Experimental assessments of Gundremmingen RPV archive material for fluence rate effects studies

Technical Report · Sat Oct 01 00:00:00 EDT 1988

OSTI ID:7065510

Hawthorne, J R; Hiser, A L

The 250-MW boiling water Gundremmingen reactor, KRB-A, in the Federal Republic of Germany (FRG) has been decommissioned by the utility owners. A joint USA/FRG/UK study, conceived by the US Nuclear Regulatory Commission (NRC), is underway to evaluate material removed from the vessel by trepanning for a critical assessment of power reactor vs. test reactor environment effects. MEA, Staatliche Material Pruefungsanstalt (MPA), and UKAEA-Harwell are responsible for the experimental phases of the joint program. The reactor vessel operated at /approximately/288/degree/C; the inner wall fluence estimate at the time of decommissioning was about 1 /times/ 10/sup 19/ n/cm/sup 2/, E > 1 MeV. This report describes irradiation assessments of a welded forging segment believed to be archive material from the KRB-A vessel fabrication. Preirradiation verification tests of the material are also summarized. Charpy-V (C/sub v/), compact tension (CT) and tension test specimens were irradiated in the 2-MW light water-cooled test reactor located at the Buffalo Materials Research Center. Five as-irradiated conditions and two postirradiation annealed conditions were evaluated. With 288/degree/C irradiations, the elevation in 100 MPa..sqrt..m temperature from fracture mechanics tests was found to match the elevation in 41-J temperature from C/sub v/ tests within 12/degree/C. The latter elevation was predicted well by NRC's Regulatory Guide 1.99. The L-C orientation for the archive material vs. the vessel trepans suggest a fluence-rate effect. The C-L orientation data, however, do not. A test orientation dependence of radiation embrittlement sensitivity, described by the trepan material but not the archive material, is responsible and is anomalous. 15 refs., 33 figs., 6 tabs.

• Research Organization: Nuclear Regulatory Commission, Washington, DC (USA). Div. of Engineering; Materials Engineering Associates, Inc., Lanham, MD (USA)
• OSTI ID: 7065510
• Report Number(s): NUREG/CR-5201; MEA-2286; ON: TI89001988
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
RWE-BAYERNWERK REACTOR
RADIATION EFFECTS
DAMAGING NEUTRON FLUENCE
EMBRITTLEMENT
NUMERICAL DATA
POST-IRRADIATION EXAMINATION
REACTOR DECOMMISSIONING
REACTOR DISMANTLING
REACTOR MATERIALS
BWR TYPE REACTORS
DATA
DECOMMISSIONING
DEMOLITION
ENRICHED URANIUM REACTORS
INFORMATION
MATERIALS
NEUTRON FLUENCE
POWER REACTORS
REACTORS
THERMAL REACTORS
WATER COOLED REACTORS
WATER MODERATED REACTORS
210100* - Power Reactors
Nonbreeding
Light-Water Moderated
Boiling Water Cooled