Non-Destructive Testing by Means of Frequency Modulated Infrared Imaging

Infrared non-destructive evaluation (IRNDE) is an emerging approach for non-contact inspection of various solid materials such as metals, composites and semiconductors for industrial and research interest. This paper describes the characterization of possible subsurface failures inside Mild steel materials, which are widely used, particularly in the power and steel industries by Frequency Modulated Thermal Wave Imaging(FMTWI). Mild steel specimens with a man made defects were tested by of recently proposed pulse compression based approach. Present work highlights comparative results obtained with both phase and correlation based approaches for defect detection using frequency modulated thermal excitation scheme.