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Chloride ions are responsible for triggering severe corrosion in the marine environment. Hence, there is a need to deploy corrosion resistant materials such as hexagonal boron nitride (h-BN) sheet to protect mechanical components operating under such harsh conditions. In this work, a first-principles approach was employed to investigate the effect of fluorine modification on the thermodynamic and kinetic behaviors of oxygen on different kinds of vacancy-defective hexagonal boron nitride (h -BN) in a Cl-containing marine environment. Geometrical and electronic structures were systematically analyzed along with adsorption and diffusion behaviors. The existence of a low energy barrier implies that there is a relatively attenuated ability to inhibit O diffusion for double vacancy V BN - h -BN sheet compared to single vacancy V B - h -BN and V N - h -BN sheets. Interestingly, the fluorine functionalization for three defective h -BN sheet is found to cause an increased energy barrier of O diffusion. The F @ Cl @ V N - h -BN sheet possesses the highest diffusion energy barrier, indicating a superior anti-oxidation property in the marine environment. This study provides some fundamental guidelines for realizing high-performance h -BN sheets for protecting equipment and components used in marine applications. [ABSTRACT FROM AUTHOR]

The solvent method for CO2 capture has the advantages of mature technology and low cost, and is widely used. As commonly used absorbents, organic amines have the advantages of fast absorption rate and large absorption capacity. However, due to the chemical reaction between organic amines and CO2, the solution becomes corrosive, resulting in corrosion of equipment pipelines. The corrosion mechanism of organic amine solutions was reviewed. Hydrogenated amine ions, bicarbonate ions and water molecules are the main oxidants, which provide conditions for the occurrence of corrosion. The effects of the types and concentrations of organic amine solution, CO2 loadings, temperatures, O2 content and degradation products on the corrosiveness of the solution were discussed. Among them, CO2 loadings and temperatures are the main factors. The methods of using inorganic and organic corrosion inhibitors, adjusting the pH value of the solution and using stainless steel materials were summarized. The organic corrosion inhibitors for amine solutions are more worthy value of attention. The development direction of future corrosion inhibition technology was put forward. It is necessary to develop new corrosion inhibitors and combine them with corrosion resistant materials, which can provide a reference for further research and solving the corrosion problem of organic amine solutions. [ABSTRACT FROM AUTHOR]

Fiber-reinforced composite tubes offer numerous advantages over traditional metal tubes, including lower weight, higher strength and stiffness, corrosion resistance, and fatigue resistance. These tubes have the potential to act as energy absorbers, making it crucial to understand the factors influencing their energy-absorbing characteristics. This study focuses on experimentally investigating the crashworthiness of woven glass/epoxy composite tubes by analyzing the effects of the inner diameter and the extent of overlapping dropped-off plies. Circular cross-sectional tubes with different diameters (20, 25, and 30mm) and varying extents of ply overlap (0, ¼, ½, ¾, and 1 times the circumference) are subjected to impact loading and quasi-static compressive loading. The length-to-diameter ratio remains constant across all cases. The investigation examines the influence of the inner diameter and the extent of overlapping plies on parameters such as mean crushing force, energy absorption, specific energy absorption, crush force efficiency, and stroke efficiency, and compares the damage and failure mechanisms observed in different composite tube configurations. The results highlight that specimens with smaller diameters and a half overlap exhibit maximum crush load efficiency, contrary to specimens with larger diameters and full overlap. This study emphasizes the significance of considering the extent of overlapping and its geometry to tailor the energy absorption characteristics of composite tubes for specific applications. [ABSTRACT FROM AUTHOR]

β‐cyclodextrin/Graphene oxide@ quinoline Schiff base (β‐CD/GO@QS), a material of resistant to microbial corrosion, was successfully prepared. Surface morphology, structure and thermal stability were performed using scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and Fourier‐transform infrared spectra (FT‐IR). The mechanical properties and microbial corrosion resistance of 0.5 wt% β‐CD/GO@QS smart coating in simulated seawater were investigated by electrochemical analysis. The results indicated that GO could improve the integrity of coating and had the great dispersion which decreased the effective anodic area to Q235 steel dissolution. Additionally, the smart coating of β‐CD/GO@QS effectively formed protective film on the exposed Q235 steel surface in the scratch area which could prevent the occurrence of electrochemical reactions, resulting in the cathode reaction hardly happened. Through the SEM and EDS image, the 0.5 wt% β‐CD/GO@QS coating of the scratched area was not seriously corroded after 14 d in simulated seawater. [ABSTRACT FROM AUTHOR]

