Search

New-type magnesium alloy with prominent solubility and mechanical property lays foundation for preparing fracturing part in petroleum extraction. Herein, Mg-xZn-Zr-SiC alloy is prepared with casting strategy. Electrochemical and compression tests are conducted to assess the feasibility as decomposable material. Morphology, composition, phase and distribution are characterized to investigate decomposition mechanism. Results indicate that floccule, substrate component and reticulate secondary phase are formed on as-prepared surface. Sample also acts out enhanced compression strength to maintain pressure and guarantee stability in dissolution process. Furthermore, as decomposition time and zinc content increase, couple corrosion intensifies, resulting in gradually enhanced decomposition rate. Rapid sample decomposition is mainly due to basal anode dissolution, micro particle exfoliation and poor decomposition resistance of corroding product. Such work shows profound significance in preparing new-type accessible alloy to ensure rapid dissolution of fracturing part and guarantee stable compression strength in oil-gas reservoir exploitation.

Mg alloys are considered the most promising engineering materials because of their unique properties. However, the uncontrolled corrosion rate of these alloys limits their applications. Therefore, in this study, a micro-arc oxidation layer was used as a transition layer to “directly” grow a zinc-based metal-organic framework (MOF) composite coating on the surface of a Mg alloy (AZ91D). Herein, the two zeolitic imidazolate framework (ZIF-8) coatings with different morphologies were separately prepared by homologous metal oxide induction and a one-step in-situ growth method. The superhydrophobic composite coating showed strong hydrophobicity and self-cleaning properties, which could prevent the penetration of water and corrosive ions (Cl−) into the surface of AZ91D. Electrochemical tests demonstrated that the super-hydrophobic composite coatings greatly enhanced the corrosion resistance of AZ91D, and the corrosion current density decreased from 10−5 to 10−9 A/cm2. These results indicate that the ZIF-8 coatings are beneficial for improving the hydrophobicity and enhancing the corrosion resistance of Mg alloys. Therefore, MOF composite coatings provide a new strategy that can be used to prepare multifunctional anticorrosion coatings on metal substrates.

Formation of super-hydrophobic and corrosion-resistant coatings can provide significant corrosion protection to magnesium alloys. However, it remains a grand challenge to produce such coatings for magnesium-lithium alloys due to their high chemical reactivity. Herein, a one-step hydrothermal processing was developed using a stearic-acid-based precursor medium, which enables the hydrothermal conversion and the formation of low surface energy materials concurrently to produce the super-hydrophobic and corrosion-resistant coating. The multiscale microstructures with nanoscale stacks and microscale spheres on the surface, as well as the through-thickness stearates, lead to the super-hydrophobicity and excellent corrosion resistance of the obtained coating.

In-situ incorporation of layered double hydroxides (LDH) nanocontainers into plasma electrolytic oxidation (PEO) coatings on AZ91 Mg alloy has been achieved in the present study. Fumarate was selected as Mg corrosion inhibitor for exchange and intercalation into the