Investigation of Structural Steel Damage by Nondestructive Testing

The paper presents the results of studying damage development stages in three structural steels (low-carbon, medium-carbon, and stainless) at different stages of fatigue failure by nondestructive testing methods. Acoustic, magnetic, and electrical parameters of the steels under study are measured during periodic test stops. By the behavior of the physical quantities, the stages of damage accumulation before sample failure are identified. Nondestructive testing parameters are proposed to characterize the transition from the penultimate stage to the last stage of damage evolution before fracture.