The peculiarities of magnetic and eddy-current testing of quenched structural steel hardened by nanostructuring frictional treatment

Abstract

This paper deals with the study of the potential of the magnetic and eddy-current methods for the assessment of the structural state of hardened wear-resistant layers on the surface of quenched medium-carbon structural steel 50 (0.51 wt % C) that is subjected to frictional treatment by a sliding hemispherical hard-alloy indenter. It is found that the presence of a thin ∼220 μm hardened wear-resistant layer on the surface of quenched steel 50 can be verified by readings of an eddy-current instrument, as well as by values of the coercive force (for major and minor magnetic hysteresis loops) and the residual magnetic induction (for minor magnetic hysteresis loops if measurements are carried out in weak magnetic fields). The eddy-current method has the highest susceptibility to the structural transformations caused by frictional treatment. © 2012 Pleiades Publishing, Ltd.