Shockwave generates < 100 > dislocation loops in bcc iron

Fast, vacancy-free climb of prismatic dislocation loops in bcc metals

Vacancy-mediated climb models cannot account for the fast, direct coalescence of dislocation loops seen experimentally. An alternative mechanism, self climb, allows prismatic dislocation loops to move away from their glide surface via pipe diffusion around the loop perimeter, independent of any vacancy atmosphere. Despite the known importance of self climb, theoretical models require a typicall...

“Conjugate Channeling” Effect in Dislocation Core Diffusion: Carbon Transport in Dislocated BCC Iron

Dislocation pipe diffusion seems to be a well-established phenomenon. Here we demonstrate an unexpected effect, that the migration of interstitials such as carbon in iron may be accelerated not in the dislocation line direction ξ, but in a conjugate diffusion direction. This accelerated random walk arises from a simple crystallographic channeling effect. c is a function of the Burgers vector b,...

First-principles Calculation on Core Structures and Peierls Stress of a Screw Dislocation in BCC Iron

Predicting atomistic properties of a dislocation is a first step toward an understanding of plastic behavior of materials, in particular BCC metals. The core structure and Peierls stress of a screw dislocation in BCC iron have been determined using the first-principles calculations based on the density functional theory with the large-scale supercell containing 231 atoms. For the a0/2[111] scre...

Magnetic coupling in 3d transition-metal monolayers and bilayers on bcc (100) iron.

Stability of Dislocation Short-Range Reactions in BCC Crystals

The stability of short-range reactions between two dislocations of parallel line vectors which glide on two parallel slip planes in BCC crystals is determined. The two dislocations are assumed to be infinitely long, and their interaction is treated as elastic. The interaction and self-energies are both computed for dynamically moving dislocations, where the dependence on dislocation velocity is...