Abstract
SUS304 steel is a kind of the austenitic stainless steel. It is used for various fields, example for the plant and the nuclear plant. The austenite phase is non-magnetism usually, but when SUS304 steel is received a big stress, a part of it is transformed into the martensitic phase that is ferromagnetism. In recently years, a lot of researches are done the nondestructive testing by measuring the magnetic characteri6stic using this character. It is hope that the method of detecting the damage before generation of the crack for to improve the safety of the machine and the structure. Then, we measured martensite fraction in the fatigue process of SUS304 steel, and we examined applicability from the change in martensite fraction to the fatigue damage evaluation in this study.
