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We investigated the corrosion properties and transpassive behavior of CrMnFeCoNi and CrCoNi multi‐principal element alloys (MPEAs) in a 0.1 M NaCl electrolyte at pH 12. By using SECM‐based tip substrate voltammetry (TSV) in combination with the chemical analysis of the electrolyte, we were able to differentiate between anodic metal dissolution and oxygen evolution in the transpassive range. Our investigations have shown that CrCoNi has a significantly higher corrosion resistance compared to CrMnFeCoNi. In the studied alkaline environment, a transpassive oxide film is formed on the surface of CrCoNi during secondary passivation. This transpassive oxide film appears to play a significant role in oxygen evolution, as the increase in TSV currents at the microelectrode coincides with the corresponding current density plateau of the voltametric current trace. The formation of the transpassive oxide film was not observed in previous studies conducted in acidic environments. Moreover, the alkaline electrolyte induced a positive hysteresis and mild pitting corrosion, in addition to intergranular corrosion, which was the sole corrosion process observed at acidic pH levels. These findings enhance the understanding of the processes governing the transpassivity of CrMnFeCoNi and CrCoNi MPEAs in alkaline environments and have potential implications for the development of application‐tailored corrosion‐resistant MPEAs. [ABSTRACT FROM AUTHOR]

Guided wave tomography is an effective non-destructive method for mapping corrosion damage in thin-walled metal structures. Its efficiency and accuracy depend on the choice of a suitable forward model and inversion method. Current techniques mainly use acoustic forward models that, while computationally efficient, are approximate and fail to accurately represent wave propagation in physical experiments, making them less suitable for inversion. This study investigates the performance of Mindlin plate theory, which accounts for through-thickness shear deformations, enabling the modeling of flexural modes in a two-dimensional (2-D) plane. The scattering of A 0 mode Lamb waves from defects of varying depth, width, and shape is analyzed using finite difference and pseudospectral simulations for 2-D and three-dimensional (3-D) defects, respectively. Results from the Mindlin model are compared to finite element model simulations. It is found that Mindlin plate theory accurately represents smooth defect scattering, but is less accurate for sharp-edged defects. [ABSTRACT FROM AUTHOR]

Background: Orthodontics is a speciality of dentistry that uses a plethora of devices made from myriad materials to manage various malocclusions. Prolonged contact of orthodontic appliances with oral tissues can lead to cellular damage, highlighting the need for biocompatible materials to mitigate health risks. Objectives: To analyze the genotoxicity and cytotoxicity produced by metal brackets and coated metallic brackets with polymeric and nanoparticle coatings in oral mucosal cells. Materials & methods: The current study compares the toxicity of 3 different types of orthodontic brackets with control groups of oral mucosal cells. Each of the three treatment groups consisted of 10 samples of orthodontic brackets: stainless steel brackets(Group 1), nanoparticle-coated brackets(Group 2), and polymeric-coated brackets(Group 3) exposed to corrosion eluates employing an oral biomimicry model. Two types of oral mucosal cells- Human Gingival Fibroblasts and Buccal Epithelial Cells were used to study the cytotoxic and/or genotoxic effects of the elutes. Intergroup comparisons were conducted using one-way analysis of variance, while scanning electron microscopy evaluated surface characteristic. Results: The interaction between metal ions and oral mucosal cells showed no statistically significant difference for toxicity assays between the three groups(p > 0.005). However, polymeric and nanoparticle-coated groups showed reduced cellular differentiation when compared with conventional stainless-steel brackets. Conclusion: This in-vitro study shows that polymeric or nanoparticle coating of conventional metal brackets aids in enhancing corrosion-resistant characteristics of orthodontic appliances and reduces the toxic oral environment created by metal release in the oral cavity. [ABSTRACT FROM AUTHOR]

The electrochemical corrosion behavior of Mg-3Sn-2Al-1Zn-(0.6Nd/0.6Y) alloy in 3.5 wt.% NaCl solution under different heat treatment processes was investigated via electrochemical test, immersion weight loss test, and microstructure observation. The results show that the corrosion mechanism of Mg-3Sn-2Al-1Zn-(0.6Nd/0.6Y) alloy is similar to that of pure magnesium, which is the process of electrochemical reaction between magnesium and water to generate magnesium hydroxide and hydrogen gas. The solid solution treatment by holding at 400 °C for 24 h significantly improved the corrosion resistance of Mg-3Sn-2Al-1Zn-(0.6Nd/0.6Y) alloys. Nd/Y is formed intermetallic compounds with Mg and Al to increase the corrosion resistance of Mg-3Sn-2Al-1Zn alloy. However, the effect of adding Nd was not as excellent as that of Y, and the solid solution Mg-3Sn-2Al-1Zn-0.6Y alloy exhibited the best corrosion resistance. [ABSTRACT FROM AUTHOR]

Magnesium and its alloy continue to grow as a material in automotive industries, because of their efficiency and ability to improve the power-to-weight ratio of transportation. Depending on the environmental conditions, magnesium can be subjected to varying degrees of atmospheric corrosion, as it is directly exposed to atmospheric conditions. Atmospheric corrosion behavior of AZ31B Magnesium in urban and rural environments was investigated in Indonesia. The test was carried out for 1, 2, and 4 months. Mass loss measurement results show that the longer the exposure time, the higher the atmospheric corrosion rate of the AZ31B alloy. In addition, the corrosion rate in the Mg AZ31B specimen in urban environment (ITB) tends to be higher than the corrosion rate in rural environment (Bosscha) related to the different in temperature. The corrosion product that formed on the specimen's surfaces was also thoroughly characterized. SEM, FTIR, and XRD were used to observe the corrosion product. Additionally, using open circuit potential, potentiodynamic polarization, and electrochemical impedance spectroscopy, the specimen's corrosion resistance was investigated using an electrochemical method in solutions of NaCl, Na2SO4, and NaCl + Na2SO4 to simulate atmospheric corrosion environment. [ABSTRACT FROM AUTHOR]

As aging infrastructures raise public concerns, evaluating their performance is crucial for maintaining structural integrity, especially for corroding prestressed concrete members. These structures may experience substantial tendon cross‐sectional area loss before any visible deterioration becomes detectable. While various non‐destructive techniques (NDT) have proven effective in labs, correlating corrosion‐induced damage in field members remains a challenge. Establishing these correlations is key for understanding the overall performance of aging structural concrete elements and ensuring their continued safe operation through non‐invasive means. This paper investigates various NDTs on a concrete bridge deck, aiming to correlate results. Visual inspection, Schmidt rebound hammer, Ultrasonic Pulse Velocity (UPV), corrosion detection techniques, Ground Penetrating Radar (GPR), Ultrasonic Pulse Echo (UPE), and Impact Echo (IE) methods are evaluated for detecting concrete deck damage. Results show the methods' capabilities in detecting defects to a certain extent, highlighting their potential in assessing aging concrete infrastructures. [ABSTRACT FROM AUTHOR]

