Use of Eddy-Current Method for Determining the Thickness of Induction-Hardened Layer in Cast Iron

Journal: Metal Science and Heat Treatment

Publication date: 30 November 2013

Abstract:

Cast iron with globular graphite is studied after surface induction hardening. Hardness profiles of iron bars are plotted for determining the thickness of the hardened layer. Relations between the thickness of the hardened layer and the output voltage are obtained by the method of dual frequency (induced voltage and normalized impedance) for checking the applicability of the eddy current method. The correlation coefficient and the error of the evaluation of the thickness of the hardened layer are determined with the help of the relations obtained.