Analysis of Corrosion Products on Underwater Iron Cannon Artifacts from Hainan Province Museum

There are 7 iron cannons conserved in Hainan Province Museum, these iron cannons sunk in the sea for a long time. Different metal working technologies in various periods results in different levels of corrosion of iron cannons. To conserve and restore the underwater iron cannons is an important issue The composition and structure of the corrosion products from these iron cannons were analyzed using X-ray fluorescence (XRF) and X-ray diffraction (XRD). The results show that the rust includes Fe3O4,α-FeOOH,β-FeOOH or Fe8(O,OH)16Cl1.3 and γ-FeOOH. The harmful rust γ-FeOOH must be removed. All the information will be useful to guide the desalination after the surface rust is moved.