Laser cladding technology is an advanced surface modification technique that has gained significant attention in various fields due to its energy savings, efficiency, and environmental friendliness. This paper discusses the preparation of AlCoCrFeNi high‐entropy alloy (HEA) coatings on the surface of a 5083 aluminum alloy using laser cladding technology under the Ar gas conditions. An orthogonal test system was used to optimize the laser cladding process parameters. The microstructure, as well as the mechanical, frictional, and electrochemical properties of the HEA coatings, were comparatively analyzed under the two process conditions S4 and S10. The results indicate that, under S10, the HEA coatings exhibit optimal surface quality. The coatings contained a mixture of Face‐centered cubic (FCC) and Body‐centered cubic (BCC) phases. Microscopic examination revealed three distinct areas: dark, gray, and off‐white. The coatings can significantly improve the wear and corrosion resistance of the alloy substrate. For the best results, it is set the laser power to 200 W, the laser scanning distance to .05 mm, and the laser scanning rate to 1250 mm/s. This present study offers a novel technical foundation for the fabrication of HEA coatings. [ABSTRACT FROM AUTHOR]

Schiff bases are important in corrosion inhibition due to their ability to form stable complexes with metal ions and create protective layers on metal surfaces, thereby extending the lifespan of structural materials in various industrial applications. In this study the Salicylideneaniline and its derivatives were analyzed as corrosion inhibitor versus mild steel corrosion via DFT analysis. The eight molecules were chosen; salicylideneaniline, 2-(benzylideneamino)phenol, 4-(benzylideneamino)phenol, 2-phenyldiazenylphenol, 2-Phenylazo-4-methylphenol, 3-methyl-2-phenyldiazenyl phenol, 2-[(2-methylphenyl)diazenyl]phenol, 4-phenyldiazenylbenzene-1,3-diol), for this purpose. The Gaussian 03 program and the 6-311++G (d, p) basis set was used. Electronic properties such as the energy of the highest occupied molecular orbital (EHOMO), energy of the lowest unoccupied molecular orbital (ELUMO), energy gap (ΔE) between LUMO and HOMO, dipole moment, and charges on the backbone atoms, ESP were determined. [ABSTRACT FROM AUTHOR]

Molten chloride salts represent a very corrosive medium due to the amount of impurities they contain and that essentially comes from moisture. In this work, an industrial nickel-based alumina-forming alloy was preoxidized and corroded for 500 h in the NaCl–MgCl2 eutectic. Electrochemistry and SEM analyses were used to prepare and analyse the corrosion test. Both the nickel-rich matrix and the alumina scale formed during preoxidation seemed to remain stable during the corrosion test contrary to some of the chromium carbides initially present in the columnar microstructure of the alloy. The use of X-ray tomography coupled with SEM observation revealed a preferential dissolution of the chromium carbides connected to the alloy/salt interface. X-ray tomography reveals a chromium carbides network enabling a deep molten salt infiltration within the alloy due to their preferential dissolution. Molten salt infiltration in the dissolved carbides network then leads to the oxidation of aluminium present in the alloy into a mixed MgAl2O4 spinel. An oxoacido-basic reaction between the alumina scale formed at the alloy surface during preoxidation and MgO dissolved in the salt is also discussed. This work shows that nickel-based alumina-forming alloy present a realistic interest and that the microstructure of the alloy should be optimized in further work to enhance corrosion resistance. [ABSTRACT FROM AUTHOR]

Samples of the Ni-based superalloy, RR1000, were exposed to 98% Na2SO4/2% NaCl salts at 700 °C with a flux of 1.5 µg cm−2 h−1 in flowing air + 300 ppm SO2 for a total of 250 h. Three pre-exposure conditions were studied: a bare reference alloy; fast heating to the test temperature followed by a 100 h hold; heating at a rate of 5 °C min−1 to the test temperature following by a 100 h hold. The surface oxide formed under the latter two conditions were Cr2O3 or NiCr2O4, respectively. The results show corrosion pit formation on the surface of the base, reference sample, and no pits present on the sample with the preformed Cr2O3. Some protection was found for the sample heated at 5 °C min−1 with a delay in the progression to accelerated corrosion attack. Additional testing under moisture containing air was also conducted. This showed no obvious difference in surface oxide morphology under the two tested heating rates for the short-term exposures examined but a difference was noted to be dependent on the moisture content of the air. [ABSTRACT FROM AUTHOR]

Microbially influenced corrosion represents a critical challenge to the integrity and durability of carbon steel infrastructure, particularly in environments conducive to biofilm formation by nitrate-reducing bacteria (NRB). This study investigated the impact of NRB biofilms on biocorrosion processes within oil/water recovery operations in Algerian pipelines. A comprehensive suite of experimental and analytical techniques, including microbial analysis, gravimetric methods, and surface characterization, were employed to elucidate the mechanisms of microbially influenced corrosion (MIC). Weight loss measurements revealed that carbon steel samples exposed to injection water exhibited a corrosion rate of 0.0125 mm/year, significantly higher than the 0.0042 mm/year observed in crude oil environments. The microbial analysis demonstrated that injection water harbored an average of (4.4 ± 0.56) × 106 cells/cm2 for sessile cells and (3.1 ± 0.25) × 105 CFU/mL for planktonic cells, in stark contrast to crude oil, which contained only (2.4 ± 0.34) × 103 cells/cm2 for sessile cells and (4.5 ± 0.12) × 102 CFU/mL for planktonic cells, thereby highlighting the predominant role of injection water in facilitating biofilm formation. Contact angle measurements of injection water on carbon showed 45° ± 2°, compared to 85° ± 4° for crude oil, suggesting an increased hydrophilicity associated with enhanced biofilm adhesion. Scanning electron microscopy further confirmed the presence of thick biofilm clusters and corrosion pits on carbon steel exposed to injection water, while minimal biofilm and corrosion were observed in the crude oil samples. [ABSTRACT FROM AUTHOR]

There has been a good deal of research on improving the corrosion behavior of magnesium (Mg) by polycaprolactone (PCL) coating, albeit with destroying bioactivity and hydrophilicity. The adhesion of a polymeric layer to the surface of the metal is also a knotty problem. On the other hand, the micro-arc oxidation (MAO) process is a new method that can create thin films with desirable adhesion to the surface of the implants although these films could hardly control the degradation of Mg. In this research, a multifunctional nanocomposite coating showing significant adhesion to the surface of the substrate has been fabricated that can enhance not only the corrosion but also the bioactivity of Mg-based biomaterials. It can also improve their biological, antibacterial, and osteogenesis properties. The fabrication process of this multifunctional composite coating with these desirable features can be broadly separated into three main stages beginning with synthesizing strontium (Sr) and copper (Cu) doped bioactive glass nanoparticles (BGNs), applying micro-arc oxidation (MAO) nanocomposite coating on the surface of pure Mg, and finally sealing the pores of MAO layer by PCL with BGNs containing Sr and Cu at concentrations of 5, 10, and 15 wt%. After this process, the corrosion resistance, bioactivity, antibacterial, and cytotoxicity of Mg-based samples were assessed. It was found that the addition of 10 wt% of BGNs in the MAO-PCL nanocomposite enhanced corrosion resistance (78,343.358 KΩ.Cm2), bioactivity, cellular viability and antibacterial property (99%) of Mg-based scaffolds, which can be widely used in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Partially phosphorylated poly(vinyl alcohol) (PPVA) as anticorrosive coating for AZ31 magnesium alloy was investigated in Hank's Balanced Salt Solution (HBSS). Four phosphoric acid levels were used to modify PVA, resulting in four PPVA products. They were characterized using thermogravimetric analysis (TGA), water contact angle (WCA), and swelling test. PPVA-coated Mg alloys were evaluated using hydrogen evolution, cathodic polarization, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). TGA indirectly revealed crosslinked regions in the PPVA structure that increased with acid content. WCA and hydrogen evolution tests suggested that PPVA is a promising polymer for biomedical applications. Corrosion tests showed that the PPVA with 10% acid addition significantly improved the impedance modulus and lowered the cathodic kinetics compared to uncoated samples. The findings of the study suggested that the acid addition in PVA must be at least 10 % to guarantee improved corrosion resistance in HBSS, which indicates this material has potential for biological applications. [ABSTRACT FROM AUTHOR]

