Magnetic Nondestructive Investigation of Ferromagnetic Alloys Subjected to Stress and Fatigue

Abstract

High depth nondestructive stress measurements on thick steel alloysABSTRACT. The influence of stress and fatigue under various stress amplitudes on the magnetic properties of a range of magnetic alloys (Ni, Fe 55 Ni 45 , Fe 64 Ni 36 and Fe 54 Ni 29 Co 17 ) was studied. Barkhausen effect signal and symmetrical minor hysteresis loops were measured at various stages during the tensile and fatigue tests. The data were analyzed using the Preisach model formalism in order to identify parameters which better described the structural changes in the materials. The results obtained from this work has enhanced the applicability of magnetic measurements for non-destructive testing of materials.