Modeling incipient creep damage effects on Barkhausen noise and magnetoacoustic emission

Microscopic impact of creep damage incipience and development on the magnetic properties of ferromagnetic Cr–Mo steel

“…The microstructure of sample s3 does not exhibit many voids at grain boundaries, which means that the exploited tubes are in incipient stages of creep damage [7]. The question about the impact of precipitate microstructure on MAE intensity decrease of creep-damaged boiler tubes is under discussion [8,9]. The correlation between MAE and magnetostriction shown in Fig.…”

“…The first hypothesis was used in Ref. [9] in order to fit formally the decrease of MAE intensity. The model proposed in Ref.…”

“…The model proposed in Ref. [9] assumed that MAE intensity is proportional to average pinning-site density, which is inversely proportional to the average distance between DW-pinning centers (D parameter in this paper). In Ref.…”

“…In Ref. [9], this parameter was chosen arbitrarily. Now we apply a similar model in a different way.…”

“…Experimental values of MAE intensity (open circles) are plotted as a function of formal parameter n, which denotes some argument for dependence D(n). The n describes formally the creep damage process stage [9]. We construct this function knowing the ratio of Ia(s0) to Ia(s3) at n ¼ 7, and assuming that this ratio is equal to 1 at n ¼ 1 (at initial stage).…”