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The purpose of this study is to investigate cathodic protection (CP) efficiency in the tidal zone and its associated processes.

Specific features of CP in the tidal zone, that is, persistence of a thin seawater film and insufficient cathodic potential due to ohmic drop, were addressed. In this preliminary study, carbon steel electrodes were polarized at two cathodic potentials (correct or insufficient protection) while immersed in 1 mm or 5 mm thick natural seawater layers. After CP interruption, the protective ability of the layers covering the steel electrodes was studied using various electrochemical methods, including electrochemical impedance spectroscopy. The layers were characterized by XRD.

The protective ability of calcareous deposits was increased in thin seawater films. Insufficient CP could promote protective aragonite/corrosion products layer.

The combined effects of thin seawater film and applied potential were never addressed, and the conclusions drawn from this preliminary study give new insight on the efficiency of CP in the tidal zone.

This study aims to evaluate the protection performance of zinc as sacrificial anode for ABS A steel in the presence of H₂S under different temperatures, pH and salinities.

In this paper, weight loss measurements and electrochemical measurements are used to evaluate the corrosion degree of zinc and ABS A steel.

Under the conditions involved in this work, it is shown that zinc is a nice sacrificial anode with the reason of its stable potential and excellent anode current efficiency according to the relevant standard. And it is also found that the hydrogen evolution does not occur on ABS A steel specimens. The potential difference between cathode and anode is suitable; thus, it can be concluded that each steel is well protected.

To the best of the authors’ knowledge, no other study has analyzed the protection mechanism and effect of zinc as sacrificial anode in H₂S-containing environments under high temperature at present.

The low carbon steel used in industrial water conveying pipes in the Dora refinery is corroded. This study aims to reduce corrosion rate in these pipes by using green inhibitor extracted from dill plant. This inhibitor is sustainable environmentally.

The inhibitor extracted from the dill plant was added at different temperatures (25, 40, 60 and 80°C) and at a fixed concentration of 1,400 ppm, as the best protection was obtained at this concentration. The study was carried out under the same conditions using a polarization technique and scanning electron microscope.

From the results obtained from the polarization curves, it was found that the inhibition efficiency was 92.12% at a concentration of 1,400 ppm and a temperature of 20°C. Potentiodynamic curves showed that both cathodic and anodic reactions were affected by the addition of the inhibitor, indicating that the used inhibitor acted as a mixed type inhibitor, which means that the addition of these inhibitors to the industrial water reduced the anodic dissolution of iron and also retarded the cathodic hydrogen evolution reaction. This reveals that the inhibition mechanism is of the mixed type with a predominant anodic reaction. The results of the fourier transform infrared test indicated that the dill plant contained different chemical bonds (C–H, C = O, S = O, N–O and C–N) that were included in the construction of the barrier layer to protect the steel surface from corrosion.

The dill plant is abundant in nature, its cost is low and its extraction is very easy. It can be used as an environmentally friendly inhibitor to reduce the rate of corrosion in water-carrying pipes used in oil refineries because it contains effective groups (aromatic rings) that combine with metal atoms to form strong bonds that stick to the surface of the metal, which protect it from the attack of the corrosive medium.

Reliability centered maintenance (RCM) is a process used to determine activities to be taken to ensure an asset continues to perform asset's function in asset's present operating context by identifying asset's function, failure modes that could preclude performing asset's intended function, prioritizing failure modes and determining effective preventative maintenance tasks that can be cost effectively and efficiently implemented to reduce the likelihood of a failure.

A comprehensive survey of literature was undertaken to examine the current industry state of practice. Various industries were examined to better understand applications of RCM within the various industry sectors and determine those industries that RCM has not historically been readily adopted. A case study example of RCM applied to radial gates for water control in open channel canals for water conveyance is presented to demonstrate a civil infrastructure application.

The results found that RCM has been used since RCM's inception in the airline industry during the 1960s to reduce the cost of maintaining aircrafts. Over the past 40 years, an assortment of industries has begun implementing cost effective preventative maintenance tasks identified during RCM analysis. However, there is a noticeable lack of civil assets being analyzed by RCM, such as water conveyance systems and other civil infrastructure systems vital to the health and well-being of today's societies.

The comprehensive literature review of the current state of practice will provide a better understanding of the various applications of RCM to facilitate RCM's application to other industries, thereby reducing failure due to early identification of maintenance tasks. An example RCM demonstrates the application to a radial gate, used in water conveyance for the drinking water and irrigation sectors, which have not historically used RCM for developing maintenance strategies.

The restoration and strengthening of QT600 is an industry bottleneck challenge. The Co-12 cladding layer has great wear and corrosion resistance. The purpose of this paper is to quantitatively reveal the transient evolution law of the corrosion process of Co-12 cladding layer on QT600 surface.

In this paper, a three-dimensional numerical model of the corrosion process of Co-12 cladding layer by QT600 laser cladding is established. The interaction between pitting pits and corrosion medium is considered to reveal the transient evolution of ion concentration, electrode potential, pH and corrosion rate at different locations.

