Strength can be controlled by edge dislocations in refractory high-entropy alloys
| Autor: | Jonathan D. Poplawsky, William A. Curtin, Chanho Lee, Yi Chou, Tamás Ungár, Peter K. Liaw, Rui Feng, Michael Widom, Ke An, F Francesco Maresca, Yi-Chia Chou |
|---|---|
| Přispěvatelé: | Computational Mechanical and Materials Engineering |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Multidisciplinary
Materials science Condensed matter physics Science High entropy alloys Alloy deformation Refractory metals General Physics and Astronomy Mechanical properties General Chemistry engineering.material Edge (geometry) Article Mechanical engineering General Biochemistry Genetics and Molecular Biology Condensed Matter::Materials Science Transmission electron microscopy Computational methods crystals engineering High-resolution transmission electron microscopy Refractory (planetary science) |
| Zdroj: | Nature Communications Nature Communications, 12(1):5474. Nature Publishing Group Nature Communications, Vol 12, Iss 1, Pp 1-8 (2021) |
| ISSN: | 2041-1723 |
| Popis: | Energy efficiency is motivating the search for new high-temperature (high-T) metals. Some new body-centered-cubic (BCC) random multicomponent "high-entropy alloys (HEAs)" based on refractory elements (Cr-Mo-Nb-Ta-V-W-Hf-Ti-Zr) possess exceptional strengths at high temperatures but the physical origins of this outstanding behavior are not known. Here we show, using integrated in-situ neutron-diffraction (ND), high-resolution transmission electron microscopy (HRTEM), and recent theory, that the high strength and strength retention of a NbTaTiV alloy and a high-strength/low-density CrMoNbV alloy are attributable to edge dislocations. This finding is surprising because plastic flows in BCC elemental metals and dilute alloys are generally controlled by screw dislocations. We use the insight and theory to perform a computationally-guided search over 10(7) BCC HEAs and identify over 10(6) possible ultra-strong high-T alloy compositions for future exploration. The strength in BCC high-entropy alloys is associated with the type of mobile dislocations. Here the authors demonstrate by means of an ample array of experimental techniques that edge dislocations can control the strength of BCC high-entropy alloys. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink