Depth measurement using infrared thermography

Infrared Thermography is a Nondestructive Testing and Evaluating (NDT&E) technique. it is an effective technique for quantitative prediction of defect depth and defect area, an analysis of depth measurement based on theoretical one-dimensional solution of pulsed thermography is used, assuring the depth of defects by calculating break time that the Logarithmic time evolution of the health area begins to deviate from that of the defective area. Several back-drilled flat-bottom holes which located at three different depths in the aluminum plate are used as simulated defects. Meanwhile, other two coating samples buried with nine defects are also detected. The experimental results of the infrared thermography can demonstrate the capability to predict the depth of defects. The advantages and disadvantages of this method are also outlined. © 2009 SPIE.