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The document "Current Challenges in Corrosion Research" discusses the importance of understanding corrosion processes to maintain the integrity of critical components and installations. It emphasizes the need for sustainable strategies to prolong the service life of metallic structures, especially in industries facing demanding exposure conditions. The document presents ten articles focusing on topics such as laser shock peening effects on stress corrosion cracking, biofilm-induced corrosion inhibition, and the influence of thin films on corrosion resistance. The research contributions aim to advance developments in corrosion resistance and promote the creation of a sustainable society by addressing corrosion challenges in various industries. [Extracted from the article]

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]

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]

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]

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]

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]

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 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]

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]

Reinforced concrete multi-storey buildings undergo damages on a very large scale during an earthquake. It is indispensable to study the seismic behaviors of structure and make the structures safe. In recent time, studies have revealed that the use of GFRP material in building constructions. GFRP material is corrosion resistant, it has long term durability and high tensile strength, thus making its performance superior to that of steel material. Response Spectrum method is adopted for seismic evaluation of G+14 RC multi-storey building having steel rebar and GFRP rebar. The Modeling and Analysis is carried out in ETABS Ultimate 18.0.2 software. The steel rebar and GFRP rebar modeling is done for all three Soil Types in Seismic zone III as described in IS 1893 Part I: 2016. In this study the different models have been analyzed by using Response Spectrum function in Longitudinal and Transverse directions. The results of the analysis are acquired in terms of storey displacement, drift, shear, stiffness, modal acceleration, and modal time. From the current study it is seen that these results are fewer in GFRP rebar as compared to Steel rebar material. [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]

• 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]

The use of synthetic fibers as reinforcement in fiber-reinforced cementitious composites(FRCC) demonstrates a combination of better ductile response vis-à-vis metallic ones, enhanced durability in a high pH environment, and resistance to corrosion as well as self-healing capabilities.This study explores the effect of macro- and micro-scale polypropylene (PP) fibers on post-crack energy, ductility, and the self-healing potential of FRCC. Laboratory results indicate a significant change in fracture response, i.e., loss in ductility as curing time increases. PP fiber samples cured for2 days demonstrated ductile fracture behavior, controllable crack growth during tensile testing, post-cracking behavior, and a regain in strength owing to FRCC’s self-healing mechanism. Different mixes of FRCC suggest an economical mixing methodology, where the strong bond between the PP fibers and cementitious matrix plays a key role in improving the tensile strength of the mortar. Additionally,the micro PP fiber samples demonstrate resistance to micro-crack propagation, observed as an increase in peak load value and shape deformation during compression and tensile tests. Notably,low volume fraction of macro-scale PP fibers in FRCC revealed higher post-crack energy than the higher dosage of micro-scale PP fibers. Lastly, few samples with a crack of <0.5 mm exhibited a self-healing mechanism, and upon testing, the healed specimens illustrated higher strain values. [ABSTRACT FROM AUTHOR]

A compositionally complex alloy was designed, consisting of equiatomic concentrations of four low-cost commodity elements (Al, Fe, Mn, and Si). The alloy was characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The corrosion of the AlFeMnSi alloy, as evaluated using potentiodynamic polarization tests and electrochemical impedance spectroscopy in 0.6 M NaCl solution, was comparable with that of stainless steel (SS) 304L. Detailed X-ray photoelectron spectroscopy analysis was carried out, including the determination of high-resolution spectra and surface sputtering. In addition, scanning transmission electron microscopy was also used to study the surface film(s) developed after constant immersion. The AlFeMnSi alloy exhibited a unique form of 'passivity' that arises from the development of a silicon-rich surface film from dynamic incongruent dissolution. [ABSTRACT FROM AUTHOR]

Corrosion is an electrochemical phenomenon. It can occur via different modes of attack, each having its own mechanisms, and therefore there are multiple metrics for evaluating corrosion resistance. In corrosion resistant alloys (CRAs), the rate of localized corrosion can exceed that of uniform corrosion by orders of magnitude. Therefore, instead of uniform corrosion rate, more complex electrochemical parameters are required to capture the salient features of corrosion phenomena. Here, we collect a database with an emphasis on metrics related to localized corrosion. The six sections of the database include data on various metal alloys with measurements of (1) pitting potential, Epit, (2) repassivation potential, Erp, (3) crevice corrosion potential, Ecrev, (4) pitting temperature, Tpit, (5) crevice corrosion temperature, Tcrev, and (6) corrosion potential, Ecorr, corrosion current density, icorr, passivation current density, ipass, and corrosion rate. The experimental data were collected from 85 publications and include Al- and Fe-based alloys, high entropy alloys (HEAs), and a Ni-Cr-Mo ternary system. This dataset could be used in the design of highly corrosion resistant alloys. Measurement(s) pitting potential • repassivation potential • Crevice corrosion potential • pitting temperature • Crevice corrosion temperature • corrosion current density • passive current density • corrosion rate • corrosion potential Technology Type(s) digital curation Factor Type(s) alloy composition • temperature • pH • chloride ion concentration • alloy microstructure • alloy heat treatment Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.13611623 [ABSTRACT FROM AUTHOR]

