Results 211 to 220 of about 3,974 (264)

Grain-Boundary Sliding

Nature, 1962
WHEN bicrystals are subjected to a constant shear stress parallel to the boundary plane, the grain boundary sliding velocity decreases with time1–4. We wish to report some experiments which demonstrate the important part played by crystal slip in determining this characteristic of boundary sliding.
R. L. BELL, N. B. W. THOMPSON
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Sliding Mechanisms in Aluminum Grain Boundaries

Physical Review Letters, 1997
We present a detailed investigation, based on ensemble density functional theory simulations, of the microscopic mechanisms that accompany the sliding of grain boundaries in aluminum, a typical ductile metal. We find a variety of sliding behaviors, including coupling to migration, that depend not only on the delocalized character of the metallic ...
Molteni, C, Marzari, N, Payne, M C, Heine, V   +3 more
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Anelasticity and grain boundary sliding

Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2010
We describe a theoretical and numerical analysis of an existing model of anelasticity owing to grain boundary sliding. Two linearly elastic layers having finite thickness and identical material constants are separated by a given fixed spatially periodic interface across which the normal component
Lee, L. C., Morris, S. J. S.
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On the grain boundary conditions for grain boundary sliding in superplastic deformation

Materials Science and Engineering, 1986
Abstract Grain boundary sliding (GBS) is analysed in terms of the rate of formation and the rate of spreading of extrinsic grain boundary dislocations (EGBDs). It is calculated employing a mathematical model derived in such a way that in superplastic alloys, where GBS is a primary deformation mode, the rate of EGBD spreading is at least equal to or ...
R.A. Varin, K.J. Kurzydlowski, K. Tangri
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Effect of extrinsic grain-boundary defects on grain-boundary sliding resistance

Philosophical Magazine A, 1999
Abstract A computer simulation was performed to examine the role of extrinsic grain-boundary (GB) defects in the sliding of the {11, (101){131} symmetric tilt boundary in aluminium by means of an embedded-atom method potential. The sliding resistance of the equilibrium GB was determined from a computation of the dependence of the boundary energy on in ...
R. J. Kurtz, R. G. Hoagland, J. P. Hirth
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Ab Initio Investigation of Grain Boundary Sliding

MRS Proceedings, 1995
AbstractWe are using total energy pseudopotential calculations to carry out an extensive investigation into grain boundary sliding in a number of different systems, in order to understand, at microscopic level, the fundamental mechanisms responsible for this process.In this paper we present results for the sliding process at the ∑ = 5(001) twist grain ...
Payne, M C, Francis, G P, Molteni, C, Marzari, N, Deyirmenjian, V, Heine, V   +5 more
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The Nature of Grain Boundary Sliding and the Superplastic Plow

Physica Status Solidi (a), 1983
Two types of grain boundary sliding are established and investigated during Zn bicrystal deformation: “pure” grain boundary sliding (GBS) which is not associated with intragranular sliding (IS) and GBS which develops simultaneously with IS. Both types of GBS exhibit greatly similar structural peculiarities but under identical deformation conditions the
R. Z. Valiev, O. A. Kaibyshev, V. V. Astanin, A. K. Emaletdinov   +3 more
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The role of grain boundary dislocations in grain boundary sliding

Acta Metallurgica, 1973
Abstract Dislocation models for grain boundary sliding have generally invoked lattice dislocations moving along the boundary as the basic mode of deformation. This paper considers the possibility of structural dislocations accounting for the same phenomenon.
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First Principles Simulation of Grain Boundary Sliding

Physical Review Letters, 1996
We present the results of a total-energy pseudopotential simulation of the sliding process at a $\ensuremath{\Sigma}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}5$ (001) twist grain boundary in germanium. Sliding involves a stick-slip mechanism with local rebonding among a few atoms, accompanied by the clearance of gap states.
Molteni, C, Francis, G P, Payne, M C, Heine, V   +3 more
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The role of partial grain boundary dislocations in grain boundary sliding and coupled grain boundary motion

Journal of Materials Science, 2006
We study the process of grain boundary sliding through the motion of grain boundary dislocations, utilizing molecular dynamics and embedded atom method (EAM) interatomic potentials. For a Σ = 5 [001]{310} symmetrical tilt boundary in bcc Fe, the sliding process was found to occur through the nucleation and glide of partial grain boundary dislocations ...
Joshua Monk, Brian Hyde, Diana Farkas
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