No doubt, the use of biomedical implants in the world has been of tremendous benefit to humans (animals as well), still gaining much relevance today, and commands greater prospects in the future. Developments in this field have been from the progression of the use of materials like wood, iron and gold as external limb support and indental applications, to more sophisticated materials today like biodegradable metal alloys, polymers, ceramics and composites materials capable of replacing damaged or worn‐out organs (eye, heart, lungs, liver, kidney, etc.), mimicking the bone, or for boosting other physiological features as in cosmetology. Appropriate applications of these implants in the human body still remain a challenge today due to several post‐surgical issues like cytotoxicity, thrombogenicity, allergenicity, carcinogenicity and inflammations all of which could be attributed to factors like biocompatibility, osseointegration, mechanical properties and corrosion resistance of these biomedical implants during service. The aspect of implants' corrosion is of much concern in the biomedical industry of which there have been several methods used to tackle it viz ‐use of corrosion resistant materials and inhibitors, metal plating, environmental and design considerations and protective coating techniques. This paper reviews five different surface coating techniques for preventing corrosion in biomedical implants, their descriptions and working principles. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a kind of super stable thermoset resin, phenolic epoxy vinyl ester resin (PEVER) is widely applied as a solvent and corrosion resistant material. However, its highly cross-linked three-dimensional network challenges its degradation and recycling. In this study, we report an efficient catalytic system of KOH/C2H5OH–H2O to degrade PEVER under a mild reaction condition of 160 °C. It is discovered that the efficiency of KOH for degrading PEVER resulted from the high affinity of K+ to PEVER. Besides the resin, K+ shows good affinity to other organic substances, such as ethyl acetate, toluene, and petroleum ether, and it surpassed largely Na+ (NaOH) in the affinity to organic substances. The NMR and FT-IR characterizations indicated the degradation of PEVER via the hydrolysis of ester bonds, by which high value-added copolymer of styrene and methacrylic acid (SMAA), potassium salt of SMAA (SMAA-K), and novolac glycidyl ether (NOGE) were obtained. SMAA-K can be used as an interface modifier owing to its surface activity. The modified filter paper prepared by SMAA has high hydrophobicity. NOGE can be recycled to prepare a new polyurethane material. This study provides a new strategy for the chemical degradation and recycling of thermoset PEVER waste. [ABSTRACT FROM AUTHOR]

To address the gap in material design strategies for structural components in molten salt-powered technologies, the current work aimed to identify key parameters governing corrosion induced degradation of materials during exposures in molten halide salts. The applicability of the data on dissolution rates of pure metals (e.g., Cr) in a given molten salt to enable predictions of corrosion behavior of multicomponent binary and ternary Fe-based model and Ni-based commercial alloys isothermally exposed in the purified KCl-Mg Cl 2 in quartz capsules at 700 and 800°C was evaluated. The influence of alloy chemistry on initial dissolution rates and the consequent impact on the time-dependent corrosion induced microstructural evolution in the alloy subsurface was predicted with a coupled thermodynamic-kinetic model. The model was well able to predict the Cr depletion in all investigated alloys demonstrating the ability of the proposed approach to enable a unique design strategy for structural materials in molten salts. [ABSTRACT FROM AUTHOR]

High temperature molten salt corrosion is of utmost importance for selecting and qualifying structural materials for critical applications. Pyrochemical reprocessing of spent metallic fuels of the future fast breeder reactors in India is widely considered. One of the main processes of pyrochemical reprocessing is electrorefining. Electrorefining is generally conducted in LiCl–KCl molten salt at 500–600 °C under an inert atmosphere. Research groups worldwide are involved in developing corrosion resistant materials and investigating the corrosion behaviour of various structural materials for LiCl–KCl applications under different environments. A wide variety of materials, including metals, alloys, intermetallics, single crystals, glass and ceramics, have been investigated in molten LiCl–KCl salt. This review focuses mainly on the corrosion assessment of materials for LiCl–KCl application; a complete literature review with emphasis on the corrosion issues of materials is provided. This paper reviews the corrosion issues of metals and alloys in molten salts and the selection criteria of corrosion-resistant materials for molten salts. Understanding the molten salt corrosion mechanisms and future research scope are also discussed. [ABSTRACT FROM AUTHOR]

