Radiation annealing mechanisms of low-alloy reactor pressure vessel steels dependent on irradiation temperature and neutron fluence

Journal Article · Wed Dec 01 04:00:00 EST 1982 · Nucl. Technol.; (United States)

OSTI ID:7071154

Pachur, D

Heat treatment after irradiation of reactor pressure vessel steels showed annealing of irradiation embrittlement. Depending on the irradiation temperature, the embrittlement started to anneal at about 220/sup 0/C and was completely annealed at 500/sup 0/C with 4 h of annealing time. The annealing behavior was normally measured in terms of the Vickers hardness increase produced by irradiation relative to the initial hardness as a function of the annealing temperature. Annealing results of other mechanical properties correspond to hardness results. During annealing, various recovery mechanisms occur in different temperature ranges. These are characterized by activation energies from 1.5 to 2.1 eV. The individual mechanisms were determined by the different time dependencies at various temperatures. The relative contributions of the mechanisms showed a neutron fluence dependence, with the lower activation energy mechanisms being predominant at low fluence and vice versa. In the temperature range where partial annealing of a mechanism took place during irradiation, an increase in activation energy was observed. Trend curves for the increase in transition temperature with irradiation, for the relative increase of Vickers hardness and yield strength, and for the relative decrease of Charpy-V upper shelf energy are interpreted by the behavior of different mechanisms.

• Research Organization: Kernforschungsanlage Julich Postfach 1913, 5170 Julich
• OSTI ID: 7071154
• Journal Information: Nucl. Technol.; (United States), Journal Name: Nucl. Technol.; (United States) Vol. 59:3; ISSN NUTYB
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220200* -- Nuclear Reactor Technology-- Components & Accessories
36 MATERIALS SCIENCE
360106 -- Metals & Alloys-- Radiation Effects
ACTIVATION ENERGY
ALLOYS
ANNEALING
CONTAINERS
DAMAGING NEUTRON FLUENCE
EMBRITTLEMENT
ENERGY
ENERGY RANGE
EV RANGE
EV RANGE 01-10
HEAT TREATMENTS
HIGH TEMPERATURE
IRON ALLOYS
IRON BASE ALLOYS
IRRADIATION
MATERIALS
MECHANICAL PROPERTIES
NEUTRON FLUENCE
PHYSICAL PROPERTIES
PHYSICAL RADIATION EFFECTS
POST-IRRADIATION EXAMINATION
PRESSURE VESSELS
RADIATION EFFECTS
REACTOR MATERIALS
STEELS
TEMPERATURE DEPENDENCE
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
VICKERS HARDNESS