The Evolution of Structural Defects under Irradiation in W by Molecular Dynamics Simulation

Tungsten (W) can be used in plasma-facing components in a fusion reactor because of its excellent radiation resistance. Some studies have found that nanocrystalline metals with a high density of grain boundary show a higher ability to resist radiation damage compared to conventional coarse-grained materials. However, the interaction mechanism between grain boundary and defect is still unclear. In the present study, molecular dynamics simulations were carried out to explore the difference of defect evolution in single-crystal and bicrystal W, while the effects of temperature and the energy of the primary knocked atom (PKA) were taken into account. The irradiation process was simulated at the temperature range of 300 to 1500 K, and the PKA energy varied from 1 to 15 keV. The results show that the generation of defects is more sensitive to the energy of PKA than temperature; the number of defects increases at the thermal spike stage with the increase of the PKA energy, but the correlation with temperature is not strong. The presence of the grain boundary prevented the recombination of interstitial atoms and vacancies during the collision cascades, and the vacancies were more likely to form large clusters than interstitial atoms in the bicrystal models. This can be ascribed to the strong segregation tendency of the interstitial atoms to grain boundaries. The simulations provide useful information for understanding the role of grain boundaries in the evolution of irradiated structural defects.

[1]  Fei Gao,et al.  Displacement cascades database from molecular dynamic simulations in tungsten , 2023, Journal of Nuclear Materials.

[2]  Ruxin Zheng,et al.  Grain Boundary Migration as a Self-Healing Mechanism of Tungsten at High Temperature , 2022, Metals.

[3]  C. García-Rosales,et al.  Development of irradiation tolerant tungsten alloys for high temperature nuclear applications , 2022, Nuclear Fusion.

[4]  Fei Wang,et al.  Graphene distribution and structural integrity dependent irradiation resistance of graphene/tungsten composites , 2022, Materials Today Communications.

[5]  D. Perez,et al.  Interstitial hydrogen enhances the mobility of some grain boundaries in tungsten , 2022, Nuclear Fusion.

[6]  F. J. Domínguez-Gutiérrez,et al.  Temperature effects on the point defects formation in [111] W by neutron induced collision cascade , 2022, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms.

[7]  M. Čeh,et al.  Non-uniform He bubble formation in W/W2C composite: Experimental and ab-initio study , 2022, Acta Materialia.

[8]  D. Yun,et al.  The evolution of radiation-induced point defects near symmetrical tilt Σ5 (310) <001> grain boundary in pure δ-plutonium: A molecular dynamics study , 2020 .

[9]  Wan Fa-rong,et al.  Defect Production, Evolution and Thermal Recovery Mechanisms in Radiation Damaged Tungsten , 2020 .

[10]  H. Deng,et al.  Enhanced Radiation Tolerance of the Ni-Co-Cr-Fe High-Entropy Alloy as Revealed from Primary Damage , 2020, Acta Materialia.

[11]  Q. Hou,et al.  Molecular dynamics simulations of self-diffusion of adatoms on tungsten surfaces , 2019, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms.

[12]  Y. Shibuta,et al.  Interaction Between Nano-Voids and Migrating Grain Boundary by Molecular Dynamics Simulation , 2019, Acta Materialia.

[13]  Y. Shibuta,et al.  Atomistic Simulation of the Interaction Between Point Defects and Twin Boundary , 2018, physica status solidi (b).

[14]  Qurat-ul-ain Sahi,et al.  Primary radiation damage characterization of α-iron under irradiation temperature for various PKA energies , 2018 .

[15]  Y. Shibuta,et al.  Shear response of grain boundaries with metastable structures by molecular dynamics simulations , 2018 .

[16]  Y. Shibuta,et al.  Dynamic interaction between grain boundary and stacking fault tetrahedron , 2018 .

[17]  Cheng Lu,et al.  The formation and destruction of stacking fault tetrahedron in fcc metals: A molecular dynamics study , 2017 .

[18]  R. Abernethy.  Predicting the performance of tungsten in a fusion environment: a literature review , 2017 .

