A rationalization of secondary defect structures in aluminium-based alloys

Westmacott, K.H.; Peck, R. L.

doi:10.1080/14786437108216407

Cited by 67 publications

(19 citation statements)

References 23 publications

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“…Calculated and measured lattice constant, elastic constants (Mbar), and stacking fault energy (mJ=m 2 ) for fcc aluminum[23][24][25][26]. The VASP calculated values are based on different levels of approximation of the pseudopotentials and the local density approximation as described in the text.…”

mentioning

confidence: 99%

Prediction of Dislocation Cores in Aluminum from Density Functional Theory

et al. 2008

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The strain field of isolated screw and edge dislocation cores in aluminum are calculated using density-functional theory and a flexible boundary condition method. Nye tensor density contours and differential displacement fields are used to accurately bound Shockley partial separation distances. Our results of 5-7.5 A (screw) and 7.0-9.5 A (edge) eliminate uncertainties resulting from the wide range of previous results based on Peierls-Nabarro and atomistic methods. Favorable agreement of the predicted cores with limited experimental measurements demonstrates the need for quantum mechanical treatment of dislocation cores.

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confidence: 99%

Prediction of Dislocation Cores in Aluminum from Density Functional Theory

et al. 2008

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“…On the other hand, Deipers and co-workers found that irradiation of gold and copper with 1-5 keV argon ions to a dose of about lots ions cm-2 results in Frank loops forming at depths in the range 50-400 A with little defect loss or alignment. These results suggest therefore that the proximity of a surface influences loop geometry and the most obvious explanation is that surface image forces can promote unfaulting in a similar manner to misfit stresses around impurity atoms, as observed for example in quenched aluminium alloys (Westmacott and Peck 1971).…”

Section: F-02mentioning

confidence: 64%

“…However the formation of perfect loops is generally inhibited in quenched specimens because of the absence of suitable stresses to nucleate the necessary Shockley partial. Westmacott and Peck (1971) have quenched various aluminium alloys and have correlated the fraction of perfect loops formed to the atomic misfit and changes in ySF associated with the solute additions. They conclude that internal stress arising from misfitting solute atoms can nucleate the Shockley partials required to unfault loops.…”

Section: Aluminiummentioning

confidence: 99%

Self-wave processes in a wide-aperture laser with an additional nonlinear component

Zaikin

1996

Quantum Electron.

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The paper reviews the contribution that transmission electron microscopy has made to our understanding of the mobility and clustering of point defects in fcc and bcc metals. The first part of the paper considers the nucleation and growth of vacancy clusters in quenched fcc metals. Most of the results have been obtained for gold and aluminium and a good understanding has been achieved of the factors governing the type of defects that are nucleated in these metals. In the second part of the paper the complex subject of irradiation damage is discussed with emphasis being placed on showing the inter-relationship existing between basic damage processes governing defect production and the visible defect structure. A selfconsistent picture is now emerging of the damage structures produced by irradiation at low temperatures which provides a basis for understanding the sometimes very varied results obtained in different experiments. The third section of the paper discusses the observation of cluster growth and shrinkage in terms of the information they provide about defect mobility. In the final part of the paper a summary is presented of the main conclusions that can be drawn from electron microscope studies regarding the behaviour of vacancy and interstitial defects in fcc and bcc metals.

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“…Experimental (4 K) [27] 116 GPa 64.8 GPa 30.9 GPa 0.120 -0.144 J/m 2 [28,29] EAM Potential (0 K) [21] 119 GPa 62.3 GPa 34.9 GPa 0.135 J/m 2 constants and stacking fault energy predicted by this potential have been reported by Dontsova et al [24]. All simulations were performed using LAMMPS [25] while visualization and dislocation position were extracted using Ovito [26].…”

Section: Methodsmentioning

confidence: 99%

Atomistic insights into cluster strengthening in aluminum alloys

2018

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In certain naturally aged aluminum alloys, significant strengthening can be obtained due to the decomposition of a super-saturated solid solution into clusters. The origins of such strengthening remain unclear due to the challenge of differentiating solute cluster strengthening from solid solution or precipitate strengthening. To shed light on the origin of cluster strengthening in aluminum alloys, the interaction between the smallest possible type of clusters (i.e. dimers) and moving dislocations in a model Al-Mg alloy is studied using atomistic simulations. Additionally, theoretical models for both the parelastic and dielastic interactions between clusters and dislocations is used to identify which factor among order strengthening, elastic interaction, and change of stacking fault energy controls cluster strengthening. The comparison of the results from these models to that of the atomistic simulations show that in the case of Mg dimers, the strength of the strongest ones are dominated by the dielastic contribution through the change of stacking fault energy.

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A rationalization of secondary defect structures in aluminium-based alloys

Cited by 67 publications

References 23 publications

Prediction of Dislocation Cores in Aluminum from Density Functional Theory

Prediction of Dislocation Cores in Aluminum from Density Functional Theory

Self-wave processes in a wide-aperture laser with an additional nonlinear component

Atomistic insights into cluster strengthening in aluminum alloys

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