The Defect Identification and Localization using Ultrasonic Guided Waves in Aluminum Alloy

Abstract

The assessment of damages in the aircraft components is a key aspect to avoid structural failure. In general, damages may occur due to flight load, accidents during the maintenance and environmental conditions. Primary airframes such as aircraft wings and fuselages are covered with thin aluminum alloys. The damages in the aircraft wing skins are posing a serious threat. The traditional non-destructive testing (NDT) often requires dismantling the component for inspection, consuming more time. Guided wave structural health monitoring (GWSHM) is an alternative to inspect the large structures, it is a time saving and cost-effective. However, the defect identification and localization using multi-mode and highly dispersive guided waves requires significant knowledge. In this research, multiple defects are examined by performing numerical simulation. The defect can be identified and located by measuring the Time of Flight (ToF) and delay time of a signal. The Hilbert Transform (HT) and Zero-crossing techniques are used to measure the ToF of the signal to enable defect presence and the delay time between two signals are analyzed to enable defect location.