Atomistic simulations of dislocation mobility in refractory high-entropy alloys and the effect of chemical short-range order.

ABSTRACT: Refractory high-entropy alloys (RHEAs) are designed for high elevated-temperature strength, with both edge and screw dislocations playing an important role for plastic deformation. However, they can also display a significant energetic driving force for chemical short-range ordering (SRO). Here, we investigate mechanisms underlying the mobilities of screw and edge dislocations in the body-centered cubic MoNbTaW RHEA over a wide temperature range using extensive molecular dynamics simulations based on a highly-accurate machine-learning interatomic potential. Further, we specifically evaluate how these mechanisms are affected by the presence of SRO. The mobility of edge dislocations is found to be enhanced by the presence of SRO, whereas the rate of double-kink nucleation in the motion of sc

SUBMITTER: Yin S 

PROVIDER: S-EPMC8357793 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature