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In parallel to the instrument development efforts, re- LIBS spectroscopy search was carried out in collaboration with NILES optimizing analytical methodologies for metal analysis. Also referred to as laser-induced plasma spectroscopy Tests were performed on reference samples prepared in LIPS , derives by time- and spectrally-resolving the collaboration with PROMET project end-users i.
To achieve this, a series of by focusing a nanosecond pulse from a laser on a solid systematic and detailed tests and evaluations have been surface laser ablation. The characteristic, sharp atomic made both on model and real samples. Corrosion inhibitors and protective coatings Another major innovation for this project was the search for new, safe, and effective corrosion inhibitors, coat- ings, and barrier films for the protection of cultural property made of metals.
Conference, Febru ary , Cairo, Eg ypt. Furthermore, some partners developed their. Centro Nacional de Investigaciones Metalurgicas, tools adapted and optimized for the needs of the conser- Consejo Superior Investigaciones de Cientificas, Spain. Laboratoire de Recherche des Monuments Historique, objects housed in the Mediterranean basin, such as lin- France. As reg ards coatings , silane coatings were deve loped for bronze.
Linear saturated sodium carboxylates; Azoles and natural extracts from Moroccan plants; Salts of Figure 1: Furthermore, innovative plasma processes for the depo- sition of barrier films and for suitable cleaning of the Figure 2: The SiO2-like coatings are transparent and characterised by high chemical and thermal stabil- The synergistic and combined real time application of ity, good dielectric properties, and low gas permeability.
The analysis of a mi- of objects in the Mediterranean region. Within PROMET, we were interested in testing and The first on site campaign at Ancient Messene in Pelo- developing temporary and permanent systems for cul- ponnese, Greece September , highlighted several tural heritage objects stored or exhibited in uncontrolled practical issues and gave the opportunity for further conditions. Corrosion inhibitors CIs usually respond to development and optimization of the system i.
The approach that we followed has been able LIBS instrument was tested on real gold, gilded outlined elsewhere,2,13 and is summarised in Figure 3 as and bronze artifacts from the Archaeological Museum well as some important points are highlighted below. Methodology followed by PROMET partners to simulate in a better way natural corrosion forms simi- for testing traditional and innovative protection systems. The corrosion progress was followed during the exposure period, and after 3, 6 and 12 months binocular observations, colour change measurements, To avoid initial testing of the different protection sys- SEM-EDS investigations were carried out on the series tems on real objects, it was necessary to manufacture of removed coupons.
Furthermore, duplicate metal coupons could be tested to ensure the reproducibility of the results. The consortium devised several protocols for testing, examining, and analysing the protection systems se- lected on pre-corroded metal coupons. Short-term test- ing was first considered on artificially aged coupons for a preliminary selection of protection systems. Long- term testing was carried out afterwards on naturally aged coupons to assess the effectiveness of the most promising protection systems in real conditions of expo- sure.
The products that behaved the best were finally tested on real objects. The artificial ageing of the metal coupons aimed at reproducing the corrosion layers found on historic ob- jects for steel, bronze and silver based alloys and ar- chaeological objects for silver objects. For silver based coupons the TEI Athens.
Now it remains were considered for historic and archaeological bronze to take the prototypes and protection systems developed objects. Conclusions logical Educational Institute of Athens T. Spyridonos, Aigaleo - Greece , Email: Still many challenges remain in order to ensure that the bessie teiath.
Haddad, Devel- and reliable equipment remain important.
Specifically, oping Innovative Portable Diagnostic Techniques and the tailored optimisation of the hardware components Approaches for the Analysis of Metal Artefacts from for reducing the sampled area in order to achieve a mi- Museum Collections, In: Chapuis, cro-beam spot of analysis that enables the investigation Eds. Protecting, Preserving, and Interpret- morphology and chemical composition. For the protection systems to improve the synthesis 3. Fotakis, Laser Diagnostics conditions of these new safe protection systems and to of Painted Artworks: Laser Induced Breakdown Spec- identify the technological aspects that require adjust- troscopy of Pigments, Appl Spectrosc, , 51, ment for passage to an industrial pilot scale: Anglos, Laser-Induced Breakdown Spectroscopy ration of the corrosion inhibitor solutions in large in Art and Archaeology, Appl Spectrosc, , 55, quantities to evaluate the manufacturing process, AA.
Tognoni, large scale on real objects belonging to museum Self-calibrated quantitative elemental analysis by laser- collections.
Kilikoglou, products developed for the conservation market V. Spizzichino, Laser- induced breakdown spectroscopy for semi-quantitative and quantitative analyses of artworks—application on multi-layered ceramics and copper based alloys, Spec- trochim Acta Part B, , 57, Stege, Evaluation of the analytical potential of laser-induced breakdown spectrometry LIBS for the analysis of historical glasses, Ar- chaeometry, , 45, Vallebona, A, Zanini, Archaeometric analysis of ancient copper artefacts by laser-induced breakdown spectroscopy technique, Microchim Acta, , , Vella, Methodology for the in-situ analyses of historic steel armours with portable milli and micro-XRF spectrometers, In: Samara, Copper alloys and silver objects protection by coatings with nano-alumina pigments.
Remember me on this computer. Enter the email address you signed up with and we'll email you a reset link. Click here to sign up. The long-term testing consisted in using the most effec tive. The coupon exposure rack design. Mechanical cleaning of the coupons at the end of the exposure. Each partner chose three best rated protection systems from. These protection systems were t ested. All protection systems were app lied either b y profes-. T he application protocols were.
At that stage the differe nt. Table 1 gives the choice of protection systems for the 4 partners. Each protection system was tested on. A thorough m onitoring of the cou pons wa s required to deter -. HM for inst ance developed. Also, RH and T were recorded all. Coupons were once again removed at regular periods 3, 6 and These experiments are currently in.
Two vertical racks with bronze and steel coupons expo-. Oblique rack with bronze coupons in position in the. Due to the impossibility to. Sodium carboxylate new formula in th e. A and FPT S were considered for histor ic and archaeological. The other part was pro tected with. Such a strateg y of testing protection systems for c ultural prop-. Mechanical cleaning of all steel coupons aged naturally by a professional conservator a and application of protection.
Reference coupons are without protection systems. Diffusion t ubes are put aside the oblique rack for. Our research considered the option t o change th e formu-. But other innovative protection systems have given.
Safe corrosion inhibito rs like. Such testing could be carried out in. Further work is required as well on the long-. Also, new and safe protection systems are at our disposal. The authors are gr ateful to the 6 th F ramework Programme, pr i-. Further acknow ledgements and gratitude go to the individual.
Picreator Enterprises L td. Innovative conservation approaches for monitoring and protecting ancient. H allam and Ashton, Canber ra, Mich alakakos and A. A survey of the t ypes of corrosion inhibitors and. Conference, Febru ary , Cairo, Eg ypt. A Standardised Rem ote Monitoring Ph otographic.
Character isation of corrosion product layers on atmospheri-. Februar y , Cairo, Egy p t. Hajjaj i and A. Development of n ew organic inhibito r. New corrosion inhibitor containing Opuntia Fic us.
Protocols compiled by the author f rom personal exp erience and dat a from L. Brostoff, , Coating strategies. Degrigny , Western A ustralian M useum,. Measur ing the thickness of protective coatings on. Cor rosion inhibitors for metallic ar tefacts: Polikreti an d A. T esting new coating syst ems for the. A preliminary st udy of the morphology of corrosion developing onto historic steel. The Hague, Netherlands, 31 The main difference with previous works was that coatings were applied on pre-corroded steel coupons simulating historical objects.
EIS results showed a good agreement with other accelerated exposure tests, but had the advantages of a shorter test time and provides information about the mechanisms or protection and coating failure [9,79, 80]. Protection coatings for silver and silver alloys have also been tested using EIS. While corrosion layers and patinas on copper and iron based metallic artefacts are usually preserved, and therefore the protection layers are to be applied over them, in the case of silver based objects it is usually desirable the elimination of any corrosion layer or tarnishing, and the coatings are applied on the clean surfaces.
Use of EIS for the evaluation of the protective properties of coatings for metallic cultural heritage: The best way to reduce the degradation of metallic cultural heritage is through preventive conservation measures but, in many cases, it is not possible to obtain adequate environmental conditions, and it is necessary to apply coatings to the artefacts in order to protect them against corrosion.
There is a continuous search in the metal conservation community for new and improved coatings that provide a better protection to the objects whilst respecting the special requirements of the conservation—restoration ethics. Whilst electrochemical techniques have a long tradition in conservation—restoration treatments for metallic cultural heritage, the evaluation of protective coatings using electrochemical impedance spectroscopy EIS has only been used very recently. EIS is a very well-established method to investigate metal coatings for general purposes and has many advantages that make it especially suitable for testing coatings for metallic works of art.