Mathematical modelling of the Eddy current and its application to the material examinations

Abstract

Eddy Current testing, especially the Preventive Multi-Frequency Testing (PMFT) method is being used on C45R steel material, under the control of specialities like microstructure and stiffness characteristics.The physical principles of eddy current is examined theorically, and the applications of the procedure are shown experimentally. Eddy currents can easily be used in determination of heat treatment differences of forging steel. As heat treatment conditions change, microstructure and stiffness differences that can occur especially on surface and locations near the surface of components cause some changes in permeability particularly, in high test frequencies. Eddy current can outshine by causing big changes in bobbin impedance.

Keywords

• Eddy current, preventive multi-frequency testing (PMFT), inductive reactance, impedance plane

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