Interatomic potentials for modelling radiation defects and dislocations in tungsten

Marinica, Mihai-Cosmin; Ventelon, Lisa; Gilbert, Mark R.; Proville, Laurent; Dudarev, S. L.; Marian, Jaime; Bencteux, Guy; Willaime, F.

doi:10.1088/0953-8984/25/39/395502

Cited by 243 publications

(218 citation statements)

References 70 publications

(141 reference statements)

Supporting

Mentioning

203

Contrasting

Unclassified

Order By: Relevance

“…Currently, there have been many published interatomic potentials [15; 16; 17; 18; 19; 20; 21; 22] used to describe the W-W interaction. Based on the benchmark by Bonny et al [23], EAM4 produced by Marinica et al [21] (abbreviated as Marinica4) was used in this work, since the Marinica4 potential clearly reproduces dislocation behaviour. As was performed earlier [7; 13; 24; 25; 26], the potential was first connected with a ZBL universal potential [27] to ensure short-range reliability.…”

Section: Simulation Methodsmentioning

confidence: 99%

Effect of collision cascades on dislocations in tungsten: A molecular dynamics study

Fitzgerald

Hou

et al. 2017

Nuclear Instruments and Methods in Physics Research Section B:

View full text Add to dashboard Cite

Tungsten (W) is the prime candidate material for the divertor and other plasma-facing components in DEMO. The point defects (i.e. vacancies and self-interstitials) produced in collision cascades caused by incident neutrons aggregate into dislocation loops (and voids), which strongly affect the mechanical properties. The point defects also interact with existing microstructural features, and understanding these processes is crucial for modelling the long term microstructural evolution of the material under fusion conditions. In this work, we performed molecular dynamics simulations of cascades interacting with initially straight edge dislocation dipoles. It was found that the residual vacancy number usually exceeds the residual interstitial number for cascades interacting with vacancy type dipoles, but for interstitial type dipoles these are close. We observed that a cascade near a dislocation promotes climb, i.e. it facilitates the movement of point defects along the climb direction. We also observed that the dislocations move easily along the glide direction, and that kinks are formed near the centre of the cascade, which then facilitate the movement of the dipoles. Some dipoles are sheared off by the cascade, and this is dependent on PKA energy, position, direction, and the width of dipole.

show abstract

Section: Simulation Methodsmentioning

confidence: 99%

Effect of collision cascades on dislocations in tungsten: A molecular dynamics study

Fitzgerald

Hou

et al. 2017

Nuclear Instruments and Methods in Physics Research Section B:

View full text Add to dashboard Cite

show abstract

“…The majority of the potentials developed for W [29][30][31][32][33][34][35][36][37][38][39] adopt the embedded atom model (EAM), where the total energy, U tot is given as:…”

Section: Development Of the Te-dependent Potentialmentioning

confidence: 99%

Dynamical simulations of an electronically induced solid-solid phase transformation in tungsten

et al. 2015

View full text Add to dashboard Cite

The rearrangement of a material's electron density during laser irradiation leads to modified non-thermal forces on the atoms that may lead to coherent atomic motions and structural phase transformations on very short timescales. We present ab initio molecular dynamics simulations of a martensitic solid-solid phase transformation in tungsten under conditions of strong electronic excitation. The transformation is ultrafast, taking just over a picosecond, and follows the tetragonal Bain path. To examine whether a solid-solid bccfcc phase transformation could occur during laser irradiation, we use two-temperature molecular dynamics (2T-MD) simulations with a specially developed potential dependent on the electronic temperature. Our simulations show that the occurrence of the solid-solid phase transformation is in competition with ultrafast non-thermally assisted melting with the strength of the electron-phonon coupling determining the lifetime of the new solid phase. In tungsten the melting transition is predicted to occur too rapidly for the fcc phase to be detectable during laser irradiation.

show abstract

“…off-centered position of H displaced along <100> direction), however the resulting H-vacancy binding energy slightly differs from the ab initio result. Both EAM potentials were based on the interatomic potential for bcc W named "EAM2" from work [12]. The choice was made after critical review of 19 different EAM potentials given in [13].…”

Section: Computational Detailsmentioning

confidence: 99%

Interaction of hydrogen with dislocations in tungsten: An atomistic study

Grigorev

Terentyev

Bonny

et al. 2015

Journal of Nuclear Materials

View full text Add to dashboard Cite

The interaction of interstitial hydrogen with a dislocation and point defects in tungsten is studied by means of atomistic simulations. Two different types of interatomic potentials were tested by comparing their results with available ab initio data. The recently developed embedded atom method potential showed a better agreement with ab initio results than the bond order potential. Static calculations involving screw and edge dislocations showed that hydrogen is attracted to the dislocation core in both cases. It is also found that hydrogen atoms prefer to arrange themselves as elongated clusters on dislocation lines. Molecular dynamics simulations of hydrogen migration along the edge dislocation core confirmed the results of the static calculations and demonstrated a strong attraction to the dislocation core and one-dimensional migration along it.

show abstract

Interatomic potentials for modelling radiation defects and dislocations in tungsten

Cited by 243 publications

References 70 publications

Effect of collision cascades on dislocations in tungsten: A molecular dynamics study

Effect of collision cascades on dislocations in tungsten: A molecular dynamics study

Dynamical simulations of an electronically induced solid-solid phase transformation in tungsten

Interaction of hydrogen with dislocations in tungsten: An atomistic study

Contact Info

Product

Resources

About