About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
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Symposium
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High Entropy Materials: Concentrated Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond IV
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Presentation Title |
Multi-scale Characterization of 3D Printable CrCoNi-based ODS-MPEA Designed for High-temperatures and Extreme Environments |
Author(s) |
Milan Heczko, Timothy M Smith, Christopher A. Kantzos, Veronika Mazanova, Antonin Dlouhy, Michael J. Mills |
On-Site Speaker (Planned) |
Milan Heczko |
Abstract Scope |
Our recent work (Nature, 2023) has demonstrated a new strategy to design alloys for high-temperature applications using additive manufacturing. Combined with multi-principal element alloy (MPEA) and oxide-dispersion-strengthening (ODS) concepts it opens up a vast unexplored compositional space to develop new 3D printable alloys. Here, we reveal microstructural origins of extraordinary performance of these new alloys by multi-scale characterization approach. Probe-corrected atomic resolution and diffraction contrast imaging (DCI) in STEM is combined to analyze defect microstructure consisting of network of 1/2<110> dislocations dissociated into distinct intrinsic stacking faults bound by 1/6<112> Shockley partials, as well as numerous extended stacking-fault node configurations and stacking-fault tetrahedra. Nano-oxide dispersion, its spatial distribution and interaction with defect microstructure is characterized by cross-correlation of tilting experiments, the 3D stereo DCI microscopy and Super-X energy dispersive X-ray spectroscopy in STEM. Critical aspects determining performance of 3D printable ODS-MPEAs are systematically identified and discussed. |