Copper alloy samples are subjected to climate chamber test to simulate corrosion compounds of copper artifacts in atmospheric environment. Relative humidity and air pollution considered as an essential source of deterioration and corrosion of archaeological objects. Corroded copper coupons were investigated by X-ray diffraction analysis (XRD) and scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX) to identify elemental composition of coupon samples and the corrosion products. Mechanical cleaning was used in order to clean the copper coupon surface and carried out nanocomposite coating on treated copper surface. To evaluate performance of titanium dioxide TiO 2 / Paraloid B.72 nanocomposite, the nanocomposite coating applied as a thin film at different times (10, 15, 30 minutes). The electrochemical impedance spectroscopy (EIS) of nanocomposite coating layers on treated copper coupons showed different results; that the best layer was obtained from the coupon which immersed in nanocomposite coating for 15min. To prove successes of TiO 2 / Paraloid B.72 nanocomposite as a good protection coating applied on treated copper objects. Nanocomposite coating of TiO 2 / Paraloid B.72 were examined under X-ray diffraction analysis (XRD), Raman Spectroscopy, Atomic Force Microscopy (AFM), and Contact angle, which revealed control the wettability and TiO 2 / Paraloid B.72 nanocomposite is completely covers and protects the copper substrate without any degradation.

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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 NaO 3 (Al, Mg) 2 Si 4 O 10 (OH) 2 XH 2 O, Atacamite Cu 2 Cl(OH) 3 , Malachite Cu 2 CO 3 (OH) 2 , Paratacamite Cu 2 Cl(OH) 3 , Cuprite Cu 2 O, Acanthite Ag 2 S, Tenorite CuO, Calcite CaCO 3 , 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.