Ab initio modeling of slip activity in body-centered cubic chromium

Slip activity in body-centered cubic chromium is modeled by means of ab initio calculation of screw dislocations core properties and Peierls potential. As dislocations having 1 / 2 (111) Burgers vector and also (100 ), both gliding in {110} crystallographic planes have been reported experimentally, both screw dislocations are modeled. A generalized yield criterion incorporating physical ingredients necessary to account for deviations from the Schmid law is obtained for (111 ){110} and (100){110} slip systems. We report a broad range of crystal orientations for which (100) screw dislocations are easier to activate than the conventional 1/2(111) in tension and compression. These results hold for both the non-magnetic and antiferromagnetic phases of body-centered cubic chromium, with only a marginal effect of magnetism. (c) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Automated summary

In this study, slip activity in body-centered cubic chromium was modeled by calculating the core properties and Peierls potential of screw dislocations using ab initio methods. It was found that screw dislocations with different Burgers vectors have different activation capabilities in various crystal orientations, and a broad range of crystal orientations was identified.