Annealing behaviour of reactor pressure-vessel steels studied by positron-annihilation spectroscopy, Mossbauer spectroscopy and transmission electronmicroscopy
V. Slugen et al., Annealing behaviour of reactor pressure-vessel steels studied by positron-annihilation spectroscopy, Mossbauer spectroscopy and transmission electronmicroscopy, J NUCL MAT, 274(3), 1999, pp. 273-286
The annealing behaviour of commonly used reactor pressure-vessel steels was
studied using positron-annihilation spectroscopy (PAS) (lifetime and Doppl
er broadening techniques), transmission Mossbauer spectroscopy (MS), integr
al low-energy electron MS (ILEEMS) and transmission electron microscopy (TE
M). The results of these methods applied to different types of steels are d
iscussed. Some significant differences in the experimental results are obse
rved between the Russian (3 types) and Western Europe (5 types) steels and
between individual specimens within these two groups. All specimens were an
nealed in vacuum and studied after this thermal treatment. It was confirmed
that the heat affected zone (HAZ) is the most sensitive region for thermal
and neutron irradiation-induced embrittlement in the reactor. Positron-ann
ihilation lifetime measurements on HAZ specimens annealed at successively h
igher temperatures show the drastic increase in the vacancy-type defect for
mation between 525 degrees C and 600 degrees C. Therefore these specimens w
ere selected for further detailed studies by TEM. (C) 1999 Elsevier Science
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