• Journal of Conservation Science
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• v.25 no.1
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• pp.49-60
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• 2009

Outdoor iron artefacts are easily corroded by salts, especially $Cl^-$ion, from environmental pollutants and acid rain because of their location, so that they need conservational treatments such as stabilization. However the conservation of outdoor iron artefacts are limited to be consolidated for the present and there are a few the studies for the desalinization. The general desalinization method is that objects are immersed in reagent such as alkaline corrosion inhibiting solutions targeting on buried iron artefacts, thus they are not available for outdoor iron artefacts. In this study, concerning those difficulties, the different desalting method is experimented that materials soaked in alkaline solutions attach to objects and they are packed by waterproof to avoid evaporation. This paper experiment burial iron artefacts at first in order to fine out an adaptable method for outdoor iron artefacts. The soaking materials are Korean traditional paper, gauze, cotton wipers, spill pads and the desalting regent is NaOH 0.1M. Additionally the exiting desalinization method which is to immerse objects in solution is performed to compare. The analyses are microscopes, SEM-EDS, X-ray diffraction, pH meter and Ion chromatography. The result is that spill pads show the best desalting effect out of other materials similar to immersing desalting method.

• Corrosion Science and Technology
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• v.18 no.4
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• pp.121-128
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• 2019

Electrochemical Impedance Spectroscopy (EIS) was used to predict corrosion behaviour of metallic Cultural Heritage assets in two monitoring campaigns: 1) an iron bar chain exposed indoor from over 500 years in the Notre Dame Cathedral in Amiens (France); and 2) a large weathering steel sculpture exposed outdoor from tens of years in Ferrara (Italy). The EIS portable instrument employed was battery operated. In situ EIS measurements on the iron chain could be used to investigate the phenomena involved in the electrochemical interfaces among various corrosion products and assess and predict their corrosion behaviour in different areas of the Cathedral. Meanwhile, the sculpture of weathering steel, like most outdoor artefacts, showed rust layers of different chemical composition and colour depending on the orientation of metal plates. The EIS monitoring campaign was carried out on different areas of the artefact surface, allowing assessment of their protective effectiveness. Results of EIS measurements evidenced how employing a simple test that could be performed in situ without damaging the artefacts surface is possible to quickly gain knowledge of the conservation state of an artefact and highlight potential danger conditions.

• Journal of Conservation Science
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• v.25 no.4
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• pp.399-409
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• 2009

Outdoor iron artefacts are easily corroded by affection of environmental pollutants directly. Especially they need to be removed $Cl^-$ ions, but outdoor iron artefacts are excluded for desalination owing to their special features. Therefore this study contains the conservation processes of an iron stele of the Joseon Dynasty as the sample as well as desalination experiments that were carried out the desalting method using spill pads and the immersion desalting method together in order to compare. Desalting methods were compared by analyses such as an optical and metallurgical microscope, SEM-EDS, pH meter, Ion Chromatography and X-ray diffraction. As a result of the analysis, the optical and metallurgical microscopy show that the corrosion products are constituted by the layers and the metallurgical microstructure is a white cast iron. The SEM-EDS results of corrosion products detected mainly Fe, O, and especially Cl upto 2.48wt%. The results of pH and anion analysis for the washing solution, the desalting method using spill pads shows the similar effect to the immersion desalting method. As a result of XRD analysis before and after desalting corrosion products, goethite, magnetite, lepidocrocite and akaganeite are detected before desalting, but akaganeite is not detected after desalting at the desalting methode using spill pads, which indicates to have an effect on desalination. Therefore the results show that the desalting method using spill pads has an effect on desalination similar to the immersing desalting method.