Reinforcement of high strength, corrosion resistant materials to conventional ceramic composites effects on improvement of wear resistance, hardness and other mechanical behavior of the ceramics. In this paper it has been discussed about the effect of Titanium (Ti) metal powder (280 Mesh) is Reinforced with Commercially available Glass Ionomer Cement (GiC) to form a ceramic composites in the standard ratios of 8% and 16%. These composites samples were prepared in laboratory at room temperature and capsule dies were used for the preparation of the samples. All the samples were taken for wear, Scanning electron Microscope, Surface hardness, Diametrial tensile test, and Raman Spectroscopy. It is observed that the wear resistances of the Ceramic composites were improved in increasing the addition of Ti percentage, and greater hardness values were achieved on 8% of Ti addition to GiC ceramic composites. In SEM Images of the samples we have observed many cracks on the inner region because of setting time, from these, it is observed that settling time of these ceramic composites have greater role in the achievement of mechanic properties because, the inner region of the ceramic composites required more time to settle (Dry) when compared to the outer surface. [ABSTRACT FROM AUTHOR]

Bimetallic materials are construction materials that are increasingly used in many industries: in the graphic industry, tobacco processing industry for various cutting knives, in the chemical industry for various plants and vessels, food industry, military industry, etc. In the production of ships, their use becomes dominant, primarily as a combination of cheap construction materials highly resistant to corrosion, at a price closer to construction materials. The appearance of plating with the help of explosion energy has significantly increased the range and quality of available multilayer metals. Although stainless steels and aluminum are the most commonly used material for bimetallic and clad materials, materials such as titanium, zirconium or tantalum are increasingly used. The paper analyzes the process of explosion welding and the results of exploration of the explosion of a welded joint of copper and brass. The microhardness of the material in the welded joint, tribological characteristics and scratch test joint were analyzed. [ABSTRACT FROM AUTHOR]

Due to excellent biocompatibility and corrosion resistance, the application of titanium alloys in orthopedic and dental implants has been increasing since the 1970s. However, the elasticity of these alloys as measured by their Young's modulus is still about two to four times higher than that of human cortical bone. The most widely used titanium alloy for biomedical applications is Ti-6Al-4V, however, previous studies have shown that the vanadium used in this alloy causes allergic reactions in human tissue and aluminum, also used in the alloy, has been associated with neurological disorders. To solve this problem, new titanium alloys without the presence of these elements and with the addition of different elements, usually beta-stabilizers, are being developed. Manganese is a strong candidate as an alloying element for the development of new beta-type titanium alloys, due to its abundance and low cytotoxicity. In this study, Ti-10Mo-5Mn, Ti-15Mo-2.5Mn and Ti-15Mo-5Mn alloys were prepared in an arc furnace, which resulted in an alloy structure clearly showing the predominance of the beta phase with a body-centered cubic crystalline structure. The observed microstructure confirmed the results on the structural characterization of alloys. Measurement of the indirect cytotoxicity of the alloys showed that the extracts of the studied alloys are not cytotoxic for fibroblastic cells. [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]

