Micromagnetic surface measurements for evaluation of surface modifications due to cyclic stress

The results of inspection fatigue damage by two magnetic nondestructive methods are presented. The magnetic hysteresis method can detect fatigue damage in the later stages of fatigue life. Magnetic Barkhausen signals, being highly sensitive to the surface condition of a material, show continuous change during the whole fatigue process. The Barkhausen effect measurement, aided by signal processing techniques, is therefore capable of monitoring surface modifications due to cyclic stress.<
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