-
UKAEA-CCFE-PR(22)072022
Self-ion irradiation of pure tungsten with 2 MeV W ions provides a way of simulating microstructures generated by neutron irradiation in tungsten components of a fusion reactor. Electron microscopy has been used to characterize defects formed in tungsten samples by ion irradiation and estimate their density and size distribution. Some of the sample…
-
UKAEA-CCFE-PR(20)1132020
Combining spatially resolved X-ray Laue diffraction with atomic-scale simulations, we observe how ion-irradiated tungsten undergoes a series of non-linear structural transformations with increasing irradiation exposure. Nanoscale defect-induced deformations accumulating above 0.02 displacements per atom (dpa) lead to highly fluctuating strains at ~…
-
UKAEA-CCFE-PR(20)722020
Self-ion bombardment of pure tungsten with ion energies of 2 MeV is used to mimic the defects created by neutrons in a fusion reactor. Electron microscopy is used to characterize the microstructure of samples. Thermal Desorption Spectrometry (TDS) is performed on deuterium implanted samples in order to estimate deuterium inventory as function of…
-
UKAEA-CCFE-PR(20)1282019
It has been long hypothesized that the structure of a material bombarded by energetic particles might approach a certain asymptotic steady state in the limit of high exposure to irradiation. There is still no definitive verdict regarding the validity of this hypothesis or the conditions where it applies. To clarify this, we explore a highly simplif…
-
2014
Defect microstructures formed in ion-irradiated metals, for example iron or tungsten, often exhibit patterns of spatially ordered nano-scale dislocation loops. We show that such ordered dislocation loop structures may form spontaneously as a result of Brownian motion of loops, biased by the angular-dependent elastic interaction between the loops. P…
-
2011
Nanoscale prismatic loops are modeled via a partial stochastic differential equation that describes an overdamped continuum elastic string, with a view to describing both the internal and collective dynamics of the loop as a function of temperature. Within the framework of the Langevin equation, expressions are derived that relate the empirical par…
-
2010
In situ real-time electron microscope observations of metals irradiated with ultrahigh-energy electrons or energetic ions show that the dynamics of microstructural evolution in these materials is strongly influenced by long-range elastic interactions between mobile nanoscale radiation defects. Treating long-range interactions is also necessary for …
-
2009
The stability of interstitial defect and dislocation structures in bcc Fe as a function of temperature is believed to play a crucial role in determining defect evolution under irradiation conditions. The vibrational properties of defects constitute one contribution to the corresponding energetics and much work has been done within the harmonic appr…
-
2008
-
2007
We investigate the structure and mobility of single self-interstitial atom and vacancy defects in bodycentered- cubic transition metals forming groups 5B vanadium, niobium, and tantalum and 6B chromium, molybdenum, and tungsten of the Periodic Table. Density-functional calculations show that in all these metals the axially symmetric 111 self-inters…
Showing 1 - 10 of 10 UKAEA Paper Results
Page 1 of 1