Cr 2 O 3 is the best-known corrosion resistant refractory materials under high temperature extremely harsh environment. However, the formation of toxic, carcinogenic & water-soluble Cr(VI) compounds during its application remained a major predicament. Here, we have introduced a facile route to fabricate the Al 2 O 3 -CaO-Cr 2 O 3 refractory castables to mitigate Cr(VI) using basic silica sol (pH∼9) via in-situ secondary phase modification. Basic silica sols 0.25, 0.49 and 0.98 wt% (CaO/SiO 2 ratio of 5.8, 2.9 and 1.45 respectively) were doped by keeping the castables properties reasonable. Addition of silica drastically reduces the mid-temperature (500–1100 °C) formation of Cr(VI) phase (CaCrO 4), while relatively higher temperature Cr(VI) phase (hauyne, Ca 4 Al 6 CrO 16) totally disappeared from 900 to 1300 °C. However, at 1300–1500 °C, silica addition promote the solid solution phase formation like Ca(Al,Cr) 12 O 19 and (Al,Cr) 2 O 3 where chromium exists as +3 oxidation state. Also, silica addition reduces the dimensional tolerance of the castables at a higher temperature associated with the secondary phases (dehydration of cement phases and expansive formation of CaAl 12 O 19). A comparable mechanical strength (up to 156 MPa) and a remarkable Cr(VI) reduction (up to 94%) could be achieved upon silica addition. Image 1 • Al 2 O 3 -CaO-Cr 2 O 3 castables were fabricated via doping SiO 2 sol to mitigate Cr(VI). • CaCr6+O 4 reduces drastically on SiO 2 addition, while Ca 4 Al 6 Cr6+O 16 doesn't form. • SiO 2 promotes the formation of Ca(Al,Cr3+) 12 O 19 & (Al,Cr3+) 2 O 3 at 1300–1500 °C. • SiO 2 reduces dimensional tolerance of the castables at the higher temperature. • A remarkable mechanical strength (∼156 MPa) & Cr(VI) reduction (∼94%) was achieved. [ABSTRACT FROM AUTHOR]

Abstract Engineering structures are often subjected to the conditions of cyclic-loading, which onsets material fatigue, detrimentally affecting the service-life and damage tolerance of components and joints. Carbon fibre reinforced plastics (CFRP) are high-strength, low-weight composites that are gaining ubiquity in place of metals and glass fibre reinforced plastics (GFRP) not only due to their outstanding strength-to-weight properties, but also because carbon fibres are relatively inert to environmental degradation and thus show potential as corrosion resistant materials. The effects of cyclic loading on the fatigue of CFRP are detailed in several papers. As such, collating research on CFRP fatigue into a single document is a worthwhile exercise, as it will benefit the engineering-readership interested in designing fatigue resistant structures and components using CFRP. This review article aims to provide the most relevant and up-to-date information on the fatigue of CFRP. The review focuses in particular on defining fatigue and the mechanics of cyclically-loaded composites, elucidating the fatigue response and fatigue properties of CFRP in different forms, discussing the importance of environmental factors on the fatigue performance and service-life, and summarising the different approaches taken to modelling fatigue in CFRP. [ABSTRACT FROM AUTHOR]

This paper presents the experimental study of Austempered Ductile Iron (ADI) and high strength alloy steels, mainly 316 Austenitic Stainless Steel (ASS), an established corrosion resistant material. The success of this work will increase the available options of material selections for structural engineers for application in marine industries. The experiment was carried out with ASTM A536 grade ductile iron, which was produced using a high frequency dual track induction furnace of 2500kg, followed by subjecting the ductile iron samples to a specific parameter of heat treatment - Austenitizing (930oC for 140 minutes) and austempering (370oC for 10 minutes) in potassium nitrate salt bath to give ADI. Stress corrosion cracking (SCC) characteristics of the ADI and the standard 316 ASS specimens were evaluated in marine environment for 15 and 30 days respectively at constant strain rate of 5mm/min at room temperature. The stress-strain characteristics of exposed and unexposed specimens were compared and parameters such as yield stress, ultimate tensile strength, elongation and fracture strength were used as benchmark to assess SCC susceptibility. The study reveals that ductile iron properties (mechanical) were significantly improved after heat treatment, elongation increased by 27.04% and tensile strength by 58.62%. SCC test results show loss of elongation in the range of 23.20 - 26.48% for ADI in 15 and 30 days exposure. In contrast, 316 ASS retains most of its ductility. Both alloys retain their tensile strength in 15 days, however, there was decrease in the tensile strength of ADI by 5.93% as compared to 4.40% for 316 ASS in 30 days exposure. The fracture stress for ADI nevertheless occurred at 611.35MPa higher than 394.25MPa for 316 ASS. This indicates that ADI is significantly more resistant to SCC by providing better protection under overload condition in marine environment. [ABSTRACT FROM AUTHOR]

