Cluster Dynamics Modeling of Materials: Advantages and Limitations

The aim of this paper is to give a short review on cluster dynamics modeling in the field of atoms and point defects clustering in materials. It is shown that this method, due to its low computer cost, can handle long term evolution that cannot, in many cases, be obtained by Lattice Kinetic Monte Carlo methods. Indeed, such a possibility is achieved thanks to an important drawback that is the loss of space correlations of the elements of the microstructures. Some examples, in the field of precipitation and irradiation of metallic materials are given. The limitations and difficulties of this method are also discussed. Unsurprisingly, it is shown that it goes in a very satisfactory way when the objects are distributed homogeneously. Conversely, the source term describing the primary damage under irradiation, by nature heterogeneous in space and time, is tricky to introduce especially when displacement cascades are produced.

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Kinetic Monte Carlo simulations of cascades in Fe alloys

MRS Proceedings ◽

10.1557/proc-650-r3.25 ◽

2000 ◽

Vol 650 ◽

Cited By ~ 7

Author(s):

C. Domain ◽

C.S. Becquart ◽

J.C. van Duysen

Keyword(s):

Monte Carlo ◽

Kinetic Monte Carlo ◽

Md Simulations ◽

Atom Probe ◽

Pressurized Water Reactor ◽

Pressurized Water ◽

Displacement Cascades ◽

Cu Content ◽

Primary Damage ◽

Eam Potential

ABSTRACTThe Pressurized Water Reactor vessel steels are embrittled by neutron irradiation. Among the solute atoms, copper play an important role in the embrittlement and different Cu-rich defects have been experimentally observed to form. We have investigated by Kinetic Monte Carlo (KMC) on rigid lattices the evolution of the primary damage. Since the point defects created by the displacement cascades have very different kinetics, their evolution is tracked in two steps. In a first step, we have studied their recombination in the cascade region and the formation of interstitial clusters using “object diffusion”. The parameters of this model are based on MD simulations, or on first principles calculations. In a second part, we have investigated the subsequent evolution of the primary damage with a model based on a vacancy jump mechanism. These simulations which rely on an adapted EAM potential show the formation of copper rich defects. Some of the potential's predictions that played a key role in the model were checked by ab initio calculations. The defects obtained from these simulations, subsequent to the primary damage created by displacement cascades, exhibit similarities with the ones observed by atom probe. The influence of temperature and Cu content on the final damage was investigated.

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KIMERA: A Kinetic Montecarlo Code for Mineral Dissolution

Minerals ◽

10.3390/min10090825 ◽

2020 ◽

Vol 10 (9) ◽

pp. 825

Author(s):

Pablo Martin ◽

Juan J. Gaitero ◽

Jorge S. Dolado ◽

Hegoi Manzano

Keyword(s):

Monte Carlo ◽

Dissolution Rate ◽

Point Defects ◽

Open Source Software ◽

Kinetic Monte Carlo ◽

Object Oriented ◽

Mineral Dissolution ◽

Atomic Scale ◽

Mineral Structure ◽

Scientific Tool

KIMERA is a scientific tool for the study of mineral dissolution. It implements a reversible Kinetic Monte Carlo (KMC) method to study the time evolution of a dissolving system, obtaining the dissolution rate and information about the atomic scale dissolution mechanisms. KIMERA allows to define the dissolution process in multiple ways, using a wide diversity of event types to mimic the dissolution reactions, and define the mineral structure in great detail, including topographic defects, dislocations, and point defects. Therefore, KIMERA ensures to perform numerous studies with great versatility. In addition, it offers a good performance thanks to its parallelization and efficient algorithms within the KMC method. In this manuscript, we present the code features and show some examples of its capabilities. KIMERA is controllable via user commands, it is written in object-oriented C++, and it is distributed as open-source software.

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Modeling the long-term evolution of the primary damage in ferritic alloys using coarse-grained methods

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2010.05.019 ◽

2010 ◽

Vol 406 (1) ◽

pp. 39-54 ◽

Cited By ~ 57

Author(s):

C.S. Becquart ◽

A. Barbu ◽

J.L. Bocquet ◽

M.J. Caturla ◽

C. Domain ◽

...

Keyword(s):

Long Term Evolution ◽

Coarse Grained ◽

Ferritic Alloys ◽

Term Evolution ◽

Primary Damage

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Diffusion in the AlMo3 Ordered Intermetallic

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.272.51 ◽

2008 ◽

Vol 272 ◽

pp. 51-60

Author(s):

M.I. Pascuet ◽

Julián R. Fernández ◽

A.M. Monti

Keyword(s):

Monte Carlo ◽

Point Defects ◽

Interatomic Potential ◽

Kinetic Monte Carlo ◽

Statistical Thermodynamics ◽

Monte Carlo Technique ◽

Vacancy Mechanism ◽

Ordered Intermetallic ◽

Equilibrium Concentrations

An EAM interatomic potential for the ordered AlMo3 intermetallic is developed and applied to the study of point defects in the AlMo3. The equilibrium concentrations of vacancies and antisites are calculated using statistical thermodynamics. Results show that antisites are the most abundant type of defect in a range of temperatures and compositions close to stoichiometry. Finally, the diffusion by vacancy mechanism in the same structure is studied through the kinetic Monte Carlo technique. Possible atomic mechanisms of diffusion are suggested and analyzed in some detail.

