First step in the PROCRAFT Project on WWII Aircraft Heritage: Investigation and Conservation of the Aluminium Alloys

International audienceThe conservation of excavated wrecks or abandoned aircraft is of cultural and historical interest. A first step in understanding the challenges posed by this type of cultural heritage and in finding solutions for its conservation is to document the constituent materials and their subsequent alterations. In the project PROCRAFT, aircraft wrecks from six nations involved in WWII were collected and then studied. Analysis of the elemental composition together with archival research allowed identification of the wrought aluminium alloys used in the non-structural and structural parts of the aircraft. Three manufacturing processes were recognised: rolling, extrusion and forging. The corrosion protection treatments applied during manufacturing of the aircraft parts were also examined, which revealed cladding with a thin aluminium foil, anodisation or the application of primer/paint. Based on typical examples of the alterations that occurred in the metal components, we demonstrate the importance of this original protection against the aggressiveness of the environment