The calculation shows that the ion concentration in pitting pit changes Cl⁻>Co²⁺>Na⁺, pH value decreases from top to bottom and corrosion rate at bottom is greater than that at top. The electrochemical corrosion test of Co-12 cladding layer was carried out. It is shown that the current density of QT600 increases by an order of magnitude compared to the Co-12 cladding layer, and the corrosion rate is 4.862 times higher than that of the cladding layer.

The results show that Co-12 cladding layer has great corrosion resistance, which provides an effective way for QT600 protection.

The purpose of this paper is to study the effect of temperature on Zn–Ni alloys in ChCl–Urea.

Based on cyclic voltammetry experiments, the deposition behavior and kinetics of the Zn–Ni alloy are studied. The nucleation process of the Zn–Ni alloy is studied in detail via chronoamperometry experiments. The effects of the deposition temperature on the microstructure, Ni content and phase composition of Zn–Ni alloy coatings are investigated via scanning electron microscopy and X-ray diffraction (XRD) combined with classical thermodynamics.

The results show that with increasing temperature, the reduction peak shifts toward a more positive electric potential, which is beneficial for the co-electric deposition process, and the diffusion coefficient is estimated. With increasing temperature, the nucleation process of the Zn–Ni alloy becomes a three-dimensional instantaneous nucleation, the typical kinetic parameters are determined using the standard 3D growth proliferation control model and the Gibbs free energy is estimated. The Zn–Ni alloy coatings are prepared via normal co-deposition. With increasing temperature, the degree of crystallinity increases, the coating gradually becomes uniform and compact and the XRD peak intensity increases.

The nucleation process of the Zn–Ni alloy at different temperatures is analyzed. The diffusion coefficient D and Gibbs free energy are calculated. The contribution of the three processes at different temperatures is analyzed. The effect of temperature on the morphology of the Zn–Ni alloy coatings is studied.

As a common form of failure in industry, corrosion causes huge economic losses. At present, with the development of computational techniques, artificial intelligence (AI) is playing a more and more important role in the field of scientific research. This paper aims to review the application of AI in corrosion protection research.

In this paper, the role of AI in corrosion protection is systematically described in terms of anticorrosion materials and methods, corrosion image recognition and corrosion life prediction.

With efficient and in-depth data processing methods, AI can rapidly advance the research process in terms of anticorrosion materials and methods, corrosion image recognition and corrosion life prediction and save on costs.

This paper summarizes the application of AI in corrosion protection research and provides the basis for corrosion engineers to quickly and comprehensively understand the role of AI and improve production processes.

This study aims to investigate NiTi alloys’ characterization and corrosion behaviour produced by two different powder metallurgy (PM) methods.

It was pre-formed under a protective atmosphere at 900 °C under a force of 45 MPa and sintered for 1 h under 10–6 Mbar in an atmosphere-controlled heat treatment furnace at 1,100 °C. The relationship between microstructural properties, SEM, XRD, density, microhardness and corrosion behaviour of pre-alloyed NiTi alloys produced by two different methods with the production method was investigated.

As a result of the studies, TiO, NiTi, NiTi2 and Ni3Ti intermetallics were determined in XRD examinations. The best surface roughness was observed in the mechanically milled (MM’ed) pre-alloyed NiTi alloy compared to the pre-alloyed NiTi alloy mixed with turbula. The corrosion tests performed in 3.5% NaCl solution determined that the MM’ed pre-alloyed NiTi alloy had better corrosion resistance than the pre-alloyed NiTi alloy mixed with turbula. Pitting corrosion was visualized in the SEM images taken from the corrosion surfaces.

Two different PM methods produced pre-alloyed NiTi powders, and the effects of these methods on the mechanical and corrosion resistance of NiTi alloys were systematically investigated for the first time.

This paper aims to investigate the influence of scan speed on the corrosion and tribocorrosion features of the CoCrMoW samples fabricated via the selective laser melting (SLM) process.

CoCrMoW samples were produced by SLM at different scan speeds. Produced samples were made via structural surveys (X-ray diffraction examinations and scanning electron microscopic analyses), hardness measurements and electrochemical and tribocorrosion experiments.

Outcomes displayed that the corrosion and tribocorrosion properties of CoCrMoW alloy were significantly influenced by scanning speeds. Also, these properties of the alloy increased with increasing scanning speeds. CoCrMoW samples produced at a laser scan speed of 1,000 mm/s showed the best resistance to corrosion and tribocorrosion. This could be related to the high hardness and low grain structure of the fabricated samples.

This paper may be a practical reference and offers insight into the effect of scanning speeds on the increase of hardness, tribological and corrosion performance of CoCrMoW alloys. This study can help in the further advancement of cobalt-chromium alloy in situ produced by SLM for both electrochemical and tribocorrosion behavior for biomedical applications.