Highlights: A full review article on the corrosion behaviour of additive manufacturing (AM) of metallic parts is presented with the aim of covering the significant lack of information on this subject. Corrosion resistance of light metallic systems and duplex stainless steels objects obtained by additive manufacturing (AM) processes is critically discussed, based on the synergism between variables linked with chemical composition, manufacturing processes, and service conditions. Methodologies for improving the corrosion resistance of metallic parts produced by additive manufacturing (AM) are highlighted. The available data allow us to state that potentiodynamic corrosion tests are the best methodology to characterize metal additive manufacturing (MAM) corrosion and this unique test should be selected for the evaluation of this phenomenon. There is a gap in knowledge and test procedure to properly identify the relationship between defects and corrosion behaviour of the most studied metal additive manufacturing (MAM) systems. Additive manufacturing is an important and promising process of manufacturing due to its increasing demand in all industrial sectors, with special relevance in those related to metallic components since it permits the lightening of structures, producing complex geometries with a minimum waste of material. There are different techniques involved in additive manufacturing that must be carefully selected according to the chemical composition of the material and the final requirements. There is a large amount of research devoted to the technical development and the mechanical properties of the final components; however, not much attention has been paid yet to the corrosion behaviour in different service conditions. The aim of this paper is to deeply analyze the interaction between the chemical composition of different metallic alloys, the additive manufacturing processing, and their corrosion behaviour, determining the effects of the main microstructural features and defects associated with these specific processes, such as grain size, segregation, and porosity, among others. The corrosion resistance of the most-used systems obtained by additive manufacturing (AM) such as aluminum alloys, titanium alloys, and duplex stainless steels is analyzed to provide knowledge that can be a platform to create new ideas for materials manufacturing. Some conclusions and future guidelines for establishing good practices related to corrosion tests are proposed. [ABSTRACT FROM AUTHOR]

33429946 9 Yeh C.-P., Tsai K.-C., Huang J.-Y. Influence of Chloride Concentration on Stress Corrosion Cracking and Crevice Corrosion of Austenitic Stainless Steel in Saline Environments. They performed a tensile test, low-temperature impact toughness, corrosion weight loss method, polarization curves, and electrochemical impedance spectroscopy on four bainitic steels with different niobium contents. They also investigated the corrosion behavior of the treated steel in aqueous borate buffer solution to correlate the corrosion behavior with the microstructure arising from the various heat treatments that were performed. [Extracted from the article]

This document is an editorial published in the journal Frontiers in Marine Science. It discusses the importance of understanding the characteristics and behavior of manmade materials in the marine environment in order to balance oceanic preservation and sustainable development. The editorial highlights several research topics related to marine science and materials surfaces, including the degradation of discharged polycyclic aromatic hydrocarbons using liquid phase plasma, the evaluation of wave effects on offshore structures, the grading of methane hydrate reserves, and the corrosion behavior of super austenitic stainless steel. The document also mentions a study on the selection of plastics suitable for oyster farming based on antifouling performance evaluation. [Extracted from the article]

Recently, solar-driven seawater desalination has received extensive attention since it can obtain considerable freshwater by accelerating water evaporation at the air–water interface through solar evaporators. However, the high air–water interface temperature can cause volatile organic compounds (VOCs) to enter condensed freshwater and result in water quality safety risk. In this work, an antioxidative solar evaporator, which was composed of MoS2 as the photothermal material, expandable polyethylene (EPE) foam as the insulation material, polytetrafluoroethylene (PTFE) plate as the corrosion resistant material, and fiberglass membrane (FB) as the seawater delivery material, was fabricated for the first time. The activated persulfate (PS) methods, including peroxymonosulfate (PMS) and peroxodisulfate (PDS), were applied to inhibit phenol from entering condensed freshwater during desalination. The distillation concentration ratio of phenol (RD) was reduced from 76.5% to 0% with the addition of sufficient PMS or PDS, which means that there was no phenol in condensed freshwater. It was found that the Cl− is the main factor in activating PMS, while for PDS, light, and heat are the dominant. Compared with PDS, PMS can make full utilization of the light, heat, Cl− at the evaporator's surface, resulting in more effective inhibition of the phenol from entering condensed freshwater. Finally, though phenol was efficiently removed by the addition of PMS or PDS, the problem of the formation of the halogenated distillation by-products in condensed freshwater should be given more attention in the future. [ABSTRACT FROM AUTHOR]

