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Atomistic aspects of fracture

Erik Bitzek, James R. Kermode, Peter Gumbsch
2015 International Journal of Fracture  
This review focuses on atomistic aspects of fracture in crystalline materials where significant advances have been achieved over the last ten years and provides an outlook on future perspectives for atomistic  ...  new insights e.g. on the role of bond trapping, dynamic effects, crackmicrostructure interactions and chemical aspects on the fracture toughness and crack propagation patterns in metals and ceramics.  ...  Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s)  ... 
doi:10.1007/s10704-015-9988-2 fatcat:xyaqgz34xnetzj7eoaabawu3bq

Molecular dynamics simulations of stress-induced phase transformations and grain nucleation at crack tips in Fe

A Latapie, D Farkas
2003 Modelling and Simulation in Materials Science and Engineering  
fcc transition phase.  ...  The molecular dynamics simulation technique is used to study a stressinduced new grain formation mechanism at the crack tip of a nanocrystalline α-iron sample at temperatures ranging from 100 to 600 K.  ...  We specially acknowledge the help of Helena van Swyngehoven with the codes and techniques for the creation of polycrystalline digital samples.  ... 
doi:10.1088/0965-0393/11/5/303 fatcat:dkrqvs3x7ne75kmmtzd3i4hrqi

CONNECTING MOLECULAR DYNAMICS AND DISLOCATION DYNAMICS TO CONTINUUM IN HIERARCHICAL SIMULATIONS OF MICROCRACKS IN SOLIDS

Akihiro NAKATANI, Hiroshi KITAGAWA, Sidney YIP
1999 Journal of the Society of Materials Science Japan  
No precise mea- surements of the brittle-to-ductile transition temper- ature in a single crystal of ƒ¿-Fe is available.  ...  closer integration of atomistic simulations with DDD and FEM.  ... 
doi:10.2472/jsms.48.12appendix_241 fatcat:h3pwqhsfgbagdgfxenhcdqtpdi

Computational modeling and simulation of spall fracture in polycrystalline solids by an atomistic-based interfacial zone model

Liqiang Lin, Xiaowei Zeng
2015 Engineering Fracture Mechanics  
In addition, analysis of grain size, crystal lattice orientation and impact speed reveals that the spall strength increases as grain size or impact speed increases.  ...  The focus of this work is to investigate spall fracture in polycrystalline materials under high-speed impact loading by using an atomistic-based interfacial zone model.  ...  In the interfacial zone, the crystal lattice structure is modeled as hexagonal structure and the arrangement of atoms is regular in the undeformed state, but its lattice constants and atomistic potential  ... 
doi:10.1016/j.engfracmech.2015.05.039 pmid:26435546 pmcid:PMC4587396 fatcat:6bgwrnbvqjaffldihvwuv6teem

Atomistic simulations on ductile-brittle transition in ⟨111⟩ BCC Fe nanowires

G. Sainath, B. K. Choudhary
2017 Journal of Applied Physics  
Molecular dynamics simulations have been performed to understand the influence of temperature on the tensile deformation and fracture behavior of <111> BCC Fe nanowires.  ...  The change in fracture behavior has been discussed in terms of the relative variations in yield and fracture stresses and change in slip behavior with respect to temperature.  ...  The higher transition temperatures than In a single phase BCC Fe-Co alloy, Johnston et al.56 the bulk counterparts observed in the present investiga- have shown that the change in fracture  ... 
doi:10.1063/1.4999090 fatcat:l6tz422wbzahfaoey7ovvro6i4

Atomistic Simulation to Study the Fracture Behaviour in Cu-Zr Bulk Metallic Glass

Rahul Chug, Sachin Gupta
2017 International Journal of Engineering and Technology  
Computer simulation of fracture in single crystals has provided new insight into the stability of crack propagation, phenomena of lattice trapping, and the origins of brittle and ductile behavior.  ...  in fcc metallic plates [16] , ductile crack growth in an aluminum single crystal [17] , size effect study of magnesium single crystal [2,18] etc.  ...  It is interesting to note that Warner and Curtin [30] revealed similar simulation results where the twining re-emerged in Fe single crystal at high temperature.  ... 
doi:10.21817/ijet/2017/v9i3/170903059 fatcat:7hxsra5c65avlddkfo4orhxmwa

Fracture ab initio: A force-based scaling law for atomistically informed continuum models

Johannes J. Möller, Erik Bitzek, Rebecca Janisch, Hamad ul Hassan, Alexander Hartmaier
2018 Journal of Materials Research  
Here we use two atomistic methods to investigate cleavage fracture of brittle materials: (i) we analyze the forces in front of a sharp crack and (ii) we study the bond breaking process during rigid body  ...  In fracture mechanics, established methods exist to model the stability of a crack tip or the kinetics of crack growth on both the atomic and the macroscopic scale.  ...  RBS schemes can be used to characterize single crystals and grain boundaries on the same footing, 41 provide a threedimensional description of single crystal 42 and grain boundary separation, 43  ... 
doi:10.1557/jmr.2018.384 fatcat:pqoq43r5izefhiz6t3ikl6fceu

Molecular-dynamics simulation-based cohesive zone representation of intergranular fracture processes in aluminum

