NON-DESTRUCTIVE ESTIMATION METHOD OF CREEP STRAIN QUANTITY OF HEAT-RESISTING STEEL

摘要

PROBLEM TO BE SOLVED: To provide a non-destructive estimation method capable of estimating creep strain quantity in a non-destructive manner even with respect to heat- resisting steel having an annealed martensite structure like improved 9Cr steel (ASME Standard SA387Cr91). SOLUTION: The positive electron annihilation measurement of the part to be measured of a sample is performed and the ratio of the count number of the peak central part of the energy distribution ofγ-rays based on the positive electron annihilation measurement is calculated as an S-parameter and this S-parameter is compared with the relation of the S-parameter to the preliminarily calculated known creep strain quantity of the same composition material. By this constitution, the creep strain quantity of heat-resisting steel receiving creep damage can be estimated in a non-destructive manner and measurement on the spot also becomes possible.