Designing alloys for additive manufacturing (AM) presents significant opportunities. Still, the
chemical composition and processing conditions required for printability (ie., their suitability for
fabrication via AM) are challenging to explore using solely experimental means. In this work, we
develop a high-throughput (HTP) computational framework to guide the search for highly printable
alloys and appropriate processing parameters. The framework uses material properties from stateof-
the-art databases, processing parameters, and simulated melt pool profiles to predict processinduced
defects, such as lack-of-fusion, keyholing, and balling. We accelerate the printability assessment
using a deep learning surrogate for a thermal model, enabling a 1,000-fold acceleration in
assessing the printability of a given alloy at no loss in accuracy when compared with conventional
physics-based thermal models. We verify and validate the framework by constructing printability
maps for the CoCrFeMnNi Cantor alloy system and comparing our predictions to an exhaustive
’in-house’ database. The framework enables the systematic investigation of the printability of a
wide range of alloys in the broader Co-Cr-Fe-Mn-Ni HEA system. We identified the most promising
alloys that were suitable for high-temperature applications and had the narrowest solidification
ranges, and that was the least susceptible to balling, hot-cracking, and the formation of macroscopic
printing defects. A new metric for the global printability of an alloy is constructed and is further
used for the ranking of candidate alloys. The proposed framework is expected to be integrated
into ICME approaches to accelerate the discovery and optimization of novel high-performance,
printable alloys.
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Corrosion of Additively Manufactured CoCrFeMnNi High Entropy Alloy in Molten NaNO 3 -KNO 3
Exposure testing was performed on CoCrFeMnNi equiatomic high entropy alloy (HEA) produced via directed energy deposition additive manufacturing in NaNO3-KNO3(60–40 wt%) molten salt at 500 °C for 50 h to evaluate the corrosion performance and oxide film chemistry of the HEA. Potentiodynamic electrochemical corrosion testing, scanning electron microscopy, focused ion beam milling coupled with energy dispersive spectroscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and inductively coupled plasma optical emission spectroscopy were used to analyze the corrosion behavior and chemistry of the HEA/nitrate molten salt system. The CoCrFeMnNi HEA exhibited a higher passive current density during potentiodynamic polarization testing than steel alloys SS316L and 4130 and the high-Ni alloy 800 H in identical conditions. The oxide film was primarily composed of a (Mn,Co,Ni)Fe2O4spinel with a vertical plate-like morphology at the surface. Cr and Ni were found to be totally depleted at the outer surface of the oxide and dissolved in high concentrations in the molten salt. While Cr was expected to dissolve into the molten salt, the high concentration of dissolved Ni has not been observed with traditional alloys, suggesting that Ni is less stable in the spinel when Mn and Co are present.
more » « less- NSF-PAR ID:
- 10303509
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- Journal of The Electrochemical Society
- Volume:
- 167
- Issue:
- 8
- ISSN:
- 0013-4651
- Page Range / eLocation ID:
- Article No. 081509
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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