Simulation study on quantitative evaluation of crack depth in crack inspection with eddy current stimulated thermography

Quantitative evaluation of cracks is the critical issue of eddy current stimulated thermography. In this paper, numerical simulation study on the quantitative evaluation of cracks with eddy current stimulated thermography is introduced. The simulation works are conducted using COMSOL software. Sequential images are obtained during the heating and cooling periods of the test process. By processing the images with Matlab toolbox, the features of temperature distribution on the samples with specific artificial crack were extracted. A form of the temperature history of the centre point of the cracks have been constructed with the simulation results which is applied to quantitate the crack parameters by Lagrange interpolation algorithm with the temperature at the surface centre point of the crack obtained from the infrared image. The simulation results show that the crack depth can be calculated with the form of crack temperature history.