V. Yamakov, E. Saether, D.R. Phillips, E.H. Glaessgen
2006 Journal of the mechanics and physics of solids  
A traction-displacement relationship that may be embedded into a cohesive zone model for microscale problems of intergranular fracture is extracted from atomistic molecular-dynamics simulations.  ...  The preference for twinning to dislocation slip is in agreement with the predictions of the Tadmor and Hai criterion.  ...  The crystallographic orientations of Crystal I and Crystal II are presented in Fig. 2 which the atomic structure in Al is known from the literature (Dahmen, 1990) .  ... 
doi:10.1016/j.jmps.2006.03.004 fatcat:uqjj4qerbje3he6htg7r2u2hwi

Multiscale modeling of nano/micro systems by a multiscale continuum field theory

Xiaowei Zeng, Xianqiao Wang, James D. Lee, Yajie Lei
2010 Computational Mechanics  
In this work, the nanoscale size effect in single crystal bcc iron is studied, the phenomenon of wave propagation is simulated and wave speed is obtained.  ...  The theoretical construction of the continuum field theory will be briefly introduced. In the simulation model, a single crystal can be discretized into finite element mesh as in a continuous medium.  ...  Open Access This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided  ... 
doi:10.1007/s00466-010-0538-5 fatcat:ybiz67qprna3xdlmeq7d7o5jei

Effects of electric field on nanocrack propagation

Xianqiao Wang, James D. Lee
2011 International Journal of Fracture  
Single crystal MgO under electrical/mechanical loading is modeled and simulated.  ...  The present work is concerned with the application of Atomistic Field Theory (AFT) in modeling and simulation of dynamic nanocrack propagation under electrical and mechanical loadings.  ...  Atomistic field theory To provide the background for the subsequent developments, we briefly review the Atomistic Field Theory = + Fig. 1 Atomistic view of crystal structure constructed by Chen and her  ... 
doi:10.1007/s10704-010-9580-8 fatcat:zjgf7lhvlbf33dydjjsvespij4

Nanomechanics of Graphene and Nanocrystals

Wei Yang, Hongtao Wang
2014 Procedia IUTAM  
Simulations based on micro-structural evolution demonstrate the capability in predicting the brittle versus ductile transition of nanocrystal.  ...  These doping atoms serve to functionalize the edges and to create catalysts in the form of single atom arrays.  ...  Acknowledgements We acknowledge Advanced Nanofabrication, Imaging and Characterization Core Lab in King Abdullah University of Science and Technology for characterization facilities.  ... 
doi:10.1016/j.piutam.2014.01.023 fatcat:gvft4opvlbdc3lxgyc256n7ila

Atomic-scale modeling of superalloys [chapter]

Thomas Hammerschmidt, Jutta Rogal, Erik Bitzek, Ralf Drautz
2022 Nickel Base Single Crystals Across Length Scales  
In this chapter we give an overview of atomistic modeling and simulation for Ni-base superalloys.  ...  Methods to determine structural stability for different chemical compositions, thermodynamic and kinetic properties of typical defects in superalloys, and relations to mechanical deformation are discussed  ...  Prakash, and J.J. Möller for their help in preparing some of the figures.  ... 
doi:10.1016/b978-0-12-819357-0.00020-2 fatcat:nzzl7p5fkrgi5ketbamp7b6yie

Atomistic Studies of Nanoindentation—A Review of Recent Advances

Carlos Ruestes, Iyad Alhafez, Herbert Urbassek
2017 Crystals  
Topics covered include: nucleation of dislocations in ideal crystals, effect of surface orientation, effect of crystallography (fcc, bcc, hcp), effect of surface and bulk damage on plasticity, nanocrystalline  ...  In addition we discuss related features, such as the influence of tip geometry on the indentation and the role of adhesive forces, and how pre-existing plasticity affects nanoindentation.  ...  Figure 3 shows the indentation of a (100) Fe single crystal with pre-existing defects (vacancies, divacancies, voids, and dislocations).  ... 
doi:10.3390/cryst7100293 fatcat:mwvcxorukrdofole2ifvtvps3y

Multiscale modeling of the brittle to ductile transition

S.J Noronha, J Huang, N.M Ghoniem
2004 Journal of Nuclear Materials  
The brittle to ductile transition fracture toughness curve is obtained and compared to experiments.  ...  The dislocations shield the crack and result in an increase of the applied stress intensity for fracture from the pure Griffith value.  ...  Recently, the effect of dislocation blocking on crack-tip behavior of a-Fe was studied using both atomistic and dislocation dynamics simulations [10] .  ... 
doi:10.1016/j.jnucmat.2004.04.266 fatcat:63gy2khkkjbpvpahb5mgwzaqym

Atomistic modeling of mechanical behavior

Ju Li, Alfonso H.W. Ngan, Peter Gumbsch
2003 Acta Materialia  
New discoveries are often made in the "virtual atoms labs". There, one has perfect control of the simulation conditions, and the amount of detailed atomistic information is often breathtaking.  ...  We present progresses in the theory and computation of ideal strength, dislocations activation processes and brittle fracture from the atomic perspective, in close connection with experiments and other  ...  Similarly, for the dynamic fracture issues, nice and detailed experiments are available on silicon single crystals which could in the combination with appropriate atomistic modeling lend themselves well  ... 
doi:10.1016/j.actamat.2003.08.002 fatcat:etwsxqcsdfcsxp2qhiax32k43q
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