Ultrasonic and Eddy-Current Fatigue Monitoring of Austenitic Steel Welded Joints

Abstract We investigated the process of fatigue damage in welded joints made of austenitic steel by ultrasonic and eddy current types of testing. The development of an inhomogeneity in the distribution of the acoustic anisotropy parameter in the heat-affected zone and in the base material was studied. As a result of eddy current testing, the difference in the intensity of changes in the phase composition in the heat-affected zone and in the base material is shown. A linear relationship is obtained between the amplitude of the cycle deformation under regular loading in the low-cycle fatigue region and the critical value of the percentage of the magnetic phase in the base material. A method is proposed for assessing the fatigue damage to the material of welded joints in the heat-affected zone based on the results of eddy current testing.