• Kumar Anubhav Tiwari Ultrasound Institute, Kaunas University of Technology, Kaunas
  • Renaldas Raisutis Ultrasound Institute, Kaunas University of Technology, Kaunas
Keywords: ultrasonic, defects, non-contact, composite materials, laser


There are various ultrasonic systems, developed for the effective testing and estimation of defect parameters in composite materials. Non-contact ultrasonic testing has already achieved significance over traditional contact methods that require coupling of media and are not well suited for the transmission of surface acoustic waves (SAW), which can cover a large area of structure under investigation. This paper compares approaches of air-coupled transmission/reception, laser ultrasonic, and electromagnetic acoustic transducer (EMAT), for testing and verification of composites and defect estimation in remote areas. It reviews the various practical applications. The study found the hybrid solution, consisting of the laser system as a transmitter and the air-coupled method as a detector, is the best among all.


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