Conventional cements and plugs are challenged by corrosion in CO2-rich and extreme geothermal environments, due to the hostile chemistry and high temperatures. Thermite-based sealing and well intervention technologies are being applied in the oil and gas industry, combining the energy delivery capability of thermite materials with the sealing characteristics of low melt temperature alloys. The thermite reaction products (ceramics) and the sealing alloys used in these plugs both have very attractive corrosion properties, and their operating envelopes extend into geothermal conditions. Thermite plugs and platforms, without supplemental sealing materials, have been considered for nuclear waste isolation, carbon sequestration, and geothermal applications due to the geochemical stability of the ceramic product and its very high service temperature. This study addresses corrosion resistance of the thermite reaction products. A range of engineered thermite systems which yield thermite reaction products including pure aluminum oxide, feldspar, or aluminosilicate solid solutions (in addition to the iron produced in thermite reactions) was developed. These materials were evaluated for their strong acid resistance (pH 1), carbonate resistance (sodium carbonate) and thermal shock resistance (600 °C heating → cold water quenching repeated three times). Performance of different materials was evaluated based on the changes in mechanical properties, water-fillable porosity, phase changes under stress conditions. The aluminosilicate product exhibited very good corrosion resistance, both from material loss and strength perspectives, while the other products performed with varying degrees of stability. This paper presents the results of the thermite corrosion studies and describes the novel tools being deployed, and under development, to satisfy challenging barrier and intervention applications. [ABSTRACT FROM AUTHOR]

The aim of this work is the study of the argon implantation on the corrosion resistance behavior of AISI 304 stainless steel substrates. The effect of ion implantation dose on morphology and corrosion properties of AISI 304 SS has been investigated. In this work, argon ions of 30 keV energy have been implanted into AISI 304 stainless steel at different fluences ranging from 3 × 1017to 10 × 1017Ar/cm².The AFM analysis of implanted samples clearly shows significant change in surface. In order to evaluate the effect of the ion bombardment on the corrosion behavior, otentiodynamic tests were performed. The results show that the corrosion resistance of the samples strongly depends on the implantation fluences. The Corrosion potential and roughness curves obviously indicate that corrosion Potential variations caused by argon ion bombardment are inversely proportional to surface roughness. Corrosion current variations show an optimal dose at 5 × 1017ions/ cm² in which the corrosion resistivity is 12 times higher than unimplanted sample. [ABSTRACT FROM AUTHOR]

The growing need for more energy efficient systems has led to advent of hard and corrosion resistant materials which are difficult to machine with both conventional and non-conventional machining techniques. Although ECM offers athermal and force-free dissolution, the workpiece surface integrity in multicomponent materials is limited with ECM due to several multi-physical phenomena occurring on the surface like selective phase dissolution, passivation, pitting, particle breakout, etc. To tackle these challenges, aggressive acidic and basic reagents are added to the electrolytes. Although these reagents improve the machining performance, they are not sustainable for the environment and human life as they generate harmful waste which is difficult to dispose and recycle. Furthermore, the handling of these aggressive electrolytes requires specialized coatings, resins, filters, catalysts, etc. to protect the machine tools and equipment from damage. Hybrid laser-ECM (LECM) is a relatively novel drill-mill processing technique to process these advanced materials while using neutral electrolytes, thereby potentially reducing the negative impact of using acidic/basic reagents in electrolytes. Under controlled conditions and proper laser alignment, LECM can simultaneously apply laser and EC process energies in the same machining zone to provide synergistic benefits manifesting in terms of dominance of kinetics and thermodynamics over pure electrodynamics in ECM. This provides multi-fold benefits in improving passivation weakening and homogenize multiphase dissolution. Therefore, this study investigates for the first time the machining performance, removal behaviour, reaction products and power/resource consumption of LECM in neutral electrolyte in comparison to ECM in various neutral and basic electrolytes. The NbC–Ni cermet was used as the workpiece material, which is a cobalt-free alternative to conventional WC-Co. The results revealed that LECM in neutral NaNO 3 compared to ECM with NaOH addition not only provided better Sa (2.02 μm, 24% ↓), M.R.R. (153 μg/s, 31% ↑), aspect ratio (0.048, 14% ↑) and similar passivation weakening capability while maintaining a nearly neutral pH (8) of the reaction products, but also reduced electrolyte usage by 23.6% with a 16.4% increase in power consumption. These aspects make LECM a sustainable and cost-effective candidate for processing modern passivating multiphase materials like newer cermets, super alloys, high entropy alloys, etc. with nearly same performance as achieved by using ECM with acidic/basic electrolytes. Further fundamental and applied research is needed in LECM to meet the industrial specifications. [Display omitted] • LECM in neutral electrolyte provides sustainable, precise and productive machining comparable to ECM with aggressive electrolytes. • Machinability of NbC–Ni cermet is investigated as potential alternative to cermets with carcinogenic Co binder. • Material removal characteristics of NbC–Ni cermet with ECM/LECM are analysed. • Power and resource consumption, and environmental impact of LECM and ECM are reported. • LECM enhances processing benefits in sustainable way with marginal additional power consumption. [ABSTRACT FROM AUTHOR]

