Simulation study on sequential image features of eddy current stimulated thermography for NDT

摘要

Eddy current (EC) stimulated thermography, which is one of the electromagnetic nondestructive testing (NDT) methods combining EC and thermographic NDT techniques, has been paid more and more attentions in recent years and was proved to be efficient to some extent for detecting surface and subsurface defects in ferritic and non-ferritic materials. Images captured by an infra camera contain features referring to defect parameter while inspecting a conduct material with EC NDT method. In this paper, the sequential features of the IR images are focused on. EC stimulated thermography is introduced at the beginning of this paper. After that, it has been outlined that the theoretical basis of EC stimulated thermography for inspecting defects. And then, a simulation experiment study has been conducted on crack detection with EC stimulated thermography. Sequential images are obtained during the heating and cooling period of the test process. The sequential features have been analysed by the aid of feature extracting using Matlab toolbox.