Abstract: Studies are made on the source mechanism and characteristics of acoustic emission (AE) signals produced by corrosion, especially pitting corrosion. Relationship between AE amplitude and corrosion depth and frequency is deduced, and the significance of the relation in estimating corrosion damage is emphasized. Theoretical basis for using modal AE to identifying corrosion-related AE and background noise is introduced, and methods for using modal AE to evaluate calendar damage of aircraft main structures are outlined. Relationship between corrosion damage and AE parameters is obtained through accelerating corrosion test, showing the great potential of using AE to detect early corrosion, to monitor corrosion development, and to evaluate corrosion damage.

Key words: Aircraft, Corrosion damage, Acoustic emission(AE), Corrosion, Modal acoustic emission(MAE)