非破壊手法による鋳造2相ステンレス鋼の熱時効評価(<小特集>実験計測技術の新展開)

概要

論文の詳細を見る
Cast duplex stainless steel is frequently used in main coolant pipes and reactor coolant pump casings of nuclear power plants due to its excellent material strength, toughness and superior corrosion resistance. However, it is known that material deterioration referred to as thermal aging occurs when this material is exposed to high temperature over 300℃ for a long time. As a result, the material toughness decreases. Therefore in managing the components made of the cast duplex stainless steel, it is necessary to evaluate non-destructively the change in the mechanical property caused by thermal aging. In this study, to develop a non-destructive technique for evaluating the deterioration of toughness in cast duplex stainless steel caused by thermal aging, we compared 5 kinds of evaluation techniques, ultrasonic sound velocity measurement, thermoelectric power measurement, resistivity measurement, SQUlD (Superconducting Quantum Interference Device) measurement and positron annihilation line-shape analysis for detecting ability of thermal aging. As a result, the thermoelectric power measurement is the most effective technique for evaluating thermal aging of duplex stainless steel because of the closest correlation between non-destructive parameter and toughness and because of low deviation of measured values.
社団法人日本機械学会の論文
2001-03-25