Lock-in Thermography Image Procesing
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چکیده
Composite materials have appropriate thermal properties for detection flaws by means of non-destructive infrared thermography methods. Infrared thermography methods are based on tracking heat flow that has been induced by flood lamps. Lock-in thermography, as one of infrared thermography methods, is used in detection of flaws. Surface of specimen is periodically heated by heat flow in form of sinusoid. Presented method enables reconstruction of sinusoid wave after reflection from defect boundaries. Parameters of reconstructed heat wave differ for waves reflected from non-damaged and damaged material. The period of excitation is varied. In the presented article a basic theory of lock-in thermography and signal processing is given. The lock-in method is applied on samples made of carbon fibers reinforced plastic in order to show possibilities of
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