Abstract Surfaces of machine parts or tools are subjected to corrosive stresses or wear. To increase the wear resistance of surfaces, metal matrix composite (MMC) can be applied. For higher wear resistance, it is important to achieve a high particle content and a homogenous particle distribution. In this work, aluminium bronze substrate was reinforced by spherical fused tungsten carbides via laser melt injection. The laser power, travel speed and powder mass flow were varied. The influence of these process parameters on the hard particle content was investigated in single tracks. Furthermore, laser melting and laser melt injecting were compared. Laser melt injecting resulted in a significant increase in the track volume. Analytical calculation showed that the volume increase was higher than the volume of the injected particles. Single tracks composed of MMC could be produced without cracks and pores. Depending on the energy input per unit length, undesired melting of the particles was observed. The particle content was investigated via binary pictures from metallographic cross-sections using two different software packages. An approach to calculate the particle content as a function of the width, depth and height of laser melt injected tracks via circle segments is presented. [ABSTRACT FROM AUTHOR]

Abstract ZrO 2 films were prepared on 304 stainless steel by sol-gel method. The resistance of ZrO 2 films to high temperature and high humidity coal gas corrosion was studied. Experiments show that the film on the surface of the sample without vacuum treatment is ZrO 2 -Cr 2 O 3 -Fe 2 O 3 (ZrO 2 -passivation film) composite film. This film is effective against intergranular corrosion, however, as the corrosion humidity increases, sulfide corrosion occurs on the surface of the coated sample. The XPS test showed no change in the composition of the ZrO 2 film before and after etching. The sulfide of the sample is caused by Cr 2 O 3 -Fe 2 O 3. The high density ZrO 2 film is very resistant to high temperature coal-gas corrosion. Graphical abstract Image 1 Highlights • The stainless steel surface at the gap of the ZrO 2 film is passivated to form a ZrO 2 -Cr 2 O 3 -Fe 2 O 3 composite film. • The passivation film in ZrO 2 -Cr 2 O 3 -Fe 2 O 3 composite film provides a starting site for pitting corrosion. • ZrO 2 films was shown to provide good resistance to S penetration into the matrix at 600 °C. • Reducing the porosity of ZrO 2 film can improve its protective performance. [ABSTRACT FROM AUTHOR]

Abstract Ni-B/SiC micro- and nano-composite coatings were electrodeposited in a modified watts bath containing SiC micro- and nano-particles with the average size of 3 μm and 100 nm, respectively. The chemical composition, SiC content; X SiC (wt.%), morphology, surface roughness, thickness, hardness and corrosion resistance of the deposited coatings were studied as a function of the particle concentration in the deposition bath (C SiC = 2, 4, 6, 8 g/L) and deposition current density (i d = 0.5, 1, 2 and 3 A/dm2), using Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Inductively Coupled Plasma (ICP), X-Ray Diffraction (XRD), microhardness measurements and potentiodynamic polarization (PP) tastings, respectively. The results indicated that the SiC content and surface roughness (R a) of micro-composite coatings are increased with increasing both the C SiC and i d and reached to the maximum of X SiC = 14.8 wt% and R a = 4.58 μm at the C SiC = 8 g/L and i d = 3 A/dm2. While the SiC content and roughness of nano-composite coating are initially increased and then decreased with increasing both the C SiC and i d and the maximum of X SiC = 9.6 wt% and R a = 2.28 μm were obtained at the C SiC = 4 g/L and i d = 1 A/dm2. The thickness of both type of coatings increases almost linearly with i d and micro-composite coatings exhibit greater thickness values. The nano-composites exhibit higher hardness and corrosion resistance than micro-composites despite having lower SiC contents. The maximum hardness and minimum corrosion resistance were 1035 HV and 0.03 μA/cm2 for micro- and 889 HV and 0.38 μA/cm2 for nan-composite coatings, respectively. Highlights • Ni-B/SiC micro-/nano-composite coatings were electrodeposited using Watts bath. • SiC micro-/nano-particles improves Ni-B coatings hardness and corrosion resistance. • The highest hardness and corrosion resistance obtained at the maximum SiC content. • Nano-composite coatings show higher hardness & corrosion resistance than micro-ones. • SiC content of micro-composite coatings was higher than nano-composites coatings. [ABSTRACT FROM AUTHOR]

