Three-Dimensional Pulse Compression for Infrared Nondestructive Testing

Abstract

This letter proposes an optimal nondestructive subsurface defect detection method to investigate the capabilities of the infrared thermography through a finite-element analysis-based model. A finite-element analysis (FEA) software was used to generate models and analysis was carried out using MATLAB software. Pulse compression approach has been introduced for subsurface defect detection and its advantages and limitations are compared with existing phase approach-based thermography. Investigations has been carried out on a simulated plain carbon steel specimen with a flat bottom hole defects at various depths of different diameters is introduced. Comparison has been made with the conventional phase-based techniques.

Depth Retrieval Procedures in Pulsed Thermography: Remarks in Time and Frequency Domain Analyses

“…Moreover, based on this preliminary study, the application of quantitative infrared thermography for depth prediction in different materials and/or for the characterisation of different defects would provide a clearer view in the assessment of these depth prediction methods. In this direction, a comparative study incorporating different methodologies for depth prediction, such as the Logarithmic Peak Second-Derivative Time method [41], techniques based on the development of numerical modelling [42], or the recently developed Pulse Compression Thermography [43][44][45], which has shown to provide results with enhanced SNR, can define more representatively the strengths and weaknesses of each quantitative technique. −11.5 …”

Non-Destructive Evaluation of Concrete Structures by Non-Stationary Thermal Wave Imaging

“…Pulse compression technique prevalent in RADAR allows the transmission of a medium peak power, long duration modulated wave to improve the target detection range and resolution comparable to that achieved with a short duration high peak power pulsed based techniques [11,12,14]. This can be achieved with a correlation based pulse compression technique by cross correlation of the temporal temperature distribution over the chosen reference pixel s (t) over the sample, with the time delayed attenuated version of the pixel h (t) for an imposed linear frequency modulated incident heat flux over the sample.…”

“…In active approach [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], external heat stimulus is provided to the test sample of whose thermal response is to be observed. Known characteristics of the external thermal stimulation applied onto the specimen (i.e., nature of excitation, its time duration and its band width etc), facilitates the qualitative and quantitative characterization of sub-surface defects.…”

“…Insight of the above mentioned advantages and limitations of the widely used conventional methods, this paper focuses on an experimental investigation for detection of corrosion of rebar in reinforced concrete structures by frequency modulated non-stationary thermal wave imaging [7][8][9][10][11][12][13][14][15][16][17][18].…”

The design of infrared non-destructive testing for investigation multi-layer materials

“…Detecting a characteristic of a possible defect in a shorter time and easier way are two notable benefit of infrared thermography [6]. This method can be applied in two different ways, namely active and passive thermography [7].…”