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Title: Multiplicity of dislocation pathways in a refractory multiprincipal element alloy

Refractory multiprincipal element alloys (MPEAs) are promising materials to meet the demands of aggressive structural applications, yet require fundamentally different avenues for accommodating plastic deformation in the body-centered cubic (bcc) variants of these alloys. We show a desirable combination of homogeneous plastic deformability and strength in the bcc MPEA MoNbTi, enabled by the rugged atomic environment through which dislocations must navigate. Our observations of dislocation motion and atomistic calculations unveil the unexpected dominance of nonscrew character dislocations and numerous slip planes for dislocation glide. This behavior lends credence to theories that explain the exceptional high temperature strength of similar alloys. Our results advance a defect-aware perspective to alloy design strategies for materials capable of performance across the temperature spectrum.

 
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Award ID(s):
1725797
NSF-PAR ID:
10198765
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
American Association for the Advancement of Science (AAAS)
Date Published:
Journal Name:
Science
Volume:
370
Issue:
6512
ISSN:
0036-8075
Page Range / eLocation ID:
p. 95-101
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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