CORSENSAL

Due to their low density and good mechanical properties, aluminium alloys are the materials of choice in the field of aeronautics, especially for aircraft production. Among the many grades available, AA2024-T3 alloy is the most widely used for structural parts. The presence of significant amounts of copper and magnesium in this alloy improves mechanical properties but leads to the formation of intermetallic particles with heterogeneities in terms of electrochemical reactivity. This leads to an increase in the sensitivity of this material to corrosion as well as the appearance of localized corrosion, mainly intergranular. This problem is particularly accelerated in the presence of chloride in the marine environment or when de-icing salts are used. In this context, the monitoring of the sensitivity of the AA2024-T3 alloy to atmospheric corrosion as well as the knowledge of the electrochemical processes responsible for it are essential points to i) optimize maintenance operations and ii) guarantee the operational availability of aircraft. The CORSENSAL project focuses on the monitoring of confined areas inside aircraft, which are often inaccessible and have condensation problems. In this case, sensors that are sensitive to corrosion and mass loss can be used. Despite the interest of the latter, their large-scale deployment for the implementation of SHM (Structural Health Monitoring) methods in the field of aeronautics is difficult to implement. The main problems are (i) their compatibility with operating conditions (temperature, battery life, presence of cables), (ii) their cost, and (iii) the difficulty of interpreting the data from the sensors when localized corrosion exists. The objective of this project is to propose an innovative solution to remove these technological barriers. It is based on RFID (RadioFrequency IDentification) technology. In this case, the sensors are interrogated remotely by a radio frequency reader. Since they have neither batteries nor electronic components, they can be used in harsh environments over during very long periods of time. In addition, their very low cost allows for large-scale deployment. The objective of this project is to apply this innovative technology to the monitoring of corrosion of the AA2024-T3 alloy inside aircraft. To achieve this goal, the CORSENSAL project aims to develop RFID sensors that are sensitive to localised corrosion, which is a challenge compared to existing solutions. They are made of metallic parts produced from aluminum alloy sheets and exposed to corrosive environment. The low thickness of the sheets ensures the sensitivity to corrosion. In this project, a correlation will be established between the response provided by the sensor using alloy foils and the corrosion progress of the massive alloy AA2024-T3. In this context, a statistical analysis of the corrosion progression on different aluminum alloys with different microstructures will be conducted. Only this method will provide relevant information on the corrosion progress of the solid alloy and of the aircraft.