Electrochemical noise evaluation and data statistical analysis of stressed aluminium alloy in NaCl solution

Cast iron has stood for centuries of invention. It is a very versatile and durable material. Coating systems are a low-maintenance protection method. The purpose of this research is to increase the Paraloid coating’s resistance when applied to iron in high humidity atmospheres, with the addition of caffeine (1,3,7-dimethylxanthine) and nicotine (S)-3-(1-methylpyrrolidin-2-yl) pyridine as corrosion inhibitors; the resistance of protection versus exposure time will be evaluated by using electrochemical noise. A statistical analysis of the electrochemical noise signals was carried out. Recurrence plots were used as a powerful tool in the analysis to complement the data obtained and they predicted the evaluation of coatings behaviors performance versus time. The outcomes show that the addition of inhibitors increases and improves the performance as a temporary protection of Paraloid and that protection in high relative humidity was improved. Recurrence plots and parameter quantification show the variances in the surface corrosion dynamics.

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Crevice Corrosion Behaviors of X52 Carbon Steel in Chloride Containing Solutions

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.1432 ◽

2013 ◽

Vol 652-654 ◽

pp. 1432-1435

Author(s):

Qian Hu ◽

Jing Liu ◽

Jie Zhang ◽

Feng Huang ◽

Xing Peng Guo

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Carbon Steel ◽

Impedance Spectroscopy ◽

Crevice Corrosion ◽

Electrochemical Noise ◽

Electrochemical Impedance ◽

Corrosion Process ◽

Nacl Solution ◽

Concentration Difference ◽

Corrosion Behaviors

The crevice corrosion behaviors of X52 carbon steel in two typical Cl--containing solutions were investigated by electrochemical noise and electrochemical impedance spectroscopy. Results show that oxygen concentration difference leads to the coupled current in NaCl + NaHCO3 solution while HAc concentration difference causes the coupled current in NaCl solution saturated with CO2 in the presence of HAc. There exists an apparent incubation stage during the crevice corrosion process of X52 carbon steel in the former. However, no obvious incubation period of crevice corrosion can be observed in the latter. Micrography shows that the crevice corrosion occurs indeed and the corrosion inside the crevice is not uniform.

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Orientation distribution analysis in deformed grains

Journal of Applied Crystallography ◽

10.1107/s0021889801003077 ◽

2001 ◽

Vol 34 (3) ◽

pp. 280-288 ◽

Cited By ~ 39

Author(s):

Jean Christophe Glez ◽

Julian Driver

Keyword(s):

Statistical Analysis ◽

Aluminium Alloy ◽

Orientation Distribution ◽

Distribution Functions ◽

Distribution Analysis ◽

Practical Application ◽

Orientation Data ◽

Alloy Crystal ◽

Orientation Distribution Functions ◽

Individual Grains

Some improvements are proposed for the statistical analysis of orientation data within individual grains, in particular by allowing for crystallographic symmetries. A method based on quaternions is then presented to characterize orientation spreads including anisotropic effects. Based on this approach, some analyses of disorientation distributions (orientation distribution functions, disorientation noise and the description of sub-boundary disorientation) are reconsidered. The analysis is illustrated by a practical application to the microtextures of a hot deformed aluminium alloy crystal.

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Study On the Corrosion Resistance Properties of the Ceramic Coating Obtained Through Microarc Oxidation on the Aluminium Alloy Surface

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.1733 ◽

2007 ◽

Vol 353-358 ◽

pp. 1733-1736 ◽

Cited By ~ 1

Author(s):

Fei Chen ◽

Hai Zhou ◽

Chen Chen ◽

Fan Xiu Lu ◽

Fan Xiu Lu

Keyword(s):

Corrosion Resistance ◽

Aluminium Alloy ◽

Ceramic Coating ◽

Microarc Oxidation ◽

Electrochemical Corrosion ◽

Nacl Solution ◽

X Ray Diffraction ◽

Micro Arc Oxidation ◽

Coating Formation ◽

Α Al2o3

Oxidation ceramic coating was directly synthesized on LY12 aluminium alloy by micro-arc oxidation (MAO) process in Na2SiO3 electrolyte solution with the Na2WO4-KOH-Na2EDTA addition. The corrosion resistance of the coating was tested using CS300P electrochemical corrosion workshop in 3.5% NaCl solution. Using the scanning electron microscopy (SEM) and X-ray diffraction (XRD), the cross-section microstructure, the surface morphology and the phase structure of the micro-arc oxidation ceramic coating were analyzed. The results showed that the corrosion resistance of the micro-arc oxidation ceramic coating in 3.5% NaCl solution was enhanced remarkably, the corrosion velocity was obviously slowed down. The thickness of micro-arc oxidation ceramic coating was about 11μm. The final phases in the coating were found to be α-Al2O3 and γ-Al2O3. The mechanism of the oxidation ceramic coating formation was investigated too.

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