Abstract
Cobalt-based superalloy microlattices were created via (i) three-dimensional-extrusion printing of inks containing a suspension of Co-, Ni- and W-oxide particles, (ii) H2-reduction of the oxides and sintering to a homogenous Co-Ni-W alloy, (iii) Al pack-cementation to deposit Al on the microlattice struts, followed by Al-homogenization. The resulting Co-(18–20)Ni-(5–6)W-(10–13)Al (at.%) microlattices, with 27–30% relative density and 350 μm diameter struts, display a peak in yield strength at 750 °C, consistent with their γ/γ′ aged microstructure. Oxidation resistance is strongly improved compared to Al-free printed Co-Ni-W lattices, via the formation of an Al2O3 surface layer. However, the resulting Al depletion within the struts reduces creep resistance at 850 °C, which nevertheless remains similar to Ni-based superalloy foam, with 35% relative density.
Original language | English (US) |
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Pages (from-to) | 146-150 |
Number of pages | 5 |
Journal | Scripta Materialia |
Volume | 188 |
DOIs | |
State | Published - Nov 2020 |
Keywords
- 3D-printing
- Co-based superalloy
- High-temperature characterization
- Mechanical property
- Microlattice architecture
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys