The stacking-fault energy of nickel

Carter, C. B.; Holmes, S. M.

doi:10.1080/14786437708232942

Cited by 255 publications

(64 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[21,22] In particular, the dissociation width of the edge dislocation is quantitatively well reproduced by this potential. In our simulations, the dissociation width equals 3.3 nm, which agrees with the observations of Carter and Holmes [23] who estimate this width, between 1.8 and 3.6 nm. For pure aluminum we chose the potential proposed by Voter and Chen, [24] which has the drawback of yielding a low stacking fault energy (compared e.g.…”

Section: Simulation Methods and Simulation Cellsupporting

confidence: 81%

Atomic-scale study of dislocation glide in a model solid solution

Proville

Rodney²,

Bréchet

et al. 2006

Philosophical Magazine

View full text Add to dashboard Cite

International audienceBased on atomic scale simulation techniques, we study the dislocation pinning mechanism in a dilute Ni(Al) model solid solution. For a solute concentration between 1 and 10 at. %, we found that the pinning of the dislocation on obstacles made of Al pairs is an interaction that operates significantly. The statistics of the dislocation motion is then modified accordingly to the nature of the obstacles and follows a modified Mott-Nabarro statistics. Finally, a method to address thermal activation is proposed and exemplified on a periodic row of solute

show abstract

Section: Simulation Methods and Simulation Cellsupporting

confidence: 81%

Atomic-scale study of dislocation glide in a model solid solution

Proville

Rodney²,

Bréchet

et al. 2006

Philosophical Magazine

View full text Add to dashboard Cite

show abstract

“…[30] The second stage corresponds to a roughly constant hardening rate h II . Multiple slips of dislocations then occur leading to the formation of cells of dislocations for materials with high stacking fault energy such as nickel (around 150 mJ/m 2 [31] ). It can be observed that h II strongly decreases with the thickness.…”

Section: A Work Hardening Evolution and Surface Effects Characterizamentioning

confidence: 99%

Intrinsic Effects due to the Reduction of Thickness on the Mechanical Behavior of Nickel Polycrystals

Hug

Keller

2010

Metall Mater Trans A

View full text Add to dashboard Cite

Uniaxial tensile tests were performed on high-purity nickel polycrystals with thicknesses (t) ranging from 12.5 to 3200 lm. The grain size (d) of each sample was set to a value close to 100 lm in order to avoid grain size effects. Experimental results highlight the intrinsic effect of the thickness on the mechanical properties of nickel. For plastic strains higher than 0.01, a strong softening of the flow stress is clearly observed when the t/d ratio decreases from four to one. This critical range is independent of the plastic strain. Transmission electron microscopy (TEM) investigations of dislocation structures were carried out in core and surface regions of samples plastically strained in the second hardening stage. It is shown that the mean dislocation cell diameter obtains values two or three times higher near free surfaces than in core areas for specimens with t/d ratios lying at a range of 1 to 4. This observation can be interpreted in terms of an increase in the mean free path of mobile dislocations in the second hardening stage. The transition between polycrystal and single-crystal behavior for nickel with constant grain size and various thicknesses is, therefore, an intrinsic effect related to progressively stronger surface softening effects.

show abstract

“…Transmission electron microscopy (TEM) imaging is widely used in that purpose, for it provides insight into individual defect configuration at the near atomic level. For instance, in the case of dislocations, TEM is used to size nanometric dissociation distances so as to obtain the stacking fault energy (Baluc and Schä ublin, 1996;Carter and Holmes, 1977;Hemker and Mills, 1993;Stobbs and Sworn, 1971) or to deduce the dislocation core configuration in ordered alloys (Kumar et al, 1999;Lang et al, 2004). In the case of radiation damage, the point defects, interstitials, vacancies or impurities, generated by the impinging energetic particles condense to form nanometric three-dimensional defects or clusters that eventually may transform in stacking fault tetrahedra (SFT), dislocation loops, cavities, which are voids when empty or bubbles when filled with a gas, or secondary phase precipitates.…”

Section: Introductionmentioning

confidence: 99%

Nanometric crystal defects in transmission electron microscopy

Schäublin

2006

Microscopy Res & Technique

View full text Add to dashboard Cite

Transmission electron microscopy (TEM) is revisited in order to define methods for the identification of nanometric defects. Nanometric crystal defects play an important role as they influence, generally in a detrimental way, physical properties. For instance, radiation-induced damage in metals strongly degrades mechanical properties, rendering the material stronger but brittle. The difficulty in using TEM to identify the nature and size of such defects resides in their small size. TEM image simulations are deployed to explore limits and possible ways to improve on spatial resolution and contrast. The contrast of dislocation loops, cavities, and a stacking fault tetrahedra (SFT) are simulated in weak beam, interfering reflections (HRTEM), and scanned condensed electron probe (STEM) mode. Results indicate that STEM is a possible way to image small defects. In addition, a new objective aperture is proposed to improve resolution in diffraction contrast. It is investigated by simulations of the weak beam imaging of SFT and successfully applied in experimental observations.

show abstract

The stacking-fault energy of nickel

Cited by 255 publications

References 33 publications

Atomic-scale study of dislocation glide in a model solid solution

Atomic-scale study of dislocation glide in a model solid solution

Intrinsic Effects due to the Reduction of Thickness on the Mechanical Behavior of Nickel Polycrystals

Nanometric crystal defects in transmission electron microscopy

Contact Info

Product

Resources

About