IMPROVED MODEL FOR PREDICTING J-R CURVES FROM CHARPY DATA

IT IS NECESSARY TO ESTIMATE J-R OR JI DATA FOR AGING AND RE-SIDUAL LIFE STUDIES, USING DATA FROM SURVEILLANCE CAPSULE SPECIMENS THAT REFLECT THE CURRENT STATE OF THE PRESSURE VESSEL STEEL. AN IMPROVED MODEL IS NEEDED THAT WILL PREDICT J J-R DATA FROM CHARPY DATA, TENSILE PROPERTIES, MATERIAL COM-POSITION AND OTHER MEASURABLE PROPERTIES. SUCH A MODEL WILLBE DEVELOPED UNDER THIS PROJECT, USING INNOVATIVE PATTERN RECOGNITION AND SURFACE-FITTING CODES TO IDENTIFY THE KEY PARAMETERS AND OPTIMAL MODELING FUNCTIONS. THE OBJECTIVES OF PHASE I ARE TO COLLECT READILY-AVAILABLE DATA, EVALUATE THE ADEQUACY OF THE DATABASE, AND DEMONSTRATE THE ABILITY OFTHE ADVANCED PATTERN RECOGNITION AND MODELING TOOLS TO PRO- DUCED A SUPERIOR MODEL. PHASE II WOULD REFINE AND VERIFY THE MODEL USING A MORE COMPREHENSIVE DATABASE, INCLUDING RE-SULTS OF EXPERIMENTS DESIGNED TO FILL IN GAPS IN THE DATA THAT WERE IDENTIFIED IN PHASE I.