Nickel-titanium (NiTi) alloys are key in making medical implants due to their mechanical properties and biocompatibility, yet suffer from microbiologically influenced corrosion (MIC). This study isolated three samples of intestinal microbiotas from patient's stents to investigate their corrosion behavior on NiTi alloy. Using metagenomic analysis, corrosion electrochemistry, and morphology characterization, we found that different microbiota samples formed biofilms on NiTi alloy, causing varying degrees of pitting corrosion. The corrosion was linked to riboflavin-mediated MIC, with differences in riboflavin synthesis genes affecting corrosion rates. This research offers new insights into the MIC of NiTi alloys and helps develop more corrosion resistant materials. • Human intestinal microbiota significantly accelerates MIC of NiTi alloy. • Different human intestinal microbiota samples lead to distinct patterns of pitting corrosion and varying corrosion rates. • Riboflavin is identified as a facilitator of MIC by intestinal microbiota. [ABSTRACT FROM AUTHOR]

This section offers news briefs on the scientific and chemistry industry as of April 1, 2023. The High Court in Kenya has ordered to restrain Lords Healthcare from distributing and marketing five drugs in the country for infringing on property rights of Indian drug company Cipla. A report shows that medical and health sciences accounted for 402 million U.S. dollars or 221% of South African government expenditures on research and development (R&D) in 2021/2022.

The microstructure, corrosion resistance, and stress corrosion cracking behavior of an ascast and solid-solution Mg-1.8Zn-0.5Zr-1.5Gd biomagnesium alloy after extrusion deformation were studied. Results show that when the extrusion ratio was 7.7 and the extrusion temperatures were 350 and 360◦C, the as-cast and solid-solution alloys underwent complete dynamic recrystallization, and the grains were significantly refined. The precipitated phase in the extruded alloy is mainly composed of a nano-scale (Mg, Zn)3Gd and an Mg2Zn11 phase. A small amount of undissolved and broken micron-sized (Mg, Zn)3Gd phase particles appeared in the as-cast extruded alloy. The electrochemical corrosion produced during the stress corrosion process peeled off the (Mg, Zn)3Gd phase particles and induced rapid dissolution of the adjacent matrix. As a result, stresses were accumulated, and stress corrosion sensitivity occurred. At the same time, some larger-sized cracks appeared in the tensile fracture of the alloy. The difference in grain size and orientation in different regions of the solid-solution extruded alloy leads corrosion fracture to be composed of parallel grooves in different directions. Solution treatment of the magnesium alloy was found to reduce the stress corrosion susceptibility of extruded magnesium alloy and make it promising as a biodegradable implanting material. [ABSTRACT FROM AUTHOR]

The Na 2 O-WO 3 binary system is an important chemical system with various applications, such as catalysts, energy and corrosion resistant materials. In this study, phase equilibria and liquidus temperatures in the Na 2 O-WO 3 binary system have been experimentally determined in air. The system was investigated at the temperature range from 550 to 830 °C using a high-temperature equilibration and quenching technique. The microstructure and compositions of the phases obtained in the quenched samples were then analyzed by an electron probe micro-analyzer (EPMA). Binary compounds Na 2 W 2 O 7 , Na 2 W 4 O 13 and Na 2 W 6 O 19 have been identified and the liquidus temperature temperatures in these primary phase fields were determined. Two peritectic points in the system were confirmed and compared with previous data. The present study provided useful thermodynamic data including liquidus and solid solutions. Accurate phase equilibria data will be used as the base for the development of thermodynamic modelling. [ABSTRACT FROM AUTHOR]

