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As a result of this work, it is now possible to quantify how nanobubble behaviour changes within different materials, and under different plasma conditions.

The data indicate that deuterium trapping in tungsten cannot be explained
without cluster or nano - bubble formation . Cluster trapping appears to depend
on the concentration and type of cluster nucleation sites , including impurities ...

First, one can assume that the seeds for helium nano-bubble nucleation are
formed by the pre-existing lattice defects. ... nano-bubble produces seeds for
nucleation of another nano-bubble), which makes the final evolution of the
formation of the helium nano-bubble ... to the surface, which is observed in MD
simulations at some orientations of the tungsten crystal [69], inhibits deeper
penetration of helium.

Kinetic Monte Carlo simulations of helium cluster nucleation in tungsten with
preexisting vacancies. Fusion ... Thermal stability of helium-vacancy clusters and
bubble formation – Multiscale modeling approach for fusion materials
development. ... Radiation resistance of nano-crystalline iron: Coupling of the
fundamental segregation process and the annihilation of interstitials and
vacancies near the grain ...

Modeling suggests that helium bubbles increase pressure in the W above the
threshold where prismatic loop punching occurs, ... plasma species, ie, deuterium
, helium, and beryllium, suggests that the presence of beryllium may suppress
nano-bubble formation [70]. ... wall) without wall conditioning, but these had poor
Figure 3.15 A secondary electron microscope image of a tungsten Plasma
exhaust 49.

These particles had mean diameters between 0.36 and 0.62 nm. Pisces-A exposed samples showed more complex patterns, which may suggest the formation of faceted nano-bubbles or nano-scale surface structures.

We report on the formation of microvoids in tungsten and silicon , and the re -
filling of the voids with helium and ... from the bubbles by permeation , exactly as
was shown some ten years ago by us for nano - size helium bubbles in silicon [ 2
] .

Tungsten helium irradiation effects Verifying the robustness of ITER'S PFCs
armoured with W Understanding the role of ... Of concern are bubble and ' fuzz '
include surface modifications from ion and neutron damage formation under He
ion ...

... the recombination of vacancies and interstitial atoms / ions with potential pore
formation ; the formation of helium - via the reaction involving hydrogen and its
relatives , however , the yield is very low – which in its gaseous form can be a
source of nano or micro - bubbles . ... We have also estimated the impact of an
internal ( 10 um ) tungsten cladding coating ( chemical or physical vapour
deposition ) on ...

Nano - scaled bubbles ( cavity diameter < 5 nm ) were observed densely , and
with increasing displacement dose ... 8 presents dislocation image of the same
set of network formation through unfaulting and loop - loop interVoid Diameter , D
 ...