Slip in aluminum crystals containing strong, plate-like particles
TL;DR: In this article, the authors used a diffractometer technique and electron microscopy to study slip in two phase alloys of Al containing 2, 3 and 4 wt. % Cu, aged to give θ' plates.
About: This article is published in Acta Metallurgica.The article was published on 1970-08-01. It has received 110 citations till now. The article focuses on the topics: Slip (materials science) & Crystal.
Citations
More filters
TL;DR: In this paper, a deformation theory of plasticity is introduced to represent in a phenomenological manner the relative roles of strain hardening and strain gradient hardening, which is a non-linear generalization of Cosserat couple stress theory.
Abstract: Dislocation theory is used to invoke a strain gradient theory of rate independent plasticity. Hardening is assumed to result from the accumulation of both randomly stored and geometrically necessary dislocation. The density of the geometrically necessary dislocations scales with the gradient of plastic strain. A deformation theory of plasticity is introduced to represent in a phenomenological manner the relative roles of strain hardening and strain gradient hardening. The theory is a non-linear generalization of Cosserat couple stress theory. Tension and torsion experiments on thin copper wires confirm the presence of strain gradient hardening. The experiments are interpreted in the light of the new theory.
3,266 citations
1,775 citations
TL;DR: In this paper, a variation of the Orowan equation is developed for aluminium alloys strengthened by dispersed, deformation-resistant α precipitate plates, and the quantitative effects of precipitate volume fraction, number density and aspect ratio on increments in orowan strengthening are examined.
236 citations
TL;DR: In this paper, a two-dimensional model composite with elastic reinforcements in a crystalline matrix subject to macroscopic shear is analyzed using both discrete dislocation plasticity and conventional continuum slip crystal plasticity.
212 citations
TL;DR: In this article, an experimental investigation of local lattice rotations at non-deformable second phase particles in the size range 0.02 to 5 μm in aluminium and copper single crystals deformed to tensile strains of up to 0.5 is reported.
211 citations
References
More filters
Book•
01 Jun 1977
TL;DR: Hirsch et al. as mentioned in this paper described further experiments on the preparation of thin film sections of embedded Backscatter Kikuchi diffraction in the SEM for identification of crystallographic thin films by electron microscopy.
Abstract: In continuation of an earlier publication (Hoppe et al., 1968), further experiments are described here on the preparation of thin film sections of embedded Backscatter Kikuchi diffraction in the SEM for identification of crystallographic thin films by electron microscopy Peter B. Hirsch, Electron Works by Peter B. Hirsch: Electron Microscopy of Thin Crystals Peter B. Hirsch Author of Electron Microscopy of Thin Crystals
4,077 citations
TL;DR: The geometrically necessary dislocations as discussed by the authors were introduced to distinguish them from the statistically storages in pure crystals during straining and are responsible for the normal 3-stage hardening.
Abstract: Many two-phase alloys work-harden much faster than do pure single crystals. This is because the two phases are not equally easy to deform. One component (often dispersed as small particles) deforms less than the other, or not at all, so that gradients of deformation form with a wavelength equal to the spacing between the phases or particles. Such alloys are ‘plastically non-homogeneous’, because gradients of plastic deformation are imposed by the microstructure. Dislocations are stored in them to accommodate the deformation gradients, and so allow compatible deformation of the two phases. We call these ‘geometrically-necessary’ dislocations to distinguish them from the ‘statistically-stored’ dislocations which accumulate in pure crystals during straining and are responsible for the normal 3-stage hardening. Polycrystals of pure metals are also plastically non-homogeneous. The density and arrangement of the geometrically-necessary dislocations can be calculated fairly exactly and checked by electr...
3,527 citations
482 citations
TL;DR: In this paper, general equations for calculating the shear strain and shear stress in ideal double glide from the change in length, load and initial orientation of specimens tested in tension and compression are given.
Abstract: General equations are given for calculating the shear strain and the shear stress in ideal double glide from the change in length, load and initial orientation of specimens tested in tension and compression. The equations are applied to some special cases of interest, including glide on both {110} and {211} type planes in b.c.c. crystals, and the theoretically unstable form of double glide on primary and critical planes which has been found experimentally in some niobium crystals.
66 citations
TL;DR: In this article, single crystals were grown in aluminum-copper alloys containing from 3 to 5 per cent copper and they were strained in tension after receiving heat treatments designed to develop CuAl 2 particles of varying sizes and distributions.
60 citations