Aluminum alloys, characterized by their low density and high mechanical strength, are widely applied in the manufacturing sector. However, the application of aluminum alloys in extreme environments presents severe corrosion challenges. Sol–gel organic coating techniques have garnered significant attention due to their excellent stability, barrier properties, and cost-effectiveness, as well as their simpler processing. Nevertheless, conventional sol–gel coatings are unable to withstand the corrosive effects of high-chloride and high-halide ion environments such as marine conditions, owing to their inherent structural defects. Therefore, this study proposes the utilization of a simple method to synthesize catechol (CA) and meta-phenylenediamine (MPD)-derived catecholamine compounds to modify sol–gel coatings. Surface characteristics of the modified coatings were analyzed using Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The thickness of the modified coating was approximately 6.8 μm. The CA/MPD-modified substance effectively densifies the sol–gel coating, enhancing its corrosion protection performance. A 3.5 wt% NaCl solution was used to simulate a marine environment, and electrochemical impedance spectroscopy (EIS) was conducted using an electrochemical workstation to evaluate the coating's protective properties over a long-term period. The results indicate that the modified coating provides protection for 3003 aluminum alloy for a minimum of 30 days under corrosive conditions, outperforming unmodified sol–gel coatings in terms of corrosion resistance. [ABSTRACT FROM AUTHOR]

Acoustic emission (AE) testing is used for the continuous evaluation of structural integrity and the monitoring of damage evolution in structural components and materials. During operation, the environmental and loading conditions of metal structures can result in corrosion and surface wear damage. The early detection of surface degradation flaws is crucial, as they can serve as local stress concentration points, leading to crack initiation and failure. In this work, the effectiveness of AE in monitoring corrosion and surface wear flaw formation was experimentally evaluated. AE sensors were installed on steel test plates during the artificial induction of corrosion and surface wear in order to detect and record the generated AE signals. Corrosion-related AE signals typically exhibit low amplitude, count, and energy values. The direct detection of active corrosion can be challenging in noisy environments, but it can be carried out under certain conditions using dedicated AE sensor groups. Surface-wear-related AE signals exhibit high amplitude, energy, and count values, with long duration values that are associated with wear and grinding conditions. It was found that AE sensors can be utilised to detect corrosion and surface degradation events. The effectiveness of the AE method in detecting surface degradation in noisy environments can be improved by implementing a filtering methodology. This will limit the recording of noise-related signals that can mask out actual surface degradation AE events. [ABSTRACT FROM AUTHOR]

This study investigates the impact of strontium (Sr) additions on the corrosion resistance of an LM6 (A413) aluminium alloy. By incorporating varying concentrations of Sr (0.01 wt.% and 0.05 wt.%), the morphological and corrosion behaviours of the alloy were analysed under different corrosive environments, including sulphuric acid, sodium hydroxide, and sodium chloride solutions. The results demonstrate that Sr modifications significantly enhance the alloy's corrosion resistance, with the most substantial improvement observed at 0.05 wt.% Sr. The analysis revealed that the weight loss of the alloy in sulphuric acid decreased by 2.5% with 0.05 wt.% Sr after 10 days of immersion, due to the formation of a stable passive oxide layer. In sodium hydroxide, however, the weight loss was reduced by 5% with 0.05 wt.% Sr after 10 days, indicating aggressive uniform corrosion. In the 3.5% sodium chloride solution, the corrosion rates remain relatively low, and the 0.05 wt.% Sr alloy showed a decrease in corrosion product formation over time, suggesting enhanced resistance. Detailed surface analyses, including 3D profiling and morphology assessments, revealed that Sr additions refine the eutectic silicon phase, transforming it from a coarse to a more desirable fibrous or lamellar structure, thus improving the alloy's overall performance. The innovative findings underscore the potential of Sr as an effective microstructural modifier for enhancing the durability and longevity of Al-Si alloys in corrosive environments. [ABSTRACT FROM AUTHOR]

In this paper, flexible conductive composite materials were prepared from flexible graphite and carbon fiber by mould pressing, and their micromorphology was studied by SEM. The influence of carbon fiber content on the mechanical properties and electrical conductivity of the flexible conductive composite material was studied, and the corrosion rate of the flexible conductive composite material coupling with galvanized steel in soil with different SO42− concentrations was studied. The results showed that the tensile strength reached 5.82 MPa when the mass ratio of carbon fiber to flexible graphite was 1:20, and the volume resistivity achieved 4.76 × 10−5 Ω·m when the mass ratio of carbon fiber to flexible graphite was 1:30. With the increase in molding pressure, tensile strength and electrical conductivity had a slight increase. When the flexible conductive composite material was coupled with galvanized steel, sulfate could accelerate the galvanic cell corrosion between the flexible graphite grounding material and galvanized steel. The increase in the sulfate concentration led to more corrosion acceleration. With the increase in corrosion time, the corrosion potential of the flexible graphite grounding material and galvanized steel coupling body decreased to its lowest at 30 days, and then increased gradually. The corrosion current was the highest at 30 days, and then decreased gradually. [ABSTRACT FROM AUTHOR]

Laser-welding is a promising technique for welding NiTi shape memory alloys with acceptable tensile strength and comparable corrosion performance for biomedical applications. The microstructural characteristics and localized corrosion behavior of NiTi alloys in a simulated body fluid (SBF) environment are evaluated. A microstructural examination indicated the presence of fine and equiaxed grains with a B2 austenite phase in the base metal (BM), while the weld metal (WM) had a coarse dendritic microstructure with intermetallic precipitates including Ti2Ni and Ni4Ti3. The hardness decreased from the BM to the WM, and the average hardness for the BM was 352 ± 5 HV, while it ranged between 275 and 307 HV and 265 and 287 HV for the HAZ and WM, respectively. Uni-axial tensile tests revealed a substantial decrease in the tensile strength of NiTi WM (481 ± 19 MPa), with a reduced joint efficiency of 34%. The localized corrosion performance of NiTi BM was superior to the WM, with electrochemical test responses indicating a pitting potential and low corrosion rate in SBF environments. The corrosion rate of the NiTi BM and WM was 0.048 ± 0.0018 mils per year (mpy) and 0.41 ± 0.019 mpy, respectively. During welding, NiTi's strength and biocompatibility properties changed due to the alteration in microstructure and formation of intermetallic phases as a result of Ti enrichment. The performance and safety of welded medical devices may be impacted during welding, and it is essential to preserve the biocompatibility of NiTi components for biomedical applications. [ABSTRACT FROM AUTHOR]

