Infrared Thermal Wave Imaging for Nondestructive Testing of Fibre Reinforced Polymers

Abstract

Among various widely used InfraRed Thermal NonDestructive Testing (IRTNDT) modalities, Non-Stationary Thermal Wave Imaging (NSTWI) techniques have proved to be an indispensable approach for the inspection and evaluation of various materials. Growing concern for the development of surface and subsurface defect detection techniques with moderate peak power heat sources (than the widely used conventional pulse based thermographic methods) and in a reasonably less testing time (compared to sinusoidal modulated lock-in thermography), makes these NSTWI techniques invaluable for this field. The present work highlights a comparative study on various NSTWI techniques, further experimental results are presented to find their defect detection capabilities by taking signal to noise ratio (SNR) into consideration.

Development and Application of Infrared Thermography Non-Destructive Testing Techniques

“…This technique was originally used in military applications but is widely implemented in power equipment detection, petrochemical pipeline leakage detection, smelting temperature and lining damage detection, aviation cementing material quality detection, landslide monitoring and forecasting, medical diagnosis, and other fields. Research and application of this technology for non-destructive testing have also been introduced for defect detection, identification of material thermophysical parameters, internal structural damage detection, building energy savings analysis, and house quality assessment [ 119 , 120 , 121 , 122 , 123 , 124 , 125 , 126 , 127 , 128 , 129 ].…”

Detection and Characterization of Mechanical Impact Damage Within Multi-Layer Carbon Fiber Reinforced Polymer (CFRP) Laminate Using Passive Thermography

“…With the development of optoelectronic technology, infrared thermography is viewed as a promising nondestructive detection method due to the advantages of high-speed, non-contact, large area inspection and visual results etc., which contains two approaches [10], [11]: active and passive during the thermography detections. In the active thermography detection, an external controllable stimulation source such as high energy pulse flash [12], power ultrasonic transducer [13], lock-in [14], [15], eddy current induced heating [16], microwave [17] and laser [18] is needed and applied to stimulate the thermal contrast of object. For this reason active thermography is generally used to detect the structures in the maintenance process as well as the detection methods described in [3]- [6], not suitable for the real-time detection.…”

Infrared thermography for detection and evaluation of bone density variations by non-stationary thermal wave imaging

“…In general IRT can be implemented either in active or in passive approach [10]. In active mode, an external thermal stimulus (heating or cooling) is needed to produce significant thermal contrasts for the detection of subsurface variations and abnormalities located deep inside [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24]. However, in passive approach mapping of the thermal profile is carried out in the absence of any external stimulus [10].…”

“…Unlike, conventional pulse based (PT and PPT) or modulated (LT) thermographic techniques, the proposed scheme makes use of probing thermal waves into the test specimen within a desired band of frequencies of equal magnitude. This improves test resolution and sensitivity for identifying the sub-surface abnormalities in a single experimentation cycle with the use of medium peak power heat sources [15][16][17][18][19][20][21][22][23][24]. Active infrared thermographic techniques are equally applicable to medical imaging implementations for testing and evaluation of biomaterials.…”