Determination of corrosion types from electrochemical noise by phase space reconstruction theory

Blocking Hydrogen Diffusion in Palladium Cathode i—Analyzed by Electrochemistry; ii—Analyzed by Chaos

Electrochemical chaos is caused when, during diffusion, hydrogen and, at worst, tritium is trapped in palladium after the formation of adsorbates. The mechanism leads to cracking corrosion, as seen by scanning electron microscopy. The instabilities were apprehended from voltammetry and electrochemical impedance spectroscopy in the active potential where the cathodic hydrogen is charged from two models of transients. Tests performed using an electrochemical chaos analyzer simplify the expertise of the palladium cathode in focusing on the blocking diffusion of hydrogen. A complex electrical circuit of chaos is considered for adsorption and the blocking diffusion. Depending on the active potential, distinct behavior such as the transformation of transients and limited diffusion can occur. Phase-space spectra are obtained, and synchronization has been developed to clarify the chaos leading to the cracking of palladium. By applying these different analytical tests for the restricted diffusion, it is possible to interpret the processes from the power spectra, autocorrelation function, or the divergence coefficient in the region of active potentials. Analyzers can detect flaws in this hydrogen diffusion process and suggest corrective measures.

Corrosion Monitoring in Atmospheric Conditions: A Review

A variety of techniques are available for monitoring metal corrosion in electrolytes. However, only some of them can be applied in the atmosphere, in which case a thin discontinuous electrolyte film forms on a surface. In this review, we describe, evaluate and compare both traditional and state-of-the-art real-time corrosion monitoring techniques to identify those suitable for atmospheric conditions. For atmospheric corrosion monitoring (ACM), electrochemical impedance spectroscopy (EIS), electrochemical noise (EN), electrical resistance (ER) probes, quartz crystal microbalance (QCM), radio-frequency identification sensors (RFID), fibre optic corrosion sensors (FOCS) and respirometry, the underlying principles, characteristics and application examples are described, and their advantages and drawbacks outlined. Finally, the techniques are compared in terms of their sensitivity, ease of setup, data processing, ability to identify underlying corrosion mechanisms and applicability in different fields of atmospheric corrosion protection and research.

Review about the Application of Fractal Theory in the Research of Packaging Materials

The work is intended to summarize the recent progress in the work of fractal theory in packaging material to provide important insights into applied research on fractal in packaging materials. The fractal analysis methods employed for inorganic materials such as metal alloys and ceramics, polymers, and their composites are reviewed from the aspects of fractal feature extraction and fractal dimension calculation methods. Through the fractal dimension of packaging materials and the fractal in their preparation process, the relationship between the fractal characteristic parameters and the properties of packaging materials is discussed. The fractal analysis method can qualitatively and quantitatively characterize the fractal characteristics, microstructure, and properties of a large number of various types of packaging materials. The method of using fractal theory to probe the preparation and properties of packaging materials is universal; the relationship between the properties of packaging materials and fractal dimension will be a critical trend of fractal theory in the research on properties of packaging materials.

Electrochemical Noise Measurements of Advanced High-Strength Steels in Different Solutions

Advanced high-strength steels (AHSS), are commonly used in the manufacture of car bodies, as well as in front and rear rails, and safety posts. These components can be exposed to corrosive environments for instance, in countries where de-icing salts are used. In this work, the corrosion behavior of four AHSS steels with dual-phase [ferrite-martensite (DP) and ferrite-bainite (FB)] steels were studied by means of electrochemical noise (EN) measurements according to the ASTM G199-09 standard in NaCl, CaCl2 and MgCl2 aqueous solutions at room temperature. The direct current (DC) trend data from EN were removed by a polynomial method of statistical and spectral analysis. According to the noise resistance (Rn) values obtained for the DP and FB dual-phase steels, both the martensite/bainite content and morphology of the phase constituents have an important effect on the corrosion behavior of these steels. The L.I. (localization index) (0.00054 to 0.15431), skewness (−6.18 to 7.35) and kurtosis (high values 37.15, 74.84 and 106.52) were calculated. In general, the results indicated that the main corrosion process is related to uniform corrosion. Corrosion behavior of AHSS steels exposed in NaCl solution could be related to the morphology of the phase constituents exposed in NaCl, CaCl2 and MgCl2 solutions.

Short-Term Load Interval Prediction Using a Deep Belief Network

In load predication, point-based forecasting methods have been widely applied. However, uncertainties arising in load predication bring significant challenges for such methods. This therefore drives the development of new methods amongst which interval predication is one of the most effective. In this study, a deep belief network-based lower–upper bound estimation (LUBE) approach is proposed, and a genetic algorithm is applied to reinforce the search ability of the LUBE method, instead of simulated an annealing algorithm. The approach is applied to the short-term load prediction on some realistic electricity load data. To demonstrate the effectiveness and efficiency of the proposed method, it is compared with three state-of-the-art methods. Experimental results show that the proposed approach can significantly improve the predication accuracy.

Correlation between the corrosion rate and electrochemical noise energy of copper in chloride electrolyte

An electrochemical noise technique has been applied to describe the corrosion process of copper. The results show that the sampling frequency clearly changes both the energy distribution plot and the power spectral density spectra, which should be taken into consideration strictly and logically before an electrochemical noise test. The corrosion energy, (E_c), deduced using the fast wavelet transform method showed a similar variation trend with corrosion rate. Hence, the proposed parameter E_c represents the corrosion rate or severity.

Sampling frequency clearly changes EDP and PSD spectra and EN corrosion energy shows a similar variation trend with corrosion rate.