In this work, leaves of Silybum marianum (L.) Gaertn were extracted by a one-step extraction method using ethanol as a solvent, and the Silybum marianum (L.) Gaertn extract (SMGE) was firstly employed as a green corrosion inhibitor for carbon steel in 0.5 mol/L H2SO4. The corrosion inhibition performance was studied using weight loss and electrochemical methods, and the anti-corrosion mechanism of SMGE is further analyzed through some surface characterizations and theoretical calculations. The results indicate that SMGE can act as a mixed-type corrosion inhibitor and possess superior corrosion inhibition performance for carbon steel in H2SO4 solution, and the optimum corrosion inhibition efficiency reached 93.06% at 800 ppm SMGE combined with 60 ppm KI. The corrosion inhibition efficiency increased with the rising inhibitor concentration. Surface characterizations illustrated that the inhibitor could physico-chemically adsorb on a metal surface, forming a hydrophobic, protective film. [ABSTRACT FROM AUTHOR]

The mechanical properties and electrochemical stability of high-entropy alloys are substantially affected by their composition distribution and crystal structure. However, the details concerning the conditions of milling and sintering for sintered alloys have rarely been reported. In this work, a series of CrMnFeCoNi alloys were fabricated by ball milling and spark plasm sintering for different periods. Their crystal structure, density, hardness, and corrosion resistance were investigated. As a result, a partial alloying of Cr, Mn, Fe, Co, and Ni was achieved by ball milling. However, Cr-rich particles, including Mn, were formed in the milled powders. The sintered alloys inherited the Cr-rich particles to form Cr-rich zones. The formation and change of chromium carbide were also confirmed in sintered alloys. Extended milling or sintering to 12 h achieved high hardness and corrosion resistance for the sintered alloys. The Cr-rich zones showed high hardness and Kelvin potential, which affect both the hardness and the corrosion resistance. [ABSTRACT FROM AUTHOR]

The corrosion behavior of steels of various grades in sulfuric acid solutions with the addition of nitrogen-containing corrosion inhibitors has been studied. Compounds containing the 1,2,4-triazole moiety effectively protect low-carbon (St3, St20, 08PS), high-strength (70S2KhA), and stainless steels (1Kh18N9T) not only from corrosion but also from the hydrogen penetration into the metals in concentrated sulfuric acid solutions. In some cases, the degree of steel protection from corrosion by these compounds exceeded 99%. The possibility of creating mixed inhibitors for steel protection containing triazole derivatives and KI has been shown. The rate constants for the main steps of cathodic evolution and hydrogen penetration into steel in sulfuric acid solutions have been determined, and the subsurface concentrations of hydrogen in the metals have been calculated. Triazole derivatives were found to act as inhibitors of hydrogen absorption by steel in H2SO4 solution. The degree of protection of steel from hydrogen absorption can reach 97%. It has been shown that triazole derivatives act as complex inhibitors of steel corrosion in sulfuric acid solutions because, along with strong inhibition of metal corrosion, they prevent hydrogen absorption by steel. [ABSTRACT FROM AUTHOR]

The corrosion and material evaluation study in (a) water‐based simulated black liquor and (b) water‐based simulated black liquor at super‐critical conditions was successful. The conclusion from the testing program was that the most resistant alloy for the defined conditions is the chromium‐rich carbon steel candidate P91 (UNS K91560). This is a type of creep strength‐enhanced ferritic alloy, which is steel designed to retain strength at high temperatures. The P91 abbreviation represents the material's chemical composition, that is, 9 wt% chromium (Cr) and 1 wt% molybdenum (Mo). Further work is required to conclude the corrosion resistance for the P91 quality at supercritical conditions in the welded condition and to better understand caustic corrosion mechanisms. [ABSTRACT FROM AUTHOR]

In the present study, the effect of varying titanium dioxide (TiO2) nanoparticles on the dielectric, thermal, and corrosion characteristics of PI-based composites prepared by spark plasma sintering was investigated. The results obtained revealed that the TiO2 nanoparticles were uniformly dispersed within the PI matrix. Addition of TiO2 into the neat PI markedly reduced its dielectric constant and electrical conductivity by 72.7% and 82.3%, respectively, as well as enhancing its breakdown strength by 16.7% at 8 wt% TiO2 loading. The nanocomposites depict better thermal stability and heat-resistance index characteristics when compared to the PI. Additionally, the produced nanocomposites exhibit improved corrosion resistance than that of the neat PI. The remarkable improvement in the dielectric, thermal stability, and corrosion resistance of the nanocomposites is achieved by better dispersion of the TiO2 particles in the polymer matrix. The enhancement in properties suggests TiO2/PI-based nanocomposites potential for a variety of applications in electrical insulation, thermal management, and harsh environment. [ABSTRACT FROM AUTHOR]

Corrosion is one of the most significant problems in irrigation systems, and fertigation may increase its damage. One of the solutions to mitigate this phenomenon would be using cathodic protection combined with piping coating, so it is essential to evaluate the type of sacrificial anodes and the cathode/anode area ratio, variables that change the performance of cathodic protection and its application cost. Thus, this study aimed to validate the effect of Al anodes on the protection against the mass loss of galvanized steel used in fertigation with white KCl solution at 10 g L−1 and verify the influence of the cathode/anode area ratio on the galvanized steel protection and anode consumption. Thus, we conducted immersion tests by simulating 10 years of fertigation to determine the mass loss of the galvanized steel and Al anodes. The results showed that Al anodes significantly reduce the mass loss in galvanized steel exposed to KCl solution, but there is no significant difference in its mass loss with the increase in the cathode/anode area ratio. Regarding the Al anodes, there was also no significant difference in mass loss with the increase in the cathode/anode area ratio. [ABSTRACT FROM AUTHOR]

The effects of chlorides on the corrosion of steel bars within a matrix comprising modified magnesium oxysulfide (MMOS) cementitious materials was investigated. The phase composition, morphology and distribution of steel corrosion products (SCPs) were studied. There was basically no corrosion of the steel bars in the MMOS cement without chlorides. A high chloride content and a high water/cement (w/c) ratio in the MMOS matrix had adverse effects on the steel bar corrosion. The primary SCPs in the MMOS mixes were iron oxyhydroxides (FeOOH) and ferric oxide (Fe2O3), while ferrous oxide (FeO) was only observed at low w/c ratios, indicating a lower degree of oxidation. The presence of di-iron nonacarbonyl (Fe2(CO)9) at high w/c ratios suggested a higher degree of oxidation. At lower w/c ratios, rust products readily diffused. Conversely, at higher w/c ratios, these products accumulated close to the steel bars, resulting in a compact structure. [ABSTRACT FROM AUTHOR]

