Galvanic Corrosion in Aerospace Structures

Abstract

Aircraft and helicopter structures commonly incorporate a combination of high-strength, low-density materials, such as carbon fiber-reinforced polymer (CFRP) and aluminum alloys, which are joined mechanically (e.g., fasteners, rivets) or physicochemically (e.g., adhesives, welding). While these structures are mechanically optimized, their durability can be compromised by galvanic corrosion when materials with different open circuit potentials are in electrical contact. A typical example of such a joint is the mechanically fastened CFRP-AA2024 connection. This thesis investigates the less understood process of galvanic corrosion using an in-situ reflected microscopy technique combined with electrochemical potential noise, complemented by post-mortem scanning electron microscopy (SEM) and Raman analysis. Additionally, the study explores the use of environmentally sustainable materials to improve the system's eco-friendliness without sacrificing protective performance.