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The Role of Surface Annihilation in Annealing Investigated by Atomic Model Simulation

MRS Proceedings ◽

10.1557/proc-864-e9.9 ◽

2005 ◽

Vol 864 ◽

Cited By ~ 1

Author(s):

Min Yu ◽

Xiao Zhang ◽

Ru Huang ◽

Xing Zhang ◽

Yangyuan Wang ◽

...

Keyword(s):

Monte Carlo ◽

Integrated Circuits ◽

Point Defects ◽

Model Simulation ◽

Kinetic Monte Carlo ◽

Boron Diffusion ◽

Junction Depth ◽

Kinetic Monte Carlo Method ◽

Enhanced Diffusion

AbstractBehavior of point defects in annealing is investigated a lot in order to suppress the Transient Enhanced Diffusion (TED) of boron as is urged by the development of integrated circuits. Surface annihilation possibility for point defects is very important in determining junction depth in the case of ultra-shallow doping. However the understanding on it is still ambiguous considering the inconsistent results on surface annihilation behavior. In this paper the variation of surface annihilation possibility is studied. The simulation on boron diffusion as well as silicon diffusion is performed. The evolution of Si clusters is simulated. By explaining experimental results with Kinetic Monte Carlo method based simulation, we proposed that surface annihilation possibility varies in different cases.

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Enforcing local equilibrium of point defects near sinks in object kinetic Monte Carlo simulations

Modelling and Simulation in Materials Science and Engineering ◽

10.1088/1361-651x/abe0a9 ◽

2021 ◽

Author(s):

Thomas Jourdan

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Point Defects ◽

Kinetic Monte Carlo ◽

Local Equilibrium ◽

Object Kinetic Monte Carlo ◽

Kinetic Monte Carlo Simulations

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Multiscale Modeling of Helium-Vacancy Cluster Nucleation under Irradiation: A Kinetic Monte-Carlo Approach

MRS Proceedings ◽

10.1557/proc-1215-v05-07 ◽

2009 ◽

Vol 1215 ◽

Author(s):

Tomoaki Suzudo ◽

Masatake Yamaguchi ◽

Hideo Kaburaki ◽

Ken-ichi Ebihara

Keyword(s):

Monte Carlo ◽

Ab Initio ◽

Point Defects ◽

Kinetic Monte Carlo ◽

Monte Carlo Model ◽

Vacancy Cluster ◽

Austenitic Steels ◽

Vacancy Clusters ◽

Dissociation Energies ◽

Object Kinetic Monte Carlo

AbstractWe applied ab initio calculation and an object kinetic Monte Carlo modeling to the study of He-vacancy cluster nucleation under irradiation in bcc and fcc Fe, which are surrogate materials for ferritic/martensitic and austenitic steels, respectively. The ab initio calculations provided parameters for the object kinetic Monte Carlo model, such as the migration energies of point defects and the dissociation energies of He and vacancy to He-vacancy clusters. We specially focused on the simulation of high He/dpa irradiation such as He-implantation into the materials and tracked the nucleation of clusters and the fate of point defects such as SIAs, vacancies, and He atoms. We found no major difference of He-vacancy cluster nucleation between bcc and fcc Fe when we ignore the intracascade clustering even if the migration energies of point defects are significantly different between the two crystals.

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New Perspectives for the Spent Nuclear Fuel Radionuclides Release Model in a Deep Geological Repository

MRS Proceedings ◽

10.1557/proc-985-0985-nn02-06 ◽

2006 ◽

Vol 985 ◽

Cited By ~ 2

Author(s):

Christophe Poinssot ◽

Cécile FERRY ◽

Arnaud POULESQUEN

Keyword(s):

Nuclear Fuel ◽

Source Term ◽

Spent Nuclear Fuel ◽

Deep Geological Repository ◽

Term Evolution ◽

Geological Repository ◽

Definition Of ◽

Release Model ◽

The Impact

AbstractSpent Nuclear Fuel (SNF) source terms are used to define the release rate of radionuclides (RN) in a direct disposal and to assess the performance of this waste form. They classically distinguish between two contributions: (i) the Instant Release Fraction (IRF) of RN which are directly leached when water contacts the fuel, (ii) the slow and long term release of RN which are embedded within the fuel matrix. Recent experimental results bring significant input in our understanding and assessment of both contributions. However, they have not yet been integrated in the definition of the SNF source term. This paper will present the impact on the RN source term of the latest results on the SNF long term evolution and the key remaining scientific issues.

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The Assessment of the Long-Term Evolution of the Spent Nuclear Fuel Matrix by Kinetic, Thermodynamic and Spectroscopic Studies of Uranium Minerals.

MRS Proceedings ◽

10.1557/proc-353-633 ◽

1994 ◽

Vol 353 ◽

Cited By ~ 9

Author(s):

Jordi Bruno ◽

I. Casas ◽

E Cera ◽

R. C. Ewing ◽

R. J. Finch ◽

...

Keyword(s):

Nuclear Fuel ◽

Safety Assessment ◽

Source Term ◽

Spent Nuclear Fuel ◽

Spectroscopic Studies ◽

Spent Fuel ◽

Term Evolution ◽

Uranium Minerals ◽

The Stability

AbstractThe long term behaviour of spent nuclear fuel is discussed in the light of recent thermodynamic and kinetic data on mineralogical analogues related to the key phases in the oxidative alteration of uraninite. The implications for the safety assessment of a repository of the established oxidative alteration sequence of the spent fuel matrix are illustrated with Pagoda calculations. The application to the kinetic and thermodynamic data to source term calculations indicates that the appearance and duration of the U(VI) oxyhydroxide transient is critical for the stability of the fuel matrix.

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