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Title: A 3D printable alloy designed for extreme environments
Abstract Multiprincipal-element alloys are an enabling class of materials owing to their impressive mechanical and oxidation-resistant properties, especially in extreme environments1,2. Here we develop a new oxide-dispersion-strengthened NiCoCr-based alloy using a model-driven alloy design approach and laser-based additive manufacturing. This oxide-dispersion-strengthened alloy, called GRX-810, uses laser powder bed fusion to disperse nanoscale Y2O3particles throughout the microstructure without the use of resource-intensive processing steps such as mechanical or in situ alloying3,4. We show the successful incorporation and dispersion of nanoscale oxides throughout the GRX-810 build volume via high-resolution characterization of its microstructure. 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 °C5,6. 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. These results showcase how future alloy development that leverages dispersion strengthening combined with additive manufacturing processing can accelerate the discovery of revolutionary materials.  more » « less
Award ID(s):
2323717
PAR ID:
10543630
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Corporate Creator(s):
Editor(s):
NA
Publisher / Repository:
Nature
Date Published:
Journal Name:
Nature
Volume:
617
Issue:
7961
ISSN:
0028-0836
Page Range / eLocation ID:
513 to 518
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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