Preliminary study on the mechanism of electromagnetic eddy current effect on non-conductive nano-composite materials

According to the electromagnetic induction principle, eddy current effect cannot be produced in non-conductive and non-magnetic materials. In this study, the eddy current effect of a non-conductive nano-compostie was investigated. Firstly, the nano-compostie was made by mixing nano Fe/FeSiB mixture in the plastic resin material. Secondly, the relationship between the excitation frequency and the eddy current testing sensitivity was obtained. Finally, the compare study on the eddy current testing sensitivity of the nano-composite, copper, iron and aluminum was carried out. The results show that eddy current effect can be produced in the non-conductive nano-compostie when the excitation frequency is beyond 50 KHz. There is no significant relationship between the excitation frequency and the eddy current testing sensitivity of the non-magnetic aluminum and copper. However, the eddy current testing sensitivity of magnetic pure iron and the nano-composite tends to decrease along with the decrease of the excitation frequency. This study can extend the eddy current testing to the non-conductive resinous material field.