High-temperature mechanical properties of γ/γ′ Co-Ni-W-Al superalloy microlattices

SCRIPTA MATERIALIA

卷:188

Article

Park, Hyeji^1,2  Li, Chunan²  Jakus, Adam E.²  Shah, Ramille N.^2,3  Choe, Heeman¹  Dunand, David C.² 

[1] Kookmin Univ, Sch Mat Sci & Engn, 77 Jeongneung Ro, Seoul, South Korea

[2] Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA

[3] Northwestern Univ, Dept Biomed Engn, Simpson Querrey Inst BioNanotechnol, Chicago, IL 60611 USA

关键词: Co-based superalloy;    Microlattice architecture;    3D-printing;    Mechanical property;    High-temperature characterization;   

DOI  :  10.1016/j.scriptamat.2020.07.009

来源: Elsevier

【 摘 要 】

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) H-2 -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 m diameter struts, display a peak in yield strength at 750 degrees C, consistent with their gamma/gamma' 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 degrees C, which nevertheless remains similar to Ni-based superalloy foam, with 35% relative density. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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