These results suggest that significant improvements in FCC MPEA systems can still be realized through additional alloying. 29 found that three atomic percentage (at.%) additions of W in NiCoCr created a finer grain structure (average grain size 1 μm), resulting in a large increase in yield strength of the alloy (over 1,000 MPa, compared with 500 MPa for nonalloyed NiCoCr) while maintaining exceptional ductility of over 50% (ref. Recent studies have also found that the addition of carbon to MPEAs resulted in improved strength 26, 27, 28. found that doping the high-entropy alloy, NiCoCrFeMn, with 30 ppm of boron resulted in significant improvements in strength and ductility attributed to both grain boundary and interstitial strengthening from the boron 25. Alloying and doping of NiCoCr with refractory elements and interstitials have also been explored recently. These properties are also attributed to strain-induced, face-centred cubic (FCC) to hexagonal close-packed (HCP) phase transformations and local stacking-fault variations. Recently, this alloy was shown to provide impressive tensile properties (1,100 MPa room temperature yield strength) when undergoing partial recrystallization heat treatment after cold rolling 17. This alloy family provides the highest strength at room temperature among the Cantor alloy and its derivatives 2, 24. One Cantor alloy derivative of special interest is the medium-entropy alloy NiCoCr. As a result, these alloys show great potential for numerous aerospace and energy applications in elevated-temperature and corrosive environments, allowing for weight reduction and higher performance operation. This class of alloys has also proven to be robust, resisting hydrogen environment embrittlement 21, exhibiting improved irradiation properties 22 and providing superior strength at cryogenic temperatures 23. Overcoming the strength–ductility trade-off is a result of atomic-scale deformation mechanisms 16, such as locally variable stacking-fault energies 19 and magnetically driven phase transformations 20. This group of alloys showed excellent strain hardening, resulting in high tensile strength and ductility 7, 15, 16, 17, 18. One of the most heavily investigated MPEA family is the Cantor alloy CoCrFeMnNi and its derivatives 2, 8, 14. In the past decade numerous scientific investigations have uncovered remarkable properties exhibited by these alloys 7, 10, 11, 12, 13. High-entropy alloys, also commonly referred to as multi-principal element alloys (MPEAs), are a class of materials that are currently of interest among the metallurgical community 1, 2, 7, 8, 9. These results showcase how future alloy development that leverages dispersion strengthening combined with additive manufacturing processing can accelerate the discovery of revolutionary materials. The success of this alloy highlights how model-driven alloy designs can provide superior compositions using far fewer resources compared with the ‘trial-and-error’ methods of the past. The mechanical results of GRX-810 show a twofold improvement in strength, over 1,000-fold better creep performance and twofold improvement in oxidation resistance compared with the traditional polycrystalline wrought Ni-based alloys used extensively in additive manufacturing at 1,093 ☌ 5, 6. We show the successful incorporation and dispersion of nanoscale oxides throughout the GRX-810 build volume via high-resolution characterization of its microstructure. This oxide-dispersion-strengthened alloy, called GRX-810, uses laser powder bed fusion to disperse nanoscale Y 2O 3 particles throughout the microstructure without the use of resource-intensive processing steps such as mechanical or in situ alloying 3, 4. Here we develop a new oxide-dispersion-strengthened NiCoCr-based alloy using a model-driven alloy design approach and laser-based additive manufacturing. Multiprincipal-element alloys are an enabling class of materials owing to their impressive mechanical and oxidation-resistant properties, especially in extreme environments 1, 2.
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