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Radiation damage reduction by grain-boundary biased defect migration in nanocrystalline Cu
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Ultra-high strength and plasticity mediated by partial dislocations and defect networks: Part I: Texture effect
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Risk comparison for prenatal use of analgesics and selected birth defects, National Birth Defects Prevention Study 1997–2011
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Exciton dynamics in cation-exchanged CdSe/PbSe nanorods: The role of defects
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Visualizing MICP with X-ray μ-CT to enhance cement defect sealing
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Understanding the microstructures of triangular defects in 4H-SiC homoepitaxial
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Investigation of defect creation in GaP/Si(0 0 1) epitaxial structures
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Effect of Confinement of SIA Cluster Diffusion by Impurities on Radiation Defect Accumulation due to 14MeV neutrons in Tungsten
Impurities acting as traps, reduce the self-interstitial atom (SIA) cluster mobility, thereby increasing recombination and in turn enhancing radiation-resistance of polycrystalline materials. However, at elevated temperatures, depending on SIA-trap (impurity) binding energy, SIA clusters may trap and detrap (detach) numerous times. In tungsten, SIA clusters of all sizes glide one-dimensionally (1D) along their Burgers vector direction. Hence, detrapped SIAs would retrace their path, confining their 1D-glide between traps. However, small SIA clusters can change the direction of their 1D-glide by overcoming a rotation barrier. In addition, impurities or solutes are known to reduce this barrier. A lower rotation barrier can result in detrapped SIA clusters that diffuse in a random 1D direction, effectively leading to 3D (net-3D) diffusion. Here we investigate the effect of two cases of SIA diffusion, namely confined-1D diffusion and net-3D diffusion, on the damage accumulation in polycrystalline tungsten under 14 MeV neutron irradiation using the object kinetic Monte Carlo method. Simulations were performed using cascade debris obtained from molecular dynamics simulations with primary knock-on atom (PKA) energies corresponding to 14 MeV neutrons. In the simulations with net-3D diffusion, SIA clusters of all sizes diffuse in a random 1D direction after the clusters detrap. While for the confined 1D diffusion case, SIA clusters larger than size 5 retain their original direction of 1D-glide. In both types of simulations, trapped vacancies are assumed to be permanently immobilized. Unexpectedly, the damage accumulation was lower with confined 1D diffusion than that with net-3D. We present a systematic comparison of the influence of the two cases of SIA diffusion on the radiation damage accumulation as a function of dose rate, detrapping barrier, and impurity concentration at 1025 K.
Defects in local atomic structure of ZnO films sensitized with tinto and mangrove organic dyes
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Role of pre-existing point defects on primary damage production and amorphization in silicon carbide (β-SiC)
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Identifying flow defects in amorphous alloys using machine learning outlier detection methods
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