Some patterns of magnetic noises electromotive force (EMF) -Barkhausen effect - depending on change of ferromagnetic materials strength characteristics, static loading conditions and level of plastic deformation with the purpose of this factor usage enhancement for mechanic hardening non-destructive control, have been studied. Practicability of EMF and magnetic noises usage in order to control the stated factors and their place among other methods of nondestructive control was evaluated. By methods of non-destructive control the impact of Barkhausen effect patterns on value and sign (strain - compression) of static loading in elastic and elasto-plastic domain for 65G and 38CrSi steel was studied. The character of graded magnetic noises EMF change at compression differs from the same change at strain, and that is evidence of magnetic noises method sensitivity to deformation sign. The experimental research results of correlation dependencies between characteristics laser-hardened near-surface cast-iron layers with lamellar graphite grains and factors Barkhausen effect have been quoted. Correlation between laser-hardening depth, that is determined metallographically, and the value of graded magnetic noises EMF has been stated, and that permits to use the results of these measurements for laser-hardening depth non-destructive control on important parts of diesels and similar plants.
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