Qualitative subsurface analysis in quadratic frequency modulated thermal wave imaging

Abstract

From the Past decades Non Stationary Thermal Wave Imaging (NSTWI) is enlarging as reliable eminent technology to examine various materials like Reinforced polymers and coatings used in industrial applications like aerospace, mechanical, civil appliances etc. Testing of these materials prior to usage is a challenging task which makes use of Non Destructive Testing& Evaluation(NDT&E) techniques. Present article uses a chirped Quadratic Frequency Modulated Thermal Wave Imaging (QFMTWI) to test underneath the Carbon Fiber Reinforced Polymer (CFRP) specimen. Further various post processing methods are used to visualize the subsurface details. Signal to Noise Ratio (SNR) is used as a performance metric to evaluate the performance of various post processing approaches.