Influence of Manufacturing Processes in Deterioration of Ag-Cu Artefact Alloy
Issue:
Volume 8, Issue 1, June 2020
Pages:
1-5
Received:
10 December 2019
Accepted:
20 December 2019
Published:
4 January 2020
Abstract: Ancient silver with about 2% copper object is studied to determine manufacturing defects based on chemical and microscopic investigations. In this paper Bullion (silver-copper alloy) ink box inlays with enamel from the Museum of the faculty of applied arts in Cairo, Egypt has been investigated to identify manufacturing process and its effect on the ink deterioration. Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectrometry (SEM-EDS) method has been used on samples to reveal chemical composition of the alloys and the effect of various fabrication and thermal treatment. The results indicated that all samples were made of silver-copper alloys, other elemental corrosion layers have detected in contents such as C, O, S, Cl, Si, Na, Ca, Al. Fracture surfaces provide with important information helping to recognize failure causes, so the fracture surface investigation and etching by means of alcoholic ferric chloride was carried out for microstructural analysis. Scanning Electron Microscopy SEM-micrograph of etching sample showed pores and cracking propagation. Crack initiation usually appears at the object surface, and is generally produced by stress concentrators, producing rise to local plastic deformation or cracking and detachment of brittle precipitates. Local stress–strain concentration related to a variety of microstructural inhomogeneities. The X-ray diffraction analysis (XRD) confirmed the EDX analysis that the corrosion compounds consist of Montmorillonite NaO3(Al, Mg)2Si4O10(OH)2XH2O, Atacamite Cu2Cl(OH)3, Malachite Cu2CO3(OH)2, Paratacamite Cu2Cl(OH)3, Cuprite Cu2O, Acanthite Ag2S, Tenorite CuO, Calcite CaCO3, Chlorargyrite AgCl, Copper Cu. Silver–copper alloys failed through corrosion process that produce brownish-black tarnish. This tarnish alters the aesthetic of the object. The corrosion layers of the object referred to long-term contamination and oxidation, which led to increase intergranular cracking, regions of ductile fracture, and brittle intergranular fracture.
Abstract: Ancient silver with about 2% copper object is studied to determine manufacturing defects based on chemical and microscopic investigations. In this paper Bullion (silver-copper alloy) ink box inlays with enamel from the Museum of the faculty of applied arts in Cairo, Egypt has been investigated to identify manufacturing process and its effect on the...
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Treatment of Paper Oxidation and Acidification by Linseed Gel with MgHCO3 and Zinc Oxide (NP)
Wafika Noshyutta,
Rushdya Rabee Ali Hassan,
Mohamed Awd
Issue:
Volume 8, Issue 1, June 2020
Pages:
6-14
Received:
23 April 2020
Accepted:
19 May 2020
Published:
8 June 2020
Abstract: Collection paper in museums and libraries and stores suffer from acid hydrolysis and oxidations, many factors catalysis the deterioration by acid hydrolysis and oxidations, such as humidity and temperature and light and fungi, paper contains iron ink and colors based on ions heavy metals such as copper and zinc, air pollution, visible and industry light, Residues of manufacturing processes such as bleaching material, additives such as sizing materials, The study proposes a new antioxidants agent by using Line seed gel with magnesium bicarbonate loaded with Zinc oxide (NP), the positive impact of this treatment was evaluated on thermally accelerated ageing on cotton, linen and wooden samples, the samples was verified by FTIR, tensile strength and elongation measurement, Measurement of color change, PH measurement, aromatic hydroxylation assay, (SEM) scanning Electron microscope, Linseed gel with MgHCO3 and Zinc oxide (NP) results to stabilize inks and stop oxidation that occurred and treatment of free radicals, the inks were most stable, The mechanical properties of the samples have been greatly improved, Linseed gel with magnesium bicarbonate loaded with Zinc oxide (NP) consolidation and treatment the samples, the zinc oxide (NP) nano oxide was observed between the fibers which works to protect the cellulose fibers From degradation.
Abstract: Collection paper in museums and libraries and stores suffer from acid hydrolysis and oxidations, many factors catalysis the deterioration by acid hydrolysis and oxidations, such as humidity and temperature and light and fungi, paper contains iron ink and colors based on ions heavy metals such as copper and zinc, air pollution, visible and industry ...
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