THE DEPENDENCE OF MAGNETIC-PROPERTIES ON FATIGUE IU A533B NUCLEAR PRESSURE-VESSEL STEELS

Cyclic loading causes cumulative microstructural changes in materials, The magnetic properties of A533B steel are determined by both initial microstructures and microstructural changes induced by fatigue damage , From the results of a series of strain-controlled fatigue tests, the magnetic properties were found to change systematically with fatigue damage throughout the fatigue life. A linear relationship between magn etic remanence and mechanical modulus was observed. The fatigue lifeti mes were also dependent on the initial microstructure, and a relations hip between these lifetimes and pre-fatigue magnetic properties such a s coercivity was observed. Therefore this study has demonstrated that magnetic measurements can be exploited to evaluate the progress of fat igue damage in steel.