[19]  Makoto Fukuda,et al.  Neutron irradiation effects on the microstructural development of tungsten and tungsten alloys , 2016 .

[20]  S. Phillpot,et al.  MOLECULAR DYNAMICS SIMULATION OF INITIAL RADIATION DAMAGE IN TUNGSTEN , 2015 .

[21]  Z. Zeng,et al.  Primary radiation damage near grain boundary in bcc tungsten by molecular dynamics simulations , 2015 .

[22]  K. Nordlund,et al.  Radiation damage production in massive cascades initiated by fusion neutrons in tungsten , 2014 .

[23]  Z. Zeng,et al.  Transport, Dissociation and Rotation of Small Self-interstitial Atom Clusters in Tungsten , 2014 .

[24]  Lisa Ventelon,et al.  Interatomic potentials for modelling radiation defects and dislocations in tungsten , 2013, Journal of physics. Condensed matter : an Institute of Physics journal.

[25]  A. E. Sand,et al.  High-energy collision cascades in tungsten: Dislocation loops structure and clustering scaling laws , 2013, 1306.3824.

[26]  Zhongfu Zhou,et al.  In situ study of self-ion irradiation damage in W and W–5Re at 500 °C , 2013 .

[27]  A. Voter,et al.  Role of atomic structure on grain boundary-defect interactions in Cu , 2012 .

[28]  Xin Sun,et al.  Probing grain boundary sink strength at the nanoscale: Energetics and length scales of vacancy and interstitial absorption by grain boundaries in α -Fe , 2012 .

[29]  G. Bonny,et al.  The effect of prolonged irradiation on defect production and ordering in Fe–Cr and Fe–Ni alloys , 2011, Journal of physics. Condensed matter : an Institute of Physics journal.

[30]  G. Ackland.  Controlling Radiation Damage , 2010, Science.

[31]  Blas P. Uberuaga,et al.  Efficient Annealing of Radiation Damage Near Grain Boundaries via Interstitial Emission , 2010, Science.

[32]  Brian D. Wirth,et al.  Recent Developments in Irradiation-Resistant Steels , 2008 .

[33]  Na-Young Park,et al.  Molecular dynamics simulation of irradiation damage in tungsten , 2007 .

[34]  S. M. Corish,et al.  Radiation-induced amorphization resistance and radiation tolerance in structurally related oxides. , 2007, Nature materials.

[35]  R. Schäublin,et al.  Molecular dynamics simulation of radiation damage in bcc tungsten , 2007 .

[36]  Akira Suzuki,et al.  Coupling grain boundary motion to shear deformation , 2006 .

[37]  Roger E. Stoller,et al.  Subcascade formation in displacement cascade simulations: Implications for fusion reactor materials , 1999 .

[38]  M. Caturla,et al.  Defect production in collision cascades in elemental semiconductors and fcc metals , 1998 .

[39]  Brian D. Wirth,et al.  Primary damage formation in bcc iron , 1997 .

[40]  L. Mansur.  Theory and experimental background on dimensional changes in irradiated alloys , 1994 .

[41]  Steve Plimpton,et al.  Fast parallel algorithms for short-range molecular dynamics , 1993 .

[42]  S. Zinkle,et al.  Void swelling and defect cluster formation in reactor-irradiated copper☆ , 1989 .

[43]  W. Jäger,et al.  Formation of vacancy-type dislocation loops in tungsten bombarded by 60 keV Au ions , 1975 .

[44]  Qing-De Meng,et al.  Molecular dynamics simulations of temperature effect on tungsten sputtering yields under helium bombardment , 2017 .

[45]  Huijun Li,et al.  Recent progress in research on tungsten materials for nuclear fusion applications in Europe , 2013 .

[46]  A. Stukowski.  Modelling and Simulation in Materials Science and Engineering Visualization and analysis of atomistic simulation data with OVITO – the Open Visualization Tool , 2009 .

[47]  R. Stoller.  The role of cascade energy and temperature in primary defect formation in iron , 2000 .