Storing and exhibiting cultural heritages are the basic social functions of museum. Since it is impossible to store or display objects without using containers, cases, or holders, the equipment ...quality is of great importance. Evaluating the suitability of the equipment should not only learn the mechanical behavior but also focus on the materials because some of them (such as woods) may do harm to the objects due to contaminants released. A convenient test by the deposited metal film method has been proposed previously in order to evaluate more potential museum materials in limited time. The conformance between this method and the Oddy test, the classic method for evaluating and selecting museum materials, is mainly studied in this work. The two testing systems were compared from several aspects such as sample appearance, corrosion product, surface morphology, and metallic content by naked eye and modern characterization measures like X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. The corrosion mechanisms were deduced according to the corrosion products, including Cu → Cu
2
O → CuO and Cu → Cu
2
O → Cu(OH)
2
·H
2
O → Cu(HCOO)(OH). The suitability of potential materials for the conservation of metal objects was defined according to the metallic contents of coupons (calculated by atomic ratio) which were classified by the Oddy test. The critical values distinguishing permanently usable from temporarily usable are approximately determined as 70% for copper and 75% for silver, and those distinguishing temporarily usable from unusable are approximately determined as 55% for copper and 60% for silver. The corresponding metal films were classified based on the metallic content standard derived, and then typical appearances of the films assigned to different suitability levels were suggested. Special phenomena, such as the failure in detecting some corrosion products, is attributed to low yield and uneven distribution of ultrafine corrosion products on the films, the covering effect caused by other corrosion products on the copper coupons, and the weakening effect resulted from intensive metal peaks, while some unexpected corrosion conditions on the coupons and the films, are related to the characteristics of general corrosion and pitting corrosion. The results indicate the potential application of the deposited metal film method, giving an optional choice to evaluate and select museum materials with less time. The evaluation methods were preliminarily established from three aspects, such as artificial judgment, metallic content analysis, and corrosion product identification. The artificial judgment is generally applicable, and the other two are useful for verifying the result if possible. More actual cases and further calibration work are essential for further development of the deposited metal film method.
Colour changes of cultural heritage objects can be related with degradation of materials, thus a proper colour monitoring system can be used to detect conservation problems. With this purpose, a ...monitoring methodology for cultural heritage preventive conservation based on tailored colour reference charts and image analysis is proposed.
Reference colour charts have been designed and tested for use in museums. Charts containing 64 colour patches have been printed using high-stability inks on 4 different substrates: Acid-free paper SkyLight, Acid-free paper covered with a propylene film, FOREX® and GlassPack. The stability has been studied by accelerated ageing in an UV chamber, and the harmlessness of the materials by Oddy Test. The final selection of material, laminated paper, is a balance between the colour change upon ageing and the performance in the Oddy Test. Using this material and the proposed design, colour change of copper and silver coupons has been assessed using images that are adjusted and calibrated by an adaptive calibration framework employing a given set of reference colours which homogenises the visual information in the supplied images. Thus, regardless of the camera of origin, any processed picture will deliver reliable information of the state of the colour in the metal surfaces at the moment it was taken.
Results demonstrate the adequacy of the approach and the design for colour calibration, so these charts can be used to monitor colour change of sensitive materials –metal coupons– using photographs. As colour change of reference metals is a consequence of corrosion by environmental factors this may be used as a measure of air quality in museum environments. This methodology can be used to design a low-cost preventive conservation tool, where colour change of metal coupons –or other reference materials– can be followed through image analysis of pictures taken periodically by conservators or visitors, introducing citizen science in the conservation strategy.
Conservators’ decisions regarding the suitability of museum construction materials for use in proximity to artworks still rely heavily on accelerated corrosion tests like the Oddy test despite ...widespread criticisms. These issues include inconveniently long wait times, sensitivity to only those pollutants capable of tarnishing metals, a general sense of unreliability, exaggerated environmental conditions, and subjectivity in assessing the test’s results. Increasingly, alternative strategies that use instrumental approaches involving volatiles sampling coupled to gas chromatography with mass spectrometry (GC–MS) are being explored as faster, more comprehensive, potentially quantitative, and possible more ‘objective’ means of assessing the dangers of off-gassing from museum construction materials. While many of these characteristics are now well documented, the objectivity of the instrumental result is arguable. While the detection of volatiles and semi-volatiles by GC–MS can confidently yield a list of potential pollutants, “chemical intuition” must be used to predict whether many of the emitted compounds can in fact adversely affect artwork. In this study, evolved gas analysis (EGA) coupled to GC–MS is used to predict the suitability of a small sample set of plastics for use in a museum. The potential impact of volatiles observed in the EGA chromatogram was assessed using chemical reactivity principles and the sparse literature data on the material damages caused by a small group of known pollutants. These same plastics were then tested using the British Museum’s 3-in-1 Oddy test. The prediction based on an educated chemical assessment of the compounds identified through instrumental analysis shows good correlation with pooled results from the Oddy test. In one of the two instances of disagreement, the EGA analysis was actually overly conservative and leaned toward prohibiting or restricting a material that passed the Oddy test. In the other, a material that failed the Oddy test but was passed by instrumental analysis was later shown to contain VOCs that could be considered corrosive. This trial suggests that with practice and experience instrumental approaches may be useful to supplement and perhaps one day supplant traditional accelerated corrosion testing of museum construction materials.
Journal of the Institute of Conservation Stopping corrosion around the world: an investigation into protective surface coatings on arms and armour material testing; Oddy test; protective coating; ...surface coating; oil; wax
An identification and amount of corrosion on the pipeline which is located at bottom of the sea can be achieved by utilizing information obtained from colored corroded pipes and by estimating through ...the oddy test. This study proposes an algorithm for enhancing the quality of deteriorated underwater images. The algorithm aims to reduce blurring effects and improve the quality of the images, which subsequently aids in the corrosion estimation and detection process. In order to estimate the corrosion age, the oddy test is utilized, which is typically used to determine the quality of materials that are suitable for storing, transporting, or displaying museum objects. A convolution neural network is employed to categories the corrosion rate detected at corroded pipes. An images used for object detection and training the CNN are obtained from the various source which can be accessed publicly. In the defined algorithm, a result of 98% accuracy is achieved, and the algorithm is capable of estimating the approximate age of the corroded pipeline.
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