Abstract
The low laser absorptivity and high thermal conductivity of Al are the foremost concerns when developing Al matrix composites (AMCs) through laser powder bed fusion (L-PBF) process. In this study, we demonstrated an example of improving the 3D-printability of AMCs by means of powder surface modification. Flexible graphene oxide (GO) sheets were carefully coated onto the surface of AlSi10Mg powders under electrostatic self-assembly via a hetero-agglomeration process. In addition to maintaining a shape and particle size similar to the initial metallic powders, the GO-coated AlSi10Mg powders exhibited enhanced laser absorptivity and decreased thermal conductivity, beneficial to their fusion. Under high-energy irradiation, the GO sheets were partially transformed to Al4C3 nanorods individually distributed in the matrix, while the un-reacted parts floated within molten pools under buoyancy, forming an in-situ carbon layer tightly deposited on the surface of the composite build. This work may provide significant guidance for the design and production of high-performance AMCs with advanced architectures for practical applications.
Original language | English |
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Article number | 110678 |
Journal | Materials Characterization |
Volume | 170 |
DOIs | |
Publication status | Published - 2020 Dec |
Keywords
- Graphene
- Laser powder bed fusion (L-PBF)
- Metal matrix composites (MMCs)
- Microstructural evolution
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering