Abstract
Lightweighting of structural materials has proven indispensable in the energy economy, predicated on alloy design with high strength-to-weight ratios. Modern aluminum alloys have made great strides in ambient temperature performance and are amenable to advanced manufacturing routes such as additive manufacturing, but lack elevated temperature robustness where gains in efficiency can be obtained. Here, we demonstrate the intentional design of disorder at interfaces, a notion generally associated with thermal runaway in traditional materials, in a segregation-engineered ternary nanocrystalline Al–Ni–Ce alloy that exhibits exceptional thermal stability and elevated temperature strength. In-situ transmission electron microscopy in concert with ultrafast calorimetry and X-ray total scattering point to synergistic co-segregation of Ce and Ni driving the evolution of amorphous intergranular films separating sub- 10 nm Al-rich grains, which gives rise to emergent thermal stability. We ascribe this intriguing behavior to near-equilibrium interface conditions followed by kinetically sluggish intermetallic precipitation in the confined disordered region. The resulting outstanding mechanical performance at high homologous temperatures lends credence to the efficacy of promoting disorder in alloy design and discovery.
Originalsprache | Englisch |
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Aufsatznummer | 116973 |
Seitenumfang | 14 |
Fachzeitschrift | Acta Materialia |
Jahrgang | 215.2021 |
Ausgabenummer | 15 August |
Frühes Online-Datum | 8 Mai 2021 |
DOIs | |
Publikationsstatus | Veröffentlicht - 15 Aug. 2021 |
Bibliographische Notiz
Funding Information:This material is based upon work supported by the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) under the Advanced Manufacturing Office Award number DE-EE0009114 . GHB acknowledges support from the National Science Foundation Graduate Research Fellowship under Grant no. 1650114 . DK gratefully acknowledges funding from the European Research Council under grant agreement no. 771146 (TOUGHIT). DJS and JRT acknowledge support by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award no. DE-SC0021060. TJR acknowledges support by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award no. DE-SC0021224. This research used beamline 28-ID-1 of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract no. DE-SC0012704. The MRL Shared Experimental Facilities are supported by the MRSEC Program of the NSF under Award no. DMR 1720256; a member of the NSF-funded Materials Research Facilities Network ( http://www.mrfn.org ).
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