Journal ArticleDOI
The Orowan mechanism in anisotropic crystals
R.O. Scattergood,David Bacon +1 more
Reads0
Chats0
TLDR
The static equilibrium configurations of a dislocation bypassing a periodic row of impenetrable circular obstacles were obtained for various crystals by means of a self-stress method wherein the elastic anisotropy of the crystal and the dislocation self-interaction could be taken into account.Abstract:
The static equilibrium configurations of a dislocation bypassing a periodic row of impenetrable circular obstacles were obtained for various crystals by means of a self-stress method wherein the elastic anisotropy of the crystal and the dislocation self-interaction could be taken into account. A correlation was developed from the results which related the Orowan stress values to the obstacle size and spacing. This correlation demands two parameters to account for the anisotropy, and these appear as a suitably defined anisotropic shear modulus and Poisson's ratio. The self-interactions are taken into account by a single logarithmic parameter which is the harmonic mean of the obstacle size and spacing, and is independent of anisotropy. The shapes of the bowing dislocation loops are strongly influenced by the anisotropy and interactions. The combined effects on shape can bo simply described in the line-tension framework, using the de Wit—Koehler solutions. In particular, the swept areas and overall ...read more
Citations
More filters
Journal ArticleDOI
Simulation of the interaction between an edge dislocation and a 〈1 0 0〉 interstitial dislocation loop in α-iron
TL;DR: In this article, the authors investigate the interaction of edge dislocations with interstitial dislocation loops in α-iron at 300 K and show that dislocation reactions are wide-ranging and complex, but can be described in terms of conventional dislocations reactions in which Burgers vector is conserved.
Journal ArticleDOI
High-temperature strength characterization of advanced 9Cr-ODS ferritic steels
Shigeharu Ukai,Shigeharu Ukai,Satoshi Ohtsuka,Takeji Kaito,Hideo Sakasegawa,N. Chikata,Shigenari Hayashi,Soumei Ohnuki +7 more
TL;DR: In this paper, it was found that 9Cr-ODS ferritic steels behave as fiber composite materials comprising the harder residual ferrite and the softer tempered martensite.
Journal ArticleDOI
Strengthening in a WE54 magnesium alloy containing SiC particles
TL;DR: The microstructure and the mechanical properties of the WE54 magnesium alloy reinforced by 13% of silicon carbide particulates were studied in this paper, where the composite material was prepared using a powder-metallurgical technique.
Journal ArticleDOI
The self-force on a planar dislocation loop in an anisotropic linear-elastic medium
S.D. Gavazza,David M. Barnett +1 more
TL;DR: In this article, a proper prescription for the in-plane self-force on each element of a plane dislocation loop is developed by computing the first variation of the loop self-energy during an arbitrary virtual planar change in the loop configuration.
Journal ArticleDOI
Atomistic simulations and continuum modeling of dislocation nucleation and strength in gold nanowires
TL;DR: In this article, the energetics of dislocation nucleation in gold nanowires are computed using atomistic simulations, and transition state theory is used to estimate the strength at experimental strain rates revealing detailed information outside the realm accessible to molecular dynamics simulations.
References
More filters
Book
Theory of Dislocations
John Price Hirth,Jens Lothe +1 more
TL;DR: Dislocations in Isotropic Continua: Effects of Crystal Structure on Dislocations and Dislocation-Point-Defect Interactions at Finite temperatures.
Journal ArticleDOI
The effect of dislocation self-interaction on the Orowan stress
TL;DR: In this article, the effect of dislocation self-interaction on the Orowan stress was determined for collinear, impenetrable circular obstacles, and an appropriate integro-differential equation governing static equilibrium was solved by an algorithm based on curvature adjustments.
Journal ArticleDOI
The self-stress of dislocations and the shape of extended nodes
TL;DR: In this article, a definition of the self-stress of a dislocation is proposed which is closely related to the more usual notion of a line tension, enabling a numerical calculation to be made of the shape of extended nodes in dislocation networks, and such a calculation leads to revised values of stacking-fault energies of alloys.
Journal ArticleDOI
Interaction of Dislocations with an Applied Stress in Anisotropic Crystals
G. deWit,J. S. Koehler +1 more
TL;DR: In this article, the equilibrium shape of a dislocation segment between two pinning points in the same glide plane is calculated using an energy per unit length, which is a function only of the angle between the Burgers vector and the tangent to the dislocation.