Highlights • A flexible, superhydrophobic and conductive nanofiber composite was prepared. • The nanofiber composite exhibited excellent durability and corrosion resistance. • The nanofiber composite could be used for wearable strain sensors. • The sensing performance could be maintained after cyclic abrasion and stretching. Abstract Conductive polymer composite based strain sensors have promising applications in the fields of artificial skin, wearable health-care device, etc. However, fabrication of strain sensors with good stretchability, anti-corrosion, excellent durability and reliability remains challenging. In this work, a superhydrophobic strain sensor based on conductive thermoplastic polyurethane/carbon nanotubes/polydimethylsiloxane (TPU/CNTs/PDMS) was prepared by ultrasonication induced CNTs decoration onto the electrospun TPU nanofiber surface, followed by the PDMS modification. Uniformly dispersed CNTs on the nanofiber surface with a hierarchical structure construct the conductive network. The PDMS layer with a low surface energy endows the nanofiber composite with superhydrophobicity thus anti-corrosion property. The introduction of CNTs/PDMS improves both the Young's modulus, tensile strength and the elongation at break. The superhydrophobicity and conductivity can be maintained after the cyclic stretching-releasing test, displaying excellent durability. When used as a wearable strain sensor, the nanofiber composite is capable of detecting body motion and could work even under harsh conditions (moisture, acid and alkaline environment), showing promising application in wearable electronics. [ABSTRACT FROM AUTHOR]

Abstract Magnesium (Mg) alloys are promising biodegradable metals for biomedical applications but limited by their too fast degradation rates. In this study, selective laser melting was used to fabricate three-dimensional honeycomb nanostructure-encapsulated Mg alloys, in which the honeycomb nanostructure was constructed by graphene oxide (GO) as a second phase and the grains of Mg alloys were encapsulated in the honeycomb unit. Results showed that GO distributed along the grain boundaries and gradually wrapped ɑ-Mg grains as GO content increasing. It was worth noting that a honeycomb nanostructure was formed with ɑ-Mg grains encapsulated in the honeycomb unit at a certain GO content (1.0 wt% in this study). As a result, the corrosion resistance and mechanical properties were both improved, which might be ascribed to the following mechanisms: (I) ɑ-Mg grains were refined due to the reduced connection and promoted nucleation by GO; (II) Benefiting from the outstanding anti-permeability of GO, the honeycomb nanostructure acted as a tight barrier to restrain the propagation of corrosion; (III) GO reinforced the corrosion layer to prevent it falling off the Mg matrix; (Ⅳ) The oxygen-containing groups on GO facilitated the deposition of bone-like apatite and further hindered the invasion of corrosive medium. These findings demonstrated the multiple defensive roles against corrosion in the honeycomb nanostructure-encapsulated Mg alloys and their great potential in biomedical applications. [ABSTRACT FROM AUTHOR]

Abstract Electroless Ni plating is commonly used as a coating of machined parts because of its superior corrosion resistance. The ITER Blanket Remote Handling System will use electroless Ni plating but will be operated in a γ-ray radiation environment, for which corrosion resistance—essential for the remote maintenance of ITER in-vessel components—has never before been demonstrated. This paper presents irradiation tests of electroless Ni plating carried out under dry or humid conditions. Corrosion resistance of electroless Ni plating was markedly affected in humid environments, however, in dry environments radiation resistance was verified. From surface analyses we can infer that radiolysis-enhanced corrosion was most likely caused by hydroxyl radicals produced from the interaction of water vapor and γ-rays in humid environments. [ABSTRACT FROM AUTHOR]

The corrosion behavior of Al-12Si-1Mg automotive alloy in absence and presence of zirconium traces is investigated in acidic, alkaline and salt media. The heat treated cast alloy specimens are allowed to stay in 0.5M H2SO4, 0.5M NaOH and 0.6M NaCl solutions for 47 days. The work is carried out using conventional gravimetric and electrical resistivity measurements as well as optical microscopy, SEM and EDX investigations. It is concluded that the alloys corrosion rate is greater in an acidic solution than in an alkaline one and that the anodization provides to decrease the corrosion rate of the alloys in all media. All alloys studied corrode less in a salt medium. The presence of Zr refines the grains and stabilizes the aluminium matrix phase up to 47 days of an exposure with no measurable effect on the alloys corrosion behavior. Formation of pores, a black corrosion product layer and a thin film of aluminum oxide and hydroxide on the surface is observed in the different media investigated. The microstructures obtained show that the process of alloys corrosion is localized at the area surrounding the precipitates of Al (Si, Mg) and Al-Mg which form hemispherical pits. The formation of crystallographic pitting is not found in a salt solution within the exposure times studied. [ABSTRACT FROM AUTHOR]