The durability of concrete under combined acidic exposure and flexural loading was studied. Concrete specimens were made and subjected to up to 168 days of exposure to flexural loading (stress levels of 0, 0.35 and 0.50 of the 28 day flexural strength) and an acidic environment. Concrete properties such as neutralisation depth, mass change, compressive strength and flexural strength were measured. The compositions of different samples were determined by means of X-ray diffraction and chemical analysis and the microstructure of samples was examined using scanning electron microscopy. The results showed that, with an increase in stress level from 0 to 0.50, the performance of the concrete deteriorated gradually and the deterioration in the tension zone was greater than that in the compression zone. The concrete performance improved within 28 days but deteriorated dramatically afterwards. The acidic solution reacted with the cement paste, leading to the formation of harmful gypsum and the decomposition and dissolution of cement hydration products. An increase in stress level increased the porosity of the concrete, accelerating the rate of acid erosion, which led to a deterioration of concrete performance. [ABSTRACT FROM AUTHOR]

The current study investigates the influence of immersion time (7, 14, 21, and 28 days) on the corrosion behaviour of American Petroleum Institute (API) X70 and X80 steel grades in freely aerated simulated concrete pore solution (pH ~ 12 to 13.8) utilizing electrochemical techniques such as electrochemical impedance spectroscopy, linear polarization, and cyclic polarization. The electrochemical results suggest that the corrosion resistance of X70 line pipe steel increases as immersion time increases (from 7 to 28 days) due to the formation of a stable protective oxide layer on the surface. In the case of X80 line pipe steel, however, the corrosion resistance increases as immersion time increases from 7 to 14 days due to the preferential dissolution of bainite as a result of its higher activity, which initiates the formation of passive film. Furthermore, after 21 days of immersion of X80 line pipe steel in simulated pore solution, a considerable decline in corrosion resistance was observed, which indicates de-passivation, as a result of an increase in oxide film thickness and subsequent spalling off. Intriguingly, as compared to X80 line pipe steel, X70 line pipe steel has a greater potential for producing a stable protective oxide layer without the appearance of minor cracks after a 28-day immersion period, thereby preventing further corrosion and enhancing corrosion resistance. [ABSTRACT FROM AUTHOR]

The present study adopts a multi-facet approach to design bio inspired concentrated alloys for potential application as articulating surfaces in joint replacements. A series of equiatomic, Nb rich and Ti rich TiMoNbZr based medium entropy alloys (MEAs) were processed via arc melting and their mechanical, in-vitro corrosion, wear, and in vitro and in vivo biocompatibility were investigated. Equiatomic MEA had primarily bcc with minor hcp phases where the single bcc was achieved with the addition of Nb. The single bcc Nb rich alloy resulted in 13 % elongation, much higher than equiatomic or Ti rich alloy. All the MEAs showed comparatively higher yield strength due to the climb of edge dislocations which is the main rate limiting mechanism at 300 K, as evident molecular dynamics (MD) simulation. The locally fluctuating energy landscape promotes kinks on edge dislocation, and at local minima nanoscale segments gets pinned. Upon yielding the entangled kink leaves a trail of vacancies/interstitials and escapes via climb motion to render high yield strength. The higher corrosion and pitting resistance of Nb enriched alloys can be attributed to the stable ZrO 2 , Nb 2 O 5 , TiO 2 , and MoO 3 oxides, high polarization resistance (106–105 Ωcm−2), and low defect densities (1016–1018). In vitro cell-materials interaction using MC3T3-E1 showed bioinert but cytocompatible nature of the MEAs. The wear rate of the MEAs was in the range of 7–9 × 10−5 mm3N−1m−1. The wear debris did not show any tissue necrosis when implanted in rabbit femur rather new bone regeneration can be seen around the particles. In the present work, a noble Nb enriched MEAs with superior mechanical, in vitro wear, corrosion and cytocompatibility properties was designed for articulating surfaces in joint replacement. • Single bcc in Nb enriched MEAs resulted in 13 % elongation with high hardness and yield strength. • Climb of entangled edge segment is the rate limiting mechanism in controlling high yield strength of MEAs at 300 K. • High polarization resistance (106–105 Ωcm−2), and low defect densities (1016–1018) attributes to ZrO 2 , Nb 2 O 5 , TiO 2 , and MoO 3 oxides enriched passive film. • Wet sliding wear rate ranged in order 7–9 × 10−5 mm3N−1m−1. In-situ generated wear debris when implanted in rabbit femur did not show any tissue necrosis rather new bone regeneration was observed around debris. [Display omitted] [ABSTRACT FROM AUTHOR]

The interest in Nitinol (NiTi) as biomedical material is growing thanks to its unique properties, particularly shape memory and superelasticity. Recently, additive manufacturing (AM) has emerged as an alternative to fabricate superelastic NiTi biomedical parts. However, when using AM to fabricate NiTi parts, a proper heat treatment must follow, recommended not only to alleviate the AM-induced residual stresses, but also to develop a suitable microstructure to enhance the material superelasticity. This heat treatment is expected to modify also the NiTi corrosion behavior, which must be evaluated since corrosion may lead to the possible harmful release of nickel ions in the human environment. In this framework, the objective of the paper is to assess the mechanical and corrosion properties of a Ni-rich NiTi fabricated by laser powder bed fusion before and after heat treatment. To this aim, nano-indentation was used to evaluate superelasticity, whereas electro-chemical tests provided the corrosion potential and current density. The results of the analyses show that both the mechanical and corrosion characteristics were related to the peculiar microstructural features induced by the AM and heat treatment steps, nevertheless ageing at 600°C was the best in terms of superelasticity, while aging at 300°C assured the highest corrosion resistance. [ABSTRACT FROM AUTHOR]

Nickel-based superalloys exhibit exceptional suitability for operating in environments characterized by corrosive agents and elevated temperatures. Strategic allocation of this expensive material solely to the functional surface areas yields significant economic advantages. The poor tribological property profile of Inconel 718 can be significantly improved through a boriding process. In this study, the possibility of combining a coating process with boriding technology and in situ heat treatment was investigated. Layers of Inconel 718 were deposited to an austenitic stainless steel using wire-based electron beam cladding (EBC) and subsequently subjected to boriding. Based on results from annealing experiments, boriding treatments were performed at various temperature/time regimens with the aim of inducing in situ age hardening during boriding. The focus was on the investigation of the influence of the temperature/time regime during boriding on the microstructure and hardness, as well as examining the wear and corrosion behavior of the resulting borided layers. The results showed that the desired target hardness range was achieved after in situ aging with all boriding variants. Furthermore, it was demonstrated that boriding significantly improved the wear resistance but decreased corrosion resistance. [ABSTRACT FROM AUTHOR]

In order to study the fatigue damage of joints in a parallel-type combined highway and railway steel truss bridge, the bridge finite element model containing refined joints as well as the multi-body models of the train and the vehicle is established. The equation of motion for the vehicle-bridge coupled system is solved using Craig-Bampton method. The dynamic weighting system is used to collect annual highway traffic flow data, and the distribution characteristics of parameters, such as vehicle type, speed, vehicle weight and vehicle spacing, are statistically analyzed. Combining the train load model, the fatigue damage of steel truss joints due to the train and vehicle loads is calculated using S-N curve and Miner linear cumulative damage theory, and the fatigue life is predicted using the rain flow counting method. The effects of train speed, load and unevenness on the fatigue damage of steel truss joints are discussed and the development of cumulative fatigue damage and life of the steel truss joints under environmental corrosion is analyzed. The results indicate that the variation of fatigue damage does not show a monotonous trend with increasing train speed. The fatigue damage increases rapidly, and the fatigue life decreases significantly with load increasing or flatness deteriorating. Considering the reduction in the joint stiffness caused by environmental corrosion, the development of cumulative fatigue damage curve is nonlinear, and the fatigue life decreases significantly. [ABSTRACT FROM AUTHOR]

