Early detection and progress monitoring and prediction of corrosion in aeronautic Al alloys through calibrated Ultrasonic CorROSion Sensors application

The U-CROSS project addressed the early detection of corrosion in aluminium aircraft components, a crucial need given the extensive use of aluminium alloys in aviation for their high strength-to-weight ratio. Traditional non-destructive testing (NDT) methods are limited, only detecting corrosion after significant damage has occurred. This limitation often results in corrective actions being taken too late, leading to critical damage like cracks or loss of thickness.

To overcome these challenges, U-CROSS developed an advanced ultrasonic sensor combining active and passive elements. This sensor was designed to detect the initiation of localized corrosion and monitor its propagation over time, providing real-time data on the early stages of corrosion. The project aimed to implement this sensor in the aircraft industry to prevent severe damage and enhance the longevity and safety of aircraft components.

The project followed a systematic approach to validate the ultrasonic corrosion sensors (UCS). It involved creating "model witness blocks" to calibrate the sensors, taking into account the unique characteristics of various corrosion mechanisms. The selected UCSs were used for cumulative and real-time monitoring, depending on the specific type of corrosion. The sensors were tested in both indoor and outdoor environments to ensure their reliability and effectiveness.

Additionally, U-CROSS developed a software tool to assist end-users in designing and using the sensors. This tool could predict the number of cycles before critical damage occurred, providing valuable insights for maintenance and prevention strategies. The consortium included three research organizations, a NADCAP accredited SME for testing painted parts, and a leading European manufacturer of UCSs and ultrasonic inspection systems. Their combined expertise aimed to ensure the future commercialization of the project's outcomes.

By focusing on early detection and continuous monitoring, U-CROSS contributed significantly to preventing critical damage in aircraft components. The project's innovative approach promised to enhance the safety and reliability of aircraft, offering a competitive edge to the European aerospace industry.