Defect detection in ceramic materials by quantitative infrared thermography
نویسنده
چکیده
In this paper infrared (IR) measurements and dedicated signal processing algorithms were developed and applied for defect detection on green ceramic tiles. Tiles with defects having known dimension and position were realized and tested by acquiring either heating and cooling transients of the tile subjected to thermal pulse excitation. As rarely defects appear directly in the thermal map, post-processing algorithms were used. Satisfactory results were achieved employing thermal tomography (TT), pulsed phase thermography (PPT), principal component analysis (PCA) and techniques of image balancing and trend removing. The performances of the different strategies were quantitatively compared in terms of contrast and signal-to-noise ratio.
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