The inhibition effect of pumpkin pod extract (PPE) on the corrosion of stainless steel in 2M HCl has been studied by weight loss technique. The process of inhibition and temperature effects on inhibition efficiency, rate of corrosion, and weight loss were determined with a temperature range of 313K - 353K at 7 hours of dipping. An increase in temperature led to a decrease in both the inhibition efficiency of PPE extract and the rate of corrosion of stainless-steel metal surfaces. Parameters of thermodynamics activation such as; activation energy, enthalpy, and entropy values range from 73.739 - 110.056kJ/mol, 70.936 - 107.252kJ/mol, and 2.7610 - 100.373J/molK respectively. The higher value of activation energy obtained in comparison to the enthalpy of adsorption suggests a physical adsorption mechanism on stainless steel. [ABSTRACT FROM AUTHOR]

In this study, the corrosion behavior and microstructural transformations of 1000 series aluminum and copper tubes after an explosive welding process were investigated. Welding was performed with a fixed stand-off distance and various explosion thicknesses. Explosive welding was carried out using a consistent stand-off distance of 2 mm while varying the thickness of the explosive material of 60 mm (sample 1) and 80 mm (sample 2). The explosion velocity employed during the process was measured at 2504 m/s. Optical and electron microscopy images revealed that the thickness of the melting layer at the interface increases proportionally with the thickness of the explosive charge. Specifically, as the explosive thickness increased from 60 to 80 mm, the thickness of the melting layer increased as well. Also, the resuls of the potentiodynamic polarization test indicated a decrease in the corrosion potential from –670 mV (sample 1) to –665 mV (sample 2) as the explosive material thicknesses increased. At the same time, the corrosion current density rose from 52.34 µA/cm2 (sample 1) to 78.32 μA/cm2 (sample 2). An analysis of the Nyquist diagram for explosive welding samples revealed that the curve radius of sample 2 exceeded that of sample 1, suggesting a higher corrosion resistance in sample 1 compared to that in sample 2. [ABSTRACT FROM AUTHOR]

The rapid breakdown anodization process was used to modify the copper surface. The effects of the chemical solution mechanical movement (CSMM), anode edge isolation, applied voltage, and activity of hydrogen ions in the solution on the morphology of anodized copper were studied. The X-ray diffraction test confirmed the formation of Cu2O on the anode as the dominant phase. Increasing the applied voltage changed the ratio of the produced Cu2O powders phases. The CSMM and the isolation of samples edges did not affect the type of the powder components or their ratio, but the applied voltage did. The CuO phase appeared only when the anode became outside the container. The shapes of the produced particles on the anode were cubic or irregular sphere depending on the applied conditions. Rather than in the solution, the growth of cubic forms took place on the anode itself. The particles formed on the cathode had the same shapes as those found in powders. When the CSMM was absent, the applied voltages had less influence on corrosion; but when edges were exposed, the effect was greater. The obtained results revealed increases in the corrosion activity at low pH values. [ABSTRACT FROM AUTHOR]

This study investigates the impact of incorporating TiC and TiB2 inoculants on the microstructure and corrosion performance of an arc-directed energy-deposited PH 13-8Mo martensitic stainless steel. The microstructural characterizations revealed partial dissolution of the incorporated ceramic-based nanoparticles, resulting in the formation of in situ TiC phase in the TiC-inoculated sample, while TiC and chromium-enriched M3B2 phases were formed in the TiB2-inoculated sample. Further investigations into the electrochemical response of the fabricated samples confirmed that the applied inoculation strategy slightly enhanced the corrosion resistance of the alloy, offering a valuable advantage for in-service performance for applications in harsher environments. The slight improvement in the corrosion resistance of the inoculated samples was found to be attributed to the formation of a higher fraction of low-angle grain boundaries and enhanced retained austenite content in the microstructure. However, it is essential to note that the formation of chromium-enriched M3B2 phases in the TiB2-inoculated sample led to a slight deterioration in its corrosion resistance compared to the TiC-inoculated counterpart. [ABSTRACT FROM AUTHOR]

[Objective] The deposition of Cl-containing harmful salts on the surface of service materials critically influences their corrosion process. The Qinshan Nuclear Power Station, located near the sea, has encountered corrosion issues due to the deposition of these harmful salts. Although researchers have conducted numerous in-depth studies on the corrosion behavior and mechanisms of materials in nuclear power plants, only limited literature addresses the deposition patterns of harmful salts on the surfaces of nuclear-grade materials. [Methods] A field environmental investigation was conducted to understand nuclear material corrosion in salty environments, and then a harmful salt solution for salt spray deposition experiments was formulated based on the investigation results following the ASTM standard. To investigate the deposition patterns of harmful salts on the surface of spent fuel storage canister materials, this solution was used for salt spray deposition on nuclear-grade materials. Tests were conducted at 90 °C to simulate the coastal service environment of the Qinshan Nuclear Power Station. [Results] The analysis of seawater composition revealed that the seawater near the Qinshan Nuclear Power Station is diluted by freshwater, as it is located near the Yangtze River estuary. Despite this dilution, a comparison with the global average sodium content of seawater indicated that the seawater near the Qinshan Nuclear Power Station retains the typical characteristics of normal seawater. The design results for the harmful salt solution indicated that, based on the total chloride content of substitute ocean water according to the ASTM D1141-98 standard (2021 edition), the concentration of each compound in the seawater near the Qinshan Nuclear Power Station must be multiplied by 4.075 26 for amplification. This adjustment allows the formulation of a harmful salt simulation solution for salt spray deposition that complies with ASTM standards. The experimental results of harmful salt deposition on the surface of nuclear-grade material at 90 °C indicated the following: By setting the sedimentation rate of the salt spray at 1.75 mL/(h·80 cm2) and establishing a single salt spray period as "1 min of salt spray followed by 15 min of standing," one salt spray period was necessary for the average harmful salt concentration on the surface of the sample to reach 0.1 g/m² (using thin slice samples measuring 100 mmx100 mmx 0.1 mm). To achieve a concentration of 1.0 g/m², 12 salt spray cycles were required (using flat samples measuring 50 mmx25 mmx2 mm). Finally, 112 salt spray cycles were needed to reach a concentration of 10.0 g/m² (also using flat samples measuring 50 mmx25 mmx2 mm). [Conclusions] The seawater near the Qinshan Nuclear Power Station retains the characteristics of normal seawater. This paper proposes a laboratory design concept and serves as a reference for evaluating the service life and performance of materials used in nuclear power plants operating in actual service environments. [ABSTRACT FROM AUTHOR]