Abstract The Mg-4Ag and Mg-5Gd binary alloys' degradation and corrosion properties were studied under in-vitro conditions (in a SBF solution of pH 7.4 at 37 °C) by using various analytical techniques and time-frame windows (up to 3 vs. 28 days), and compared with the pure Mg alloy. Different kinetics and mechanisms of the alloys' degradation were identified, influencing their corrosion rates' dynamics. The Electrochemical Impedance Spectroscopy (EIS) measurements, being performed for up to 3 days, revealed that the corrosion of all three alloys are under a kinetic-controlled mechanism, among which only pure Mg and Mg-4Ag show a repassivation ability in this time-frame. However, the corrosion rates of binary alloys after 28 days of incubation reaching a value of around 0.33 mm/y and a release of 64 mg/L Mg2+ ions, that was accompanied by a pH change up to 8.3, an be lower compared to the pure Mg alloy (0.62 mm/y, 117 mg/L of Mg2+, pH of 9.0). While thick and homogenous layers of differently-shaped and chemically secondary-phased Mg(OH) 2 products were identified on both binary alloys, MgO products and an apatite structure are formed on the pure Mg alloy surface. The Mg-4Ag alloy seems to be biomedically the most appropriate regarding the in-vitro degradation process. Highlights • The corrosion of all Mg alloys follows kinetic-controlled mechanism. • Only pure Mg and Mg-4Ag show a repassivation ability during 3 days. • The corrosion rate of binary alloys in SBF after 28 days is 50% lower. • Thick & homogenous layers of differently-shaped Mg(OH) 2 are formed on binary alloys. • MgO products and an apatite structure are formed on pure Mg alloy surface. [ABSTRACT FROM AUTHOR]

Abstract In the present paper, we study the enhancement of the adhesion between the titania doped hydroxyapatite coating and the Ti6Al4V alloy substrate by the addition of three different biocompatible carbides. The coatings were prepared by the magnetron sputtering technique. The addition of interlayer preserved the crystalline structure of hydroxyapatite. The morphology of the coating is influenced by the interlayer composition. The adhesion of the coatings was significantly improved by the interlayer, independent of it's composition. The best adhesion was found for the coatings with NbC interlayer, which also showed the best corrosion resistance in simulated body fluid at 37 °C, due to its flat surface grown without any distinct features. As expected, the results of the in vitro biological tests were almost similar for all coatings comprising an adhesion layer, as the same titania doped hydroxyapatite layer was on top. The experimental results revealed that the adhesion between Ti6Al4V and titania doped hydroxyapatite was improved by a hard metal carbide interlayer, without affecting the required biomedical properties such as good corrosion resistance, high proliferation level of osteoblast cells, and good gene expression levels. [ABSTRACT FROM AUTHOR]

Abstract The amount of residual contact stress between an inner corrosion-resistant alloy pipe and its external carbon steel counterpart is the main challenge when manufacturing lined pipes. This study outlines the experimental and numerical evaluation of the manufacturing parameters of mechanically bonded double-walled pipes, produced by the thermo hydraulic shrink fit process. The measurements indicate that the gripping force between the outer 4-inch carbon steel and inner 3-inch stainless steel pipes was 33.94 MPa when processed at 350 °C with a hydraulic pressure of 30 MPa. The experimental results correlate with those of finite element method simulations for gripping force. The magnitudes of the measured gripping forces in the experiment are sufficiently high for most scenarios. The cross-sections of the final lined pipes were inspected for possible defects with the most common being the lamination-type defect for this production process. Highlights • Production Process of Double-Wall CRA Pipe by using the Thermo Hydraulic Shrink Fit (THSF) Process. • Experimentally and Numerically Investigating the Amount of Gripping Force. • Discussing the production Challenges and Possible Manufacturing Defects. • Comparison of the FEM Results With Theoretical Models in Literature. [ABSTRACT FROM AUTHOR]

