s NonDestructive Evaluation of Carbon Fiber Reinforced Polymers with Ultrasonics and Infrared Thermography: An Overview on Historical Steps and Patents

The increasing use of composites in the transport industry and specifically in the aerospace field calls for nondestructive evaluation techniques for quality control during manufacturing and in service. Therefore, the availability of techniques which are effective to assess a material is free of slag inclusions, delamination and porosity is a crucial point. Of course, no technique is exhaustive alone; some are more effective for detection of surface discontinuities, others for outlining of buried shallow defects and others for detection of deeper anomalies. Then, an integration of two, or more, techniques may be the optimal solution especially for nondestructive evaluation of aerospace parts. The attention of this review is focused on two techniques: ultrasonic testing, which is commonly used, and infrared thermography, which was recently recognized amongst standards, for nondestructive testing and evaluation of composite materials in the aeronautical industry. For each of the two techniques, historical steps are traced with particular attention to the patents produced. In particular, the advantages coming from an integration of infrared thermography with ultrasonics and some other techniques are also discussed.