Multiplicity of dislocation pathways in a refractory multiprincipal element alloy

TitleMultiplicity of dislocation pathways in a refractory multiprincipal element alloy
Publication TypeJournal Article
Year of Publication2020
AuthorsWang F, Balbus GH, Xu S, Su Y, Shin J, Rottmann PF, Knipling KE, Stinville JCharles, Mills LH, Senkov ON, Beyerlein IJ, Pollock TM, Gianola DS
JournalScience
Volume370
Pagination95–101
ISSN10959203
Abstract

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.

DOI10.1126/science.aba3722
PubMed ID33004516