Analysis of the Irradiation Data for A302B and A533B Correlation Monitor Materials

摘要

The results of Charpy V-notch impact tests for A302B and A533B-1 Correlation Monitor Materials (CMM) listed in the surveillance power reactor data base (PR-EDB) and material test reactor data base (TR-EDB) are analyzed. The shift of the transition temperature at 30ft-lb is considered as the primary measure of radiation embrittlement in this report. The hyperbolic tengent fitting model and uncertainty of the fitting parameters for Charpy impact tests are presented in this report. For the surveillance CMM data, the transition temperature shifts at 30ft-lb generally follow the predictions provided by Revision 2 of Regulatory guide 1.99 (R.G. 1.99). Difference in capsule temperatures is likely explanation for large deviations from R.G. 1.99 prediction. Deviations from the R.G. 1.99 predictions are correlated to similar deviations for the accompanying materials in the same capsules, but large random fluctuations prevent precise quantitative determination. Significant scatter is noted in the surveillance data, some of which may be attributed to variations from one specimen set to another, or inherent in Charpy V-notch testing. In general, the embrittlement behavior of both the A302b and A533B-1 plate materials is similar. There is evidence for a fluence-rate effect in the CMM data irradiated in test reactors; thus its implication on power reactor surveillance programs deserves special attention.