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Title: Ideal plasticity and shape memory of nanolamellar high-entropy alloys
Understanding the relationship among elemental compositions, nanolamellar microstructures, and mechanical properties enables the rational design of high-entropy alloys (HEAs). Here, we construct nanolamellar AlxCoCuFeNi HEAs with alternating high– and low–Al concentration layers and explore their mechanical properties using a combination of molecular dynamic simulation and density functional theory calculation. Our results show that the HEAs with nanolamellar structures exhibit ideal plastic behavior during uniaxial tensile loading, a feature not observed in homogeneous HEAs. This remarkable ideal plasticity is attributed to the unique deformation mechanisms of phase transformation coupled with dislocation nucleation and propagation in the high–Al concentration layers and the confinement and slip-blocking effect of the low–Al concentration layers. Unexpectedly, this ideal plasticity is fully reversible upon unloading, leading to a remarkable shape memory effect. Our work highlights the importance of nanolamellar structures in controlling the mechanical and functional properties of HEAs and presents a fascinating route for the design of HEAs for both functional and structural applications.  more » « less
Award ID(s):
2226508 1809640
PAR ID:
10475577
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
AMER ASSOC ADVANCEMENT SCIENCE1200 NEW YORK AVE, NW, WASHINGTON, DC 20005
Date Published:
Journal Name:
Science Advances
Volume:
9
Issue:
41
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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