thick oxide layer on the powder surface and oxidation porosity in the as-printed L-PBF samples.

Topics

• impedance spectroscopy
• surface
• aluminium
• selective laser melting
• etching
• porosity
• functionalization
• thermal conductivity