This article investigates the challenges of maintaining the Machico Cable-Stayed Bridge in a marine environment, focusing on its implications for urban mobility. The primary problem addressed is the impact of harsh marine conditions on the structural integrity of the bridge, which poses significant challenges for ongoing maintenance and safety. The research highlights unique aspects such as the effects of saltwater exposure on materials and the interplay between infrastructure and urban transit dynamics. By emphasizing these critical issues, this study aims to provide insights into effective maintenance strategies and contribute to the broader discourse on urban mobility in coastal regions. [ABSTRACT FROM AUTHOR]

A reinforced earth wall is a structure in which reinforcement materials are placed in an embankment to build a vertical or nearly vertical wall surface. Such walls have been widely used in roads and in developed land since around 1960. Reinforcement materials have a set service life of 100 years and fall into two types: steel and geosynthetics. To ensure long-term durability, steel reinforcement materials are plated, while geosynthetics are designed with a limit strength designed to resist fracture for 100 years under the conditions of a given load placed on the reinforcement materials. However, owing to the difficulty of assessing the condition of reinforcement materials in soil, this paper proposes solutions based on non-destructive methods. Specifically, it proposes a method of assessing the amount of strain through an embedded optical fiber in the case of geosynthetic reinforcement materials, or magnetic surveying to investigate the degree of corrosion in the case of steel reinforcement materials. This paper demonstrates that it is possible to non-destructively assess the state of either type of reinforcement material. [ABSTRACT FROM AUTHOR]

Internet of Things (IoT) devices and small robots would benefit from higher-energy-density and disposable primary Al–air batteries, but corrosion and side reactions on the Al anode limit the widespread application of this chemistry. This paper studies how the physical and chemical characteristics of double-network hydrogel (DNH) electrolytes affect the anode oxidation, discharge morphology, and performance of Al–air batteries. The chemically crosslinked and physical–chemical crosslinked DNHs were made from biodegradable materials and showed enhanced corrosion inhibition compared to aqueous KOH solution, reducing the corrosion rate by 58% to 21 mmpy. An Al–air battery with a PVA-PAAM DNH extracted over 300 mAh cm−2 from Al at 10 mA cm−2. [ABSTRACT FROM AUTHOR]

The surface morphology influenced the corrosion resistance, which depended on the welding process and its parameters. In this study, we investigated the relevance of the welding process that produces excellent mechanical properties and corrosion resistance, which gives the best working performance for carbon steel pipes that transfer refined oil products in an Iraq oil refinery. AISI 1020-A106 carbon steel pipes are welded using shielded metal arc welding (SMAW) and gas tungsten arc welding (GTAW). Electrochemical corrosion tests were performed in 3.5% NaCl and immersion tests in heavy Naphtha at 50, 75, and 100 °C. The results show that retained austenite, ferrite, pearlite, and martensite phases are produced after the SMAW process. In contrast, ferrite, pearlite, and a small amount of martensite are produced after GTAW. The ultimate tensile strength of the SMAW samples was higher than those of the GTAW samples, but the GTAW samples had higher fracture elongation, and all samples had no cracks in the welding area during the bending test. The electrochemical and immersion corrosion rates of the samples welded with SMAW are higher than those welded with GTAW. The corrosion rate increases when the naphtha temperature increases and has a higher and unacceptable value at 100 °C. [ABSTRACT FROM AUTHOR]

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The economic cost of repairing corrosion-affected reinforced concrete structures (RCSs) means that reliable and accurate assessment and early detection methods must be sought after. Conventional techniques, such as visual inspections, or measuring either cover layer resistivity or the corrosion potential, are methods that require accessibility and involve personnel having to travel to take in situ measurements. Monitoring by embedded sensors is a much more efficient approach that allows early detection by remote sensing. This work presents the implementation of a new measurement protocol regarding the existing monitoring system called INESSCOM (Integrated Sensor Network for Smart Corrosion Monitoring). Along with the corrosion intensity measurement in embedded sensors, it also proposes monitoring the double layer capacity of the sensors' responses. It aims to determine, along with the rebars' corrosion rate, the triggering agent of the corrosion process. This study was carried out using three reinforced concrete scaled columns that were exposed to different environments. The results demonstrate with this new protocol that the remote INESSCOM monitoring system can establish the corrosion rate and identify the precursor agent of corrosion (carbonation or chlorides), even when the recorded corrosion rates are similar. [ABSTRACT FROM AUTHOR]

The development of Al-Ni alloys with a controlled microstructure has had a great impact on the field of study of aluminum-based alloys. In the present research, the influence of thermal parameters on the grain structures resulting from the directional solidification process of Al-Ni alloys with different alloy content has been studied. It has also been evaluated how different structures and the distribution of second phases influence the corrosion behavior and microhardness of alloys. The columnar-to-equiaxed transition (CET) was observed to occur when the temperature gradient in the melt decreased to values between 1.3 and 2.9 °C/cm. In addition, a small increase in the microhardness values was observed as a function of the Ni content. When the Ni content increases, the resistance to polarization decreases for samples with equiaxed grain structure throughout the range of compositions studied. Furthermore, the equiaxed grain structure presents higher resistance to polarization values than the columnar grain zone for alloys with a composition equal to or lower than the eutectic composition. [ABSTRACT FROM AUTHOR]

This study presents a novel framework for integrating corrosion effects into critical infrastructure seismic risk assessment, focusing on reinforced concrete (RC) structures. Unlike traditional seismic fragility curves, which often overlook time-dependent degradation such as corrosion, this methodology introduces an approach incorporating corrosion-induced degradation into seismic fragility curves. This framework combines time-dependent corrosion simulation with numerical modeling, using the finite–discrete element method (FDEM) to assess the reduction in structural capacity. These results are used to adjust the seismic fragility curves, capturing the increased vulnerability due to corrosion. A key novelty of this work is the development of a comprehensive risk assessment that merges the corrosion-adjusted fragility curves with seismic hazard data to estimate long-term seismic risk, introducing a cumulative risk ratio to quantify the total risk over the structure's lifecycle. This framework is demonstrated through a case study of a one-story RC moment frame building, evaluating its seismic risk under various corrosion scenarios and locations. The simulation results showed a good fit, with a 3% to 14% difference between the case study and simulations up to 75 years. This fitness highlights the model's accuracy in predicting structural degradation due to corrosion. Furthermore, the findings reveal a significant increase in seismic risk, particularly in moderate and intensive corrosion environments, by 59% and 100%, respectively. These insights emphasize the critical importance of incorporating corrosion effects into seismic risk assessments, offering a more accurate and effective strategy to enhance infrastructure resilience throughout its lifecycle. [ABSTRACT FROM AUTHOR]

Over recent years, the emergence of the offshore wind sector has spurred much interest in subsea cables. The predominant failure modes of subsea cables are associated with extreme environmental conditions. Wave-forcing during severe storms is less expected and causes more damage. A generalized multiphysics cable model is constructed to predict the movement, damage, and lifetime of subsea cables subject to dynamic wave and current action due to abrasion and corrosion. The present cable lifespan prediction model extended the previous tide-only model by considering the contribution of hydrodynamic forces by waves and the effect of wave and current incident angle relative to the cable. The predicted cable sliding distance at each section of the cable is combined with the Archard abrasion wear model and the corrosion model to predict the loss of cable protective layers and the resulting expected lifespan of the cable. The model is the first of its kind that can predict the spatial variation of wave and current loading, cable movement, damage, remaining lifetime, and cable failure modes and location. In addition, spatial and temporal variations of magnitude and direction of wave, current, and tide can be incorporated into the model for realistic large-scale simulations of cable performance in field conditions. The model compares well with previous laboratory experiments and numerical models. The present model was applied for the first time to the European Marine Energy Centre (EMEC)'s wave test site located at Billia Croo off the west coast of mainland Orkney, Scotland, and validated by the cable lifespan data. The 1-year and 100-year return period wave height and period and the average wave and tide conditions are used to drive the present cable lifespan model. It was found that the cable movement is predominantly driven by waves, and the previous tide-only model would predict zero cable movement, indicating the importance of the incorporation of wave contribution into the cable model. Furthermore, besides wave height and period, the wave angle relative to cable was found to be a determining factor for the cable movement and lifespan. The present multiphysics cable model provides a new capability to predict 70% of failure modes currently not monitored in situ and to deploy, plan, and manage subsea cables with improved fidelity, reduced cost, and human risk. [ABSTRACT FROM AUTHOR]

Aluminum alloy AlSi10Mg is a widely used engineering material that offers a very high strength‐to‐weight ratio and easy processing. It is common in the aerospace, medical, and automotive industries and has excellent machining and casting properties, as well as being easily made into fine powder. In recent years, it has become one of the most common light‐weight materials for additive manufacturing (AM). Its chemical composition and stability in powder form make it particularly ideal for laser powder bed fusion (LPBF) applications. It is one of the few available aluminum alloys that can be reliably processed using AM. Numerous studies have been dedicated to mechanical properties and design strategies, but much less attention has been given to corrosion behavior. This article reviews the corrosion behavior and the correlation between the microstructure and corrosion for AlSi10Mg when fabricated using an LPBF process. Specific topics reviewed include corrosion performance, corrosion issues (pores, surface roughness, and residual stresses), and passive film formation mechanisms and compare these to conventionally‐manufactured counterparts. In addition, this review discusses available methods for mitigating and avoiding corrosion in LPBF‐processed AlSi10Mg parts, including relevant post‐processing methods. [ABSTRACT FROM AUTHOR]

The influence of laser beam welding parameters (power, welding rate, focusing, head oscillation, shielding gas) on the microstructure, mechanical properties and corrosion resistance of the super-duplex stainless steel SAF 2507 was studied in this paper. The presented results clearly report the effects of welding parameter changes on the character of the steel's microstructure. The presence of secondary phase M2N in weld metals has an important influence on their mechanical properties. Optimal mechanical properties, an acceptable ferrite/austenite ratio, and the minimum content of M2N nitride required in the weld metal were acquired in the case the following application: 1100 W power, welding speed of 10 mm/s, focusing of 4 mm, and pure nitrogen shielding gas (20 L/min). [ABSTRACT FROM AUTHOR]

Chromium carbide powder agglomerated with nickel/chrome was deposited using a cold spray process onto a mild steel substrate. The deposits were heat-treated at 650 °C and 950 °C in ambient conditions to reduce porosity and improve adhesion between powder particles. The corrosion behaviour of these cold-sprayed materials was studied in artificial seawater conditions using electrochemical techniques. Heat treatment at 650 °C was found to best improve corrosion resistance, while the 950 °C treatment performed better than the as-sprayed condition but lower than the 650 °C sample. Microstructural analysis revealed complex phase transformations and structural refinements with increasing heat treatment temperature. The crystallite size of both Cr3C2 and NiCr phases decreased, while microstrain and dislocation density increased due to heat treatment. The formation of and subsequent reduction in Cr23C6 content indicated a complex sequence of carbide dissolution, transformation, and precipitation processes. The 650 °C heat-treated sample demonstrated superior corrosion resistance, evidenced by the highest corrosion potential, lowest passive current, and largest charge transfer resistance. This enhanced performance was attributed to the formation of a more stable and protective passive film, optimal carbide dissolution, and a homogeneous microstructure. Meanwhile, the 950 °C treatment led to excessive carbide dissolution and formed increased interfaces between the carbide and matrix. Mechanical property changes were also observed, with carbide hardness significantly decreasing after corrosion testing. These findings highlight the critical role of controlled heat treatment in optimising the performance of cold-sprayed Cr3C2-NiCr coatings, demonstrating that achieving superior corrosion resistance requires a delicate balance between microstructural refinement, phase transformations, and preservation of coating integrity. [ABSTRACT FROM AUTHOR]

Mg-based alloy anodes suffer from severe corrosion in alkaline electrolytes, which substantially impedes their cycle life and thereby limits their suitability as anode materials for nickel–metal hydride (Ni-MH) batteries. This work modifies the conventional 6 M KOH electrolyte by adding 0.1 M Al2(SO4)3·18H2O. The electrochemical hydrogen storage properties of Mg0.45Ti0.05Ni0.50 alloy in this electrolyte and its microstructural evolution during cycling are studied. In the 6 M KOH + 0.1 M Al2(SO4)3·18H2O electrolyte, a protective layer consisting of Mg2Al(OH)7 is formed on the surface of the Mg0.45Ti0.05Ni0.50 alloy anode during charge/discharge cycling instead of Mg(OH)2, effectively preventing further corrosion and improving its cycle life. The Mg0.45Ti0.05Ni0.50 alloy anode delivers a maximum discharge capacity of 479.0 mAh g−1 and maintains 318.4 mAh g−1 after 30 cycles in the 6 M KOH + 0.1 M Al2(SO4)3·18H2O electrolyte, which is significantly superior to that achieved in the 6 M KOH electrolyte (471.1 mAh g−1 and 201.8 mAh g−1, respectively). This work provides a new strategy for improving the cycle stability of Mg-based alloy anodes. [ABSTRACT FROM AUTHOR]

This study investigates the influence of pre-corrosion damage on the fatigue behavior of AlSi10MgMn high-pressure die-cast specimens, using the statistical distribution of corrosion depths. The analysis is conducted on two different surface conditions: an unmachined rough surface ( R a = 5.05 μ m ) and a machined, polished surface ( R a = 0.25 μ m ). For the unmachined specimens, the corrosive damage manifests as homogeneously spread localized corrosion, whereas the polished specimens exhibit less uniform but deeper corrosion. The average corrosion depth of the polished specimens is found to be slightly higher (313 μ m compared to 267 μ m ) with a broader depth distribution. Specimens are tested under a constant bending load amplitude in laboratory conditions at a stress ratio of R = 0 until fracture. A fracture mechanics-based methodology is developed to assess the remaining fatigue life of corroded specimens, utilizing short and long crack fracture mechanical parameters derived from SENB specimens. This model incorporates a thickness reduction of the critical specimen cross-section based on the corrosion depth distribution and combines it with a small initial crack of the intrinsic defect size ( a e f f = 14 μ m ). Regardless of the surface condition, using the most frequent corrosion depth for thickness reduction provides a good estimate of the long-life fatigue strength, while using the 90th percentile depth allows for a conservative assessment. [ABSTRACT FROM AUTHOR]