Abstract Antithermal grain boundary migration is an interesting phenomenon that has been recently discovered. These grain boundaries behave opposite to what is expected of thermally activated grain boundary migration; the antithermal grain boundaries exhibit mobility that decreases with increasing temperature. Two recent studies have provided insight into important behaviors correlated with antithermal migration. O'Brien and Foiles (J Mater. Sci. Vol. 51, p. 6607–6623, 2016) demonstrated that the high mobility exhibited by an antithermal Σ7 grain boundary is enabled by ordered atomic motions. Ulomek and Mohles (Acta Mater. Vol. 103, p. 424–432, 2016) demonstrated that the thermal migration of a different Σ7 grain boundary exhibited a two-step migration process. In this work, we demonstrate that the antithermal temperature dependence exhibited by these types of grain boundaries is caused by a combination of these two discoveries. Specifically, ordered atomic motions about Coincidence Site Lattice atoms (atoms common to the lattices on either side of the grain boundary), seen by O'Brien and Foiles, are interrupted by additional thermal energy at higher temperature. This is the source of the two-step process seen by Ulomek and Mohles. This two-step process is akin to stick-slip behaviors observed in shear coupled grain boundary migration. As temperature is increased, the duration of the stagnant portion increases and the mobility decreases. This behavior is demonstrated through molecular dynamics simulations in nickel bicrystals over temperatures ranging from 100 to 1400 K for Σ7 and Σ9 grain boundaries. For these Σ7 and Σ9 grain boundaries, those that have ordered atomic mechanisms are almost exclusively antithermal, while those that do not have ordered atomic mechanisms are thermally activated. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract 304 stainless steel is widely used in many industrial fields, however, poor wear resistance of H 2 S limited its applications. In this study, novel composites coatings were deposited onto stainless steel surface by a liquid nitrocarburization technique. XRD, EMPA, SEM were conducted to investigate the surface modification of 304 Austenitic Stainless Steel after liquid nitrocarburization for 8 h at 703 K (430 °C). Wear test results showed that the wear resistance of nitrocarburized 304 stainless steel was increased in comparison with the non-nitrocarburized one. The corrosion potential was investigated by standard saturated hydrogen sulfide gas. And the results indicated that the austenite transformed into the S phase after forming supersaturated solid solution of N on the surface and kept intact after corrosion test. The corrosion current density was clearly reduced. Low diffusion coefficient of hydrogen atoms in S-phase reduced the possibility of environmental cracking of H 2 S and improved the H 2 S corrosion resistance of after liquid nitrocarburization. [ABSTRACT FROM AUTHOR]

Slippery liquid-infused porous surface (SLIPS) inspired by Nepenthes pitcher has attracted considerable attention owing to its great potential applications in icy or corrosive conditions. However, observing both anti-icing property and corrosion resistance of SLIPS has rarely reported before. In this paper, a simple approach was proposed to prepare SLIPS to protect metal from freezing rain and corrosion. The Al substrate was first electrochemically etched and anodized to construct hierarchical porous structures composed of AlOOH and Al2O3. After lowering the surface energy and infusing silicone oil, the SLIPS was obtained showing a water roll-off angle of 3°, which could exclude almost all liquids at an inclining angle of 5°. Comparative tests including freezing rain and corrosion in NaCl solution, were conducted on bare Al and prepared oil-infused slippery surface, demonstrating the excellent anti-icing and corrosion resistance properties of our SLIPS. Additionally, self-cleaning test was also successfully performed. So, this slippery Al surface with multiple outstanding properties would be useful for the anti-icing and corrosion resistance applications in extreme environment. [ABSTRACT FROM AUTHOR]

The thermal behavior, wettability, corrosion resistance, microhardness and interfacial reaction of quaternary Sn-0.7Cu-0.1Ni-xIn (x = 0, 0.5, 1.0 and 2.0 mass%) lead-free solder alloys were explored to reveal the effect of the indium (In) addition into the Sn-0.7Cu-0.1Ni solder on the properties of the solder alloy in the present investigation. The tested results revealed that the addition of small amount of In could lower both solidus and liquidus temperatures of the solder alloys. Moreover, the wettability of the solder alloy was remarkably improved by adding In element. The spreading area of Sn-0.7Cu-0.1Ni-1In was enhanced by 37% compared to that of Sn-0.7Cn-0.1Ni solder, meanwhile, the wetting angle of Sn-0.7Cu-0.1Ni solder was reduced by 39.1% with the addition of 2.0 wt% In. The intermetallic compound (IMC) formed between Sn-0.7Cu-0.1Ni-xIn solders and copper substrate was identified as (Cu,Ni)6Sn5 compound layer. The thickness and grains size of the IMC were slightly effected by the addition of In. The corrosion resistance of Sn-0.7Cu-0.1Ni-xIn solders increased with the addition of In, and the corrosion rate of Sn-0.7Cu-0.1Ni-1In solder was reduced by 62.8% compared with that of Sn-0.7Cu-0.1Ni solder in the 6% hydrochloric acid solution at ambient temperature for 14 days. Moreover, the hardness showed a decline of 14.7% when 2.0 wt% In was added into the Sn-Cu-Ni solder. [ABSTRACT FROM AUTHOR]

