A novel ultrasonic probe for the evaluation of corrosion in aluminum aircraft panels

A novel ultrasonic probe has been developed for testing in aircraft panels. The probe has four transducers mounted on a single angle block, two of which are in-line, facing each other, while the other two are at orthogonal positions. A pulse of shear wave transmitted by one of the in-line transducers undergoes zig-zag reflections in the aluminum aircraft skin and is received by the in-line receiving transducer, directly facing the transmitter. Other transducers, collect sound waves scattered from underlying cracks, corrosion, inclusions or cavities. The transmitted and scattered data from the four transducers are made use of in characterizing the corrosion in aluminum panels. The current work discusses the measurement technique adopted and the method of analyses used in the NDE of corrosion