The surface weak magnetic signals of low carbon steel under cyclic loads

The magnetization induced by applied cyclic stresses on low carbon steel samples was studied through experiments by using a high sensitive magnetic sensor. The stress-magnetic coupling under cyclic tensile stress was researched during static, cyclic and fatigue loading process respectively. The results indicate the consistency and also some contradiction with existing conclusions of metal magnetic memory theory or magneto-mechanical researches. It is put forward that the stress induce magnetization is dependent on both applied stress and micro structure abnormality in ferromagnetic materials. Then the potential applications of the stress-magnetic coupling behavior were proposed.