Abstract Fiber reinforced polymer (FRP) composites are commonly used in the chemical industry for storage tanks and pipelines, since most metallic alloys suffer from corrosion and result in costly maintenance and safety hazards. E-glass fiber is commonly used because of its low cost, but it is extremely susceptible to rapid degradation in low-pH environments. C-glass is an acid-resistant substitute, and while not as durable as carbon, it is much cheaper. Nevertheless, durable fibers are not the only key aspect of designing corrosion-resistant composites, as various degradation mechanisms must be considered. In this study, plain-weave laminates of C-glass and amine-cured epoxy are exposed to water and sulfuric acid solutions, and the relationship between diffusion kinetics and strength-loss is discussed. Results show that both solutions attack the fiber surface to some degree, but more importantly sulfuric acid increases the saturation uptake of water in the material, causing high swelling stresses that significantly reduce mechanical properties. [ABSTRACT FROM AUTHOR]

Carbon-based material is commonly used for anodes in MFCs, but its low conductivity often limits anodic performance. Application of corrosion-resistive current collector to carbon-based anode can be a promising strategy for increasing the anodic performance. In this study, it was hypothesized increasing metal current collector improved anodic performance. Two different carbon-felt anodes with titanium wires (CF-W) or stainless steel mesh (CF-M) as a current collector were tested in a single chamber MFC. In the short-term tests such as polarization and impedance tests, CF-M with the larger current collector area (21.7 cm 2 ) had 33% higher maximum power (2311 mW/m 2 ), 81% lower anodic resistance (3 Ω), and 92% lower anodic impedance (1.1 Ω). However, in the long-term tests, CF-W with the smaller current collector area (0.6 cm 2 ) showed higher performance in power and current generation, COD removal, and CE (51%, 10%, 11%, and 5% higher, respectively) and produced 41% higher net current in cyclic voltagramm (20.0 mA vs. 14.2 mA). This result shows that larger current collector is advantageous in short-term performance and disadvantageous in long-term performance, because the larger current collector is good for current collection, but interferes with mass transfer and microbial growth. [ABSTRACT FROM AUTHOR]

Abstract Additive manufacturing has emerged in recent years as one of the most in-demand technology for manufacturing of prototypes and components with complex geometries. Its application in biomedicine shows a big productive potential concerning customized implants with optimized geometries, reducing risks of rejection and achieving better ergonomic results. However, Ti-6Al-4V ELI pieces produced by Direct Metal Laser Sintering (DMLS) need a post heat treatment in order to reach optimum mechanical properties as well as to release internal stresses resulted from the manufacturing process. This study aims at analyzing the change of microstructure in DMLS samples by effect of heat treatments and its influence in the corrosion behavior and in the anodizing process. The surfaces were analyzed by 3D confocal profilometry, scanning electron microscopy and energy dispersive X-ray spectroscopy. DMLS samples showed different microstructures after heat treatments in the range from 650 to 1050 °C. The main difference in the microstructures is the nucleation and growth of β phase, which could have a detrimental effect on its corrosion behavior. The corrosion behavior was studied by cyclic potentiodynamic polarization in phosphate buffered saline solution at 37 °C. After anodizing, an oxide film was grown on the material surface, composed of a barrier and a nanoporous layer doped with F ions. The passive current density was reduced by approximately two orders of magnitude for all conditions, despite morphological differences on the layers. This is not only an improvement of the corrosion resistance but also a decrease in the ion release into bloodstream. Graphical abstract Image 1 Highlights • Microstructures containing β phase displayed pitting potential. • Microstructures affects the morphologies of the anodized oxide layers. • Despite morphological differences, anodizing was successful for all conditions. • Anodic layers reduced current density by two orders of magnitude for all conditions. [ABSTRACT FROM AUTHOR]

This research work is focused on examining the turning behavior of Incoloy 800H superalloy by varying important cutting parameters. Incoloy 800H is an Iron- Nickel-Chromium based superalloy; it can withstand high temperature (810°C), high oxidization and corrosion resistance. But, it is difficult to turn in conventional machines and hence the present work was carried out and investigated. Experiments were conducted based on the standard L27 orthogonal array using uncoated tungsten inserts. The cutting force components, namely, feed force (Fx), thrust force (Fy) and cutting force (Fz); surface roughness (Ra) and specific cutting pressure (SCPR) were measured as responses and optimized using Taguchi-Grey approach. The main effects plots and analysis of mean (ANOM) were performed to check the effect of turning parameters and their significance on responses of cutting forces in all the direction (FX, FY, FZ), the surface roughness (Ra) and specific cutting pressure (SCPR). The tool wear and machined surfaces were also investigated using white light interferometer and SEM. [ABSTRACT FROM AUTHOR]