SYMPOSIA PAPER Published: 01 January 1996
STP16472S

Research to Understand the Embrittlement Behavior of Yankee/BR3 Surveillance Plate and Other Outlier RPV Steels

Source

The reactor pressure vessels at the Yankee Rowe and Belgian BR3 nuclear plants were constructed by Babcock & Wilcox in 1958. The plates of an open-hearth fabrication were welded using a submerged-arc process with Linde 80 flux as the filler. The original surveillance programs at the two plants were limited to representative A302B specimens; they feature similar chemistries as the ASTM reference plate, but coarser microstructure. The present testing program includes sixteen Charpy-V and four tensile specimens of the surveillance plate, irradiated at BR3 at a dose rate of ≈ 7 E10 cm−2.s−1 (>1MeV) over a period of 25 years; the investigation also addresses annealing and notch orientation effects. The new experimental results are compared to previously published data for the same and/or related melts. The Yankee/BR3 surveillance plate displays an anomalously large 41J Cv-shift as compared to the ASTM reference plate and to Regulatory predictions. Some of the Linde 80 welds investigated by the BR3 program are also found to behave as outliers. The data are evaluated in the light of state-of-the-art damage modeling and fracture micro-mechanics concepts, which are currently being incorporated into a new, consolidated strategy for improved RPV surveillance. The approach makes extensive use of the information contained in the load-deflection response of the instrumented Cv test. The implications of such analysis in terms of RPV steel embrittlement trend curve development are discussed.

Author Information

Fabry, A
, Mol, Belgium
Van de Velde, J
, Mol, Belgium
Puzzolante, JL
, Mol, Belgium
Van Ransbeeck, T
, Mol, Belgium
Verstrepen, A
, Mol, Belgium
Biemller, EC
Yankee Atomic Electric Company, Bolton, USA
Carter, RG
Electric Power Research Institute, Charlotte, USA
Petrova, T
INRNE, Sofia, Bulgaria
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Developed by Committee: E10
Pages: 138–187
DOI: 10.1520/STP16472S
ISBN-EB: 978-0-8031-5328-8
ISBN-13: 978-0-8031-2016-7