A method for detecting and preventing corrosion in aeronautics

CIDETEC Surface Engineering’s U-CROSS project has developed a preventive corrosion detection system based on the Acoustic Emission technique

Corrosion control is one of the biggest challenges for the durability (useful life) of structures and functional materials. Corrosion is difficult to detect in its early stages and, in an advanced state, can lead to costly repairs for companies. Corrosion damage can be critical to the functionality of a structure if undetected and, in a demanding industry such as aeronautics, this could have catastrophic consequences.

After four years of research, the recently completed European U-CROSS project, under the coordination of CIDETEC Surface Engineering and directed by Dassault Aviation, has led to promising results in the development of a monitoring system for diagnosing and predicting (prognosis) the corrosion condition of aircraft. Specifically, the project focused on monitoring based on the Acoustic Emission (AE) technique to detect corrosion, in its incipient state, affecting aeronautical structures, enabling preventive anticipation of critical damage that could threaten their structural safety.

The U-CROSS project has obtained these results thanks to experimental work in the laboratory, complemented by real exposure in the outdoor environment. Advanced analysis to investigate recorded AE data has been essential to implement a monitoring solution capable of identifying the early stages of localized corrosion (pitting and intergranular) suffered by aluminium alloys or corrosion under paint (filiform corrosion). On the other hand, based on experimental work, models have been defined to predict the coating degradation and lifetime of aluminium alloy affected by corrosion. The results have been validated through a monitoring system based on EA, installed on a real panel extracted from the fuselage of a Falcon 7X and exposed to real environmental conditions, thus enabling the localization of the corrosion.

As part of the Clean Sky 2 programme, U-CROSS has been funded with a budget of around €1.5 million and the participation of the Communaute d’ Universités et Etablissements Université Bourgogne – Franche – Comte (UBFC), Titania Ensayos Proyectos Industriales S.L., Mistras Group SAS and the Institut National des Sciences Appliquées de Lyon. The project will contribute to improving aircraft safety through early detection of corrosion, i.e. a preventive approach that will lead to more cost-effective solutions for the industry. In addition to improving the competitiveness of the European aviation industry, this solution is aligned with the objectives of reducing the environmental impact of aviation and promoting its sustainability.