FRACTURE TOUGHNESS TESTING OF LINDE 1092 REACTOR VESSEL WELDS IN THE TRANSITION RANGE USING CHARPY-SIZED SPECIMENS

摘要

The present reference toughness method for predicting the change in fracture toughness can provide over estimates of these values because of uncertainties in initial RT_(NDT) and shift correlations. It would be preferable to directly measure fracture toughness. However, until recently, no standard method was available to characterize fracture toughness in the transition range. ASTM E08 has developed a draft standard that shows promise for providing lower bound transition range fracture toughness using the master curve approach. This method has been successfully implemented using 1T compact fracture specimens. Combustion Engineering reactor vessel surveillance programs do not have compact fracture specimens. Therefore, the CE Owners Group developed a program to validate the master curve method for Charpy-sized and reconstituted Charpy-sized specimens for future application on irradiated specimens. This method was validated for Linde 1092 welds using unirradiated Charpy-sized and reconstituted Charpy-sized specimens by comparison of results with those from compact fracture specimens.