COMPARISON OF SELECTED METHODS FOR NON-DESTRUCTIVE EVALUATION OF STRUCTURAL DEGRADATION OF CONSTRUCTIONAL FERROMAGNETIC MATERIALS

Elemír Ušák

   In this study, two advanced methods out of several utilised for nondestructive inspection of ferromagnetic constructional materials were compared. Already well-established, yet novel method, Magnetic Adaptive Testing (MAT), was put into the con-frontation with brand new approach based on examination of the relaxation phenomena associated with domain wall motion. Early experiments have revealed that in case of the samples made of standard steels subjected to long-term annealing MAT sometimes brings ambiguous, chaotic results very difficult to interpret, whereas the relaxation processes appear to correlate strongly and in a simple manner with annealing time acting as an agent representing artificial ageing of material. Hence the de-tailed analysis of relaxation processes seems to be a new, promising way for non-destructive inspection of structural degradation of this type of materials even when MAT fails. Thus, the offer of magnetic non-destructive evaluation methods for industrial practice extends.

Keywords: non-destructive evaluation, structural degradation, ferromagnetic constructional materials

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