27 октября, 2015 
Pokraskin In this method an ultrasound pulse is propagated through the entire structure and received by a second probe, making it possible to evaluate the adhesive joint and to detect delaminations in glass-fiber reinforced plastics.
The amplitude of the signal received is compared to a reference value, for example the amplitude of the initial signal. The frequencies required to detect flaws in honeycomb structures are relatively low (0.5 MHz).
In 1972, Schliekelmann reported the development ofa scanning device in the form of a rotating sensor to test metal-to-metal bondings. A hub filled with water is fitted with sensors, and several hubs are fixed with a rubber tire at each side ofthe sample. During scanning the tires rotate, while the sensors remain fixed and centered. Water jets are used as couplants by directing them towards the areas between the tires and the sample, where contact is needed. Among its disadvantages, this method does not permit the mapping ofdefects, and a couplant must be placed between the probe and sample to provide proper propagation of the applied ultrasound. For these reasons this procedure is generally excluded from use during manufacturing processes.
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