TY - JOUR
T1 - TEM investigation of long-term annealed highly irradiated beryllium
AU - Van Renterghem, Wouter
AU - Leenaers, Ann
AU - Van den Berghe, Sven
N1 - Score = 10
PY - 2008/2
Y1 - 2008/2
N2 - Beryllium, irradiated at around 50 °C for 15 years up to a fast neutron fluence (>1 MeV) of 4.67 · 1022 n cm², was annealed at temperatures
of 500, 750, 825 and 900 °C. In a previous study, the influence of the annealing temperature and time on the He content and the
microstructure was investigated with optical and scanning electron microscopy. To complement the observations made, transmission
electron microscopy measurements on the same set of specimens were conducted to determine the helium behaviour at nanometer scale.
It was found that the as-irradiated material is heavily stressed and contains many dislocation loops. In the samples annealed at 500 and
750 °C, these dislocation loops disappeared and a large number of small faceted bubbles have formed inside the grains. Close to grain
boundaries, a bubble-free area was observed. Annealing at 825 and 900 °C results in the complete removal of all small bubbles, and the
local defect structure reverts back to the one of the un-irradiated material.
AB - Beryllium, irradiated at around 50 °C for 15 years up to a fast neutron fluence (>1 MeV) of 4.67 · 1022 n cm², was annealed at temperatures
of 500, 750, 825 and 900 °C. In a previous study, the influence of the annealing temperature and time on the He content and the
microstructure was investigated with optical and scanning electron microscopy. To complement the observations made, transmission
electron microscopy measurements on the same set of specimens were conducted to determine the helium behaviour at nanometer scale.
It was found that the as-irradiated material is heavily stressed and contains many dislocation loops. In the samples annealed at 500 and
750 °C, these dislocation loops disappeared and a large number of small faceted bubbles have formed inside the grains. Close to grain
boundaries, a bubble-free area was observed. Annealing at 825 and 900 °C results in the complete removal of all small bubbles, and the
local defect structure reverts back to the one of the un-irradiated material.
KW - Beryllium
KW - TEM
KW - Helium bubbles
UR - http://ecm.sckcen.be/OTCS/llisapi.dll/open/ezp_86327
UR - http://knowledgecentre.sckcen.be/so2/bibref/4767
U2 - 10.1016/j.jnucmat.2007.07.007
DO - 10.1016/j.jnucmat.2007.07.007
M3 - Article
SN - 0022-3115
VL - 374
SP - 54
EP - 60
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
IS - 1-2
ER -