Notch Ductility Degradation of Low Alloy Steels with Low-to-Intermediate Neutron Fluence Exposures.
Abstract
The extent and trend of Charpy-V (C sub v) notch ductility changes in reactor vessel materials with fluences of 1 X 10 (TO THE 18TH POWER) TO 10 X 10 (to the 18th power) n/square cm greater than 1 MeV were investigated with several thick section steel plates and submerged arc weld deposits irradiated at 288C (550 F). The materials were fully representative of reactor vessels now in service and had copper contents ranging from 0.10 to 0.40% and phosphorus contents ranging from 0.008 to 0.020%. Material irradiations were performed in a 2 MW pool reactor. The steels with high radiation sensitivity indicated an onset of notch ductility change at fluences of approximately 1.5 x 10 (to the 18th power) n/square cm by an elevation in the ductile-to-brittle transition temperature. Reductions in upper shelf were not observed at this fluence level but were in the range of 0 to 15% at approximately 4 x 10 (to the 18th power) n/square cm and between 15 to 44% at approximately 8 x 10 (to the 18th power) n/square cm. The data trend suggests a power law relationship of upper shelf reduction to fluence at low-to-intermediate fluences. The C sub v transition temperature elevation and upper shelf reduction with irradiation are compared to embrittlement projections by U.S. Nuclear Regulatory Commission Guide 1.99. A limited experimental comparison of radiation effects to dynamic fracture toughness and notch ductility is also presented. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 14, 1980
- Accession Number
- ADA081003
Entities
People
- J. Russell Hawthorne
Organizations
- United States Naval Research Laboratory