Dislocation drag and its influence on elastic precursor decay

Abstract

Plastic deformation is mediated by the creation and movement of dislocations, and at high stress the latter is dominated by dislocation drag from phonon wind. By simulating a 1-D shock impact problem we analyze the importance of accurately modeling dislocation drag and dislocation density evolution in the high stress regime. Dislocation drag is modeled according to a first-principles derivation as a function of stress and dislocation character, and its temperature and density dependence are approximated to the extent currently known. Much less is known about dislocation density evolution, leading to far greater uncertainty in these model parameters. In studying anisotropic fcc metals with character dependent dislocations, the present work generalizes similar earlier studies by other authors.

arXiv comment28 pages, 16 figures; v2 improved the presentation

References in corpus (10)

• Atomistic simulations of dislocation mobility in Al, Ni and Al/Mg alloys
• An analytic model of the Gruneisen parameter at all densities
• Velocity dependent dislocation drag from phonon wind and crystal geometry
• Dislocation drag from phonon wind in an isotropic crystal at large velocities
• Analytic model of the remobilization of pinned glide dislocations: including dislocation drag from phonon wind
• Properties of dislocation drag from phonon wind at ambient conditions
• Line tension of a dislocation moving through an anisotropic crystal
• Clarifying the definition of 'transonic' screw dislocations
• A general solution for accelerating screw dislocations in arbitrary slip systems with reflection symmetry
• Thermoelastic-Plastic Flow Equations in General Coordinates

Cited by in corpus (7)

• Limiting velocities and transonic dislocations in Mg
• How to determine limiting velocities of dislocations in anisotropic crystals
• On the temperature and density dependence of dislocation drag from phonon wind
• A general solution for accelerating screw dislocations in arbitrary slip systems with reflection symmetry
• Properties of accelerating edge dislocations in arbitrary slip systems with reflection symmetry
• PyDislocDyn: A Python code for calculating dislocation drag and other crystal properties
• Computationally efficient method for determining limiting velocities of edge dislocations in anisotropic crystals