Sapphire has the advantages of high hardness, high strength, strong corrosion resistance, etc. It has been widely used in many high-tech fields and is expected to become a new screen cover material for electronic products. However, the poor impact toughness of sapphire single crystal will limit its application in consumer electronics. Recently, the functional development, application, and toughening technology of sapphire has been widely studied. The review introduces the applications of sapphire in optics, semiconductors, laser materials, etc. Then, the research progress of sapphire strengthening and toughening by doping and particle injection are summarized, which can effectively improve the fracture strength and toughness of sapphire. Moreover, the future application of sapphire and work of sapphire strengthening and toughening are analyzed and discussed. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) can experience reverse current during start-up and shutdown due to local fuel starvation, which also lead to carbon corrosion in the gas diffusion layer (GDL) and significantly reduce the durability of PEMFCs. However, the degeneration of the gas diffusion backing (GDB) is currently unclear. In this work, variety rule of structural and physical parameters are taken as object to investigate the performance degradation of GDB under different carbon corrosion potential. The experimental results indicate that the electrical conductivity experience the most significant decrease in particular at the corrosion potential changes from 0.7 V to 1.4 V. The oxidation of GDB significantly reduces the output power density, leading to a 30.85% decrease in the maximum output power density compared to the uncorroded state. The simulation results suggest that the impact of porosity degradation is relatively insignificant, whereas the electrical conductivity is the most pronounced for the decrease in durability. The findings indicated that the primary determinant of temperature distribution is the heat generated by electrochemical reactions dependent on electrical conductivity. For future technology of corrosion resistance for the GDB, it is necessary to develop carbon corrosion resistant materials and control strategy. • High reverse potentials decrease the fuel cells output performance. • Electrical conductivity has the most critical impact on the durability. • Thermal conductivity degenerate has little effect on temperature distribution. • Electrical conductivity degenerate decrease the oxidation reduction reaction. [ABSTRACT FROM AUTHOR]

Surface and structural modifications of polycrystalline Tungsten were performed by using Nd: YAG laser (532 nm, 10 ns) at a fluence of 4.7 J/cm2 in the oxygen environment. The FESEM analysis of the central ablated region of the single-shot irradiated Tungsten revealed the formation of diffusive molten pools and channels due to incomplete melting of the material's surface. However, with 20 shots of laser irradiation, the surface exhibited cracks, diffusive melted channels and flowers-like structures which are attributed to exfoliation sputtering. On increasing the laser shots to 60, pores and nano-protrusions were observed. However, cones and organized ripples were formed at 80 shots which are attributed to the surface tension gradients effect. The structural characterization by XRD revealed a change in the preferred orientation of Tungsten from (110) to (200) and (211) planes after laser irradiation up to 60 shots. However, at 80 shots, the preferred orientation of the material was re-stored along (110) plane. The electrochemical testing of the Tungsten in Phosphate Buffer Saline (PBS) solution revealed a decrease in its corrosion rate by 80 % after a single shot of laser irradiation. The corrosion rate then marginally increased by increasing the laser shots to 40 and then decreased again upon further increasing the laser shots. The electrochemically tested surface of the untreated sample in the PBS solution exhibited deeper pits that were greatly reduced after the irradiation. The results of this study revealed that the laser irradiation can be potentially used to develop corrosion resistant materials. [ABSTRACT FROM AUTHOR]

It is important to check the economic losses due to spontaneous metallic corrosion of major infrastructures, precious equipment's, and ensure the sustainable growth. Fabrication of environmentally benign functional polymeric material by transforming agricultural waste and products into value added polymeric products is of great importance in recent times. Here, we report the formulation of functional hybrid polymeric material using corn oil (CO) as our starting material. The functionality of CO was improved by green route, to produce corn diol fatty amide (HECA). Functionalization of CO was achieved in systematic manner by following green chemistry approach. First, diol fatty amide (HECA) was prepared followed by conversion of terminal OH groups of HECA into acrylic ester using condensation reaction with acrylic acid (AA). The base polymeric moiety was further modified to include phenyl acetylene functionality and SiO2 nanoparticle entities. The formulation of hydrophobic stable polymeric structure is important to sustain highly corrosive environment and long‐lasting performance of the material. The inclusion of different functionality and hydrophobic groups were confirmed by Fourier‐transform infrared and proton nuclear magnetic resonance spectroscopies. The baked coating was finalized by addition of phenol formaldehyde polymeric resin in different phr (part per hundred part of resin). The transmission electron microscopy, scanning electron microscope, energy dispersive X‐ray spectroscopy, and elemental mapping of the coating material confirms the formation of a hybrid material with uniform distribution of inorganic and organic components. The potentiodynamic polarization and electrochemical impedance spectroscopic analysis verified the better resistive performance of inorganic hybrid over the counter organic coatings. The enhanced thermal stability, hydrophobic character, and corrosion resistance performance of CO based coating material indicates the potential of the synthesized green route materials. [ABSTRACT FROM AUTHOR]

Copyright of Steel Pipe is the property of Steel Pipe Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Vatten is the property of Foreningen Vatten and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the mechanical, automobile, aerospace, and construction industries, Ti and steel are the mostly commercial materials be used. But the poor hardness, wear, and corrosion resistance limit their applications. In this study, we presented a composite material that consists of thermal-sprayed titanium (Ti) layer on AISI 1020 steel. Then we added different concentrations of c-BN to the electrolyte in the MAO process to enhance the wear resistance and corrosion resistance. The operating parameters of MAO were set to 35A/dm2 current density, 450V voltage and 10 minutes operating time. The concentration of c-BN added to the electrolytes were 0.1 g L-1, 0.3 g L-1, 0.5 g L-1, 0.7 g L-1, 0.9 g L-1, and denoted as Ti/MAO-BN1, Ti/MAO-BN3, Ti/MAO-BN5, Ti/MAO-BN7, Ti/MAO-BN9, respectively. To determine the properties of the composite coating, measurements of coating thickness, surface roughness, microstructure, hardness, XRD analysis, EDS observations were performed. Then potentiodynamic polarization test and a ball-on-disc wear test were used to determine the corrosion resistance and wear resistance. All the results indicated that all Ti/MAO contained c-BN (Ti/MAO-BN) have higher hardness, lower surface roughness, and thicker coatings thickness than that of Ti/MAO-free (Ti/MAO-F). In the corrosion resistance, Ti/MAO-BN was at least about 64% better than Ti/MAO-F, with Ti/MAO-BN9 being about 5 times better. In the wear resistance, Ti/MAO-BN reduces the wear volume at least about 59% compared to Ti/MAO-F, with Ti/MAO-BN9 reducing the wear volume by about 70%. [ABSTRACT FROM AUTHOR]

Copper tubes are used in refrigerator and air conditioning unit heat exchangers. However, in some cases, the areas in copper tubes subjected to mechanical processing experience pitting corrosion. Therefore, a test scheme to rapidly evaluate the corrosion resistance of copper tubes in these sections and the effectiveness of the initial treatment on corrosion resistance were investigated. The initial treatment is a chemical treatment that improves the corrosion resistance of copper tubes. The corrosion of copper tubes was investigated by observing the surface after immersing the copper tube in various solutions containing hydrogen peroxide, chloride ions, sulfate ions, benzotriazole and hydrogen carbonate ions for one day. The test solution that contained a combination of 10 mg/L hydrogen peroxide (H2O2), 300mg/L chloride ions (Cl-), 300mg/L sulfate ions (SO42-) and 10 mg/L benzotriazole was found to replicate actual corrosion processes on the copper tubes over 1 day. The results indicated a high tendency for corrosion to occur in the mechanically processed sections. The improved corrosion resistance in these sections from the initial treatment was also confirmed in the test solution. Additionally, the corrosion resistance in the mechanically processed sections of copper tubes was weaker as the residual carbon amount increased. [ABSTRACT FROM AUTHOR]

• Mitigation of external and internal corrosion behaviour in high pressure high temperature (HPHT) oil wells based on material design and selection. • Main challenges associated with structural and stainless steels used in HPHT are sweet and sour corrosion. • Hydrogen ingress in HPHT results in embrittlement, stress induced corrosion cracking and corrosion fatigue leading to metal dissolution and final material breakdown in conventional dilute alloys. • Equiatomic and non-equiatomic complex concentrated alloys and coatings have better resistance to hydrogen embrittlement, stress corrosion cracking and corrosion fatigue than most conventional alloys in simulated HPHT environments. • Implications of potential applications of complex concentrated alloys such as cost and scalability issues are imminent. This review discusses potential applications of complex concentrated alloys (CCAs) for mitigating sweet and sour corrosion in high-pressure, high-temperature (HPHT) wells with concentrated chlorides, carbon dioxide and hydrogen sulphide. The harsh oil and gas environments lead to severe components failures through sour corrosion, sweet corrosion, hydrogen induced cracking, stress corrosion cracking and corrosion fatigue. Many of these failures are material driven. Hence the domain of complex concentrated alloys are being explored to reduce the severity of failures in the oil and gas industry, especially in HPHT zones. The CCAs possess high thermal stability, the balance of strength and ductility resulting from complex deformation mechanisms, and high creep resistance due to sluggish diffusion. These properties are driven by the design philosophy: high entropy and enthalpy of mixing, severe lattice distortion, sluggish diffusion, chemical ordering, and the cocktail effects. These effects allow for greater flexibility and many degrees of freedom which is absent in conventional one principal element-based materials. Most CCAs have shown excellent and superior mechanical and corrosion properties in some of the environments of currently used corrosion-resistant alloys in the oil and gas industry. This review highlights recent literature on potential high entropy alloy chemistries, microstructural features and their effects on mechanical and corrosion properties, and areas for future research directions. [ABSTRACT FROM AUTHOR]

Developing efficient microwave absorbing materials (MAMs) suitable for prolonged use in marine environments is of great importance. Laser cladding serves as one of the new techniques for the material of surface modification and microwave-absorbing materials in the 3D printing. However, it is usually challenging to prepare materials that combine desirable printability, corrosion resistance, and microwave absorption properties using this technology. To enhance the microwave absorption of laser-clad Ni-based alloys, the method of impedance modulation was employed by incorporating ceramic powders with varying AlN content. The results show that Ni/AlN/MWCNTs composite functional materials with core-shell heterostructures were prepared under optimized laser processing parameters. This unique core-shell structure optimizes impedance matching increased polarization loss and multiple scattering to boost microwave absorption. The optimized 20 wt% AlN content resulted in a minimum RL of − 13.24 dB at 13.86 GHz, in addition, electrochemical tests showed that AlN enhanced the resistance to the corrosion medium transfer during the corrosion process, and the corrosion resistance of the Ni/AlN/MWCNTs composites material (self-corrosion current density (8.52 × 10−8), the charge transfer resistance (1.55 × 10−5)). Therefore, this work provides innovative theoretical and practical insight for the design and manufacture of advanced microwave-absorbing materials for harsh environments by laser melting technology. [Display omitted] • The first application of laser cladding in the preparation of metal-based microwave-absorbing composite materials. • The coating design of the core-shell structure gives superior impedance matching and wave-absorbing capability. • Reveal the electromagnetic wave absorbing mechanism and corrosion resistance for the addition of AlN ceramics. • A new strategy for the regulation and the cladding of corrosion resistant wave-absorbing materials by in-situ deposition. [ABSTRACT FROM AUTHOR]

• Purpose of the current article is to describe casing and tubing pipelines' corrosion failures and their control. • CO 2 and H 2 S cause sweet and sour corrosion and enormously contribute to internal pipeline failure (≈ 60%). • The use of corrosion inhibitors is the most cost-effective way to prevent casing and tubing corrosion. • Mechanism of sweet and sour corrosion and formation of corrosion products depends upon various parameters. • The main input parameters are pH, temperature, P CO2 , P H2S , etc. Casing and tubing for oil and gas wells are frequently made of steel alloys. Many corrosive gases, organic acids, salts, and other contaminants are present in the fluids of oil and gas wells, which hurt their productivity, efficiency, and continuous production. The common corrosive species include carbon dioxide (CO 2), hydrogen sulfide (H 2 S), water (H 2 O), organic acids (HCOOH, CH 3 COOH etc.) and salts (NaCl, CaCl 2 , MgCl 2 , NH 4 Cl etc.) that can cause the corrosion of metals at any stage of production, purification, storage and transportation processes. The purpose of the current article is to cover the corrosion of oil and gas well casing and tubing and corrosion mitigation techniques. Numerous factors influence the corrosion rate in these wells, and various management techniques and procedures have been implemented to address corrosion-related problems in oil and gas wells. Corrosion-resistant materials are one of the most popular and frequently used techniques. To prevent internal pipeline corrosion, anti-corrosive and wear-resistance coatings are also utilized. Another frequent method against corrosion is using scavengers, primarily for H 2 S and O 2 , to lessen the corrosivity of the well fluids. The most popular H 2 S-scavenging technique uses alkaline solutions and activated carbon. Triazine and aldehydes are the most common and efficient non-generative H 2 S scavengers. The use of corrosion inhibitors is one of the most practical and cost-effective ways to prevent corrosion in well casing and tubing. The corrosion inhibitors adsorb at the point where corrosive fluids and internal pipelines interface, preventing the corrosive attack. [Display omitted] [ABSTRACT FROM AUTHOR]