The corrosion behavior of AA7049 aluminum alloy in NaCl solution in the presence of environmentally-friendly corrosion inhibitors (Ce-chloride, Ce-formate, Ce-acetate, and Ce-propionate) was analyzed. The chemical composition of intermetallic particles was evaluated by a Scanning Electron Microscope, equipped for Energy Dispersive Spectroscopy measurements, while the presence of cerium and type of functional groups in inhibitors surface layers were analyzed by X-ray Photoelectron Spectroscopy and Fourier-Transform Infrared Spectroscopy, respectively. Inhibitor efficiencies were tested by applying electrochemical techniques such as Electrochemical Impedance Spectroscopy and Linear Sweep Voltammetry. Ce-propionate showed a greater inhibitory effect than all other tested corrosion inhibitors. The inhibitory effect decreases in the following order: Ce-propionate > Ce-acetate > Ce-formate > Ce-chloride. Propionate anions have a higher water contact angle and also a longer aliphatic side chain than acetate and formate anions. The mechanism of inhibitory action of Ce-propionate and other tested corrosion inhibitors has been proposed.

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The influence of microstructure and surface roughness of the X5CrNi18-10 austenitic stainless steel-welded joint on resistance to uniform, pitting, and intergranular corrosion, as well as on the stability of the passive film, was evaluated. The microstructure was revealed by optical microscopy and scanning electron microscopy, whereas surface topography and roughness levels were determined by atomic force microscopy. Corrosion characteristics were obtained by the electrochemical potentiokinetic reactivation method with double loop, electrochemical impedance spectroscopy method, as well as by potentiodynamic measurements. The degree of sensitization of heat-affected zone (HAZ) was significantly lower than the threshold value required for the occurrence of intergranular corrosion. However, HAZ showed a significantly greater tendency to pitting and uniform corrosion compared to weld metal and base metal. No effect of roughness levels (RMS from 3.6 to 54 nm) on the pitting potential value of the welded joint was observed (unlike in HAZ). The polished surface shows significantly higher corrosion resistance than the grinded surface. Generally, polishing improved corrosion resistance, especially in HAZ, which is very important because HAZ is a critical place for the occurrence of pitting and other types of corrosion.

This paper presents the effects of laser light irradiation on the surface of ceramics dating from archaeological site Stubline (Obrenovac, Belgrade), Serbia. Two different pulsed lasers: TEA CO2 (10.6 ?m wavelength, pulse duration tp = 100 ns) and Nd:YAG (wavelengths 1064 nm and 532 nm, tp = 150 ps) have been used for surfaces treatment. Laser irradiation fluence was in the range of 1-20 J/cm2. Ceramics surface modifications induced by pulsed laser treatment were examined by scanning electron microscope, SEM, and the composition with energy dispersive X-ray, EDX, analysis. The tests were performed in order to obtain as much as possible information about the appropriate choice of materials and techniques for the further conservation and restoration of these items. The second objective was to determine the surface modifications induced by pulsed laser treatment above damage threshold (a safe cleaning laser fluence), as an important parameter in the use of lasers for the cleaning of cultural ceramic items. [Projekat Ministarstva nauke Republike Srbije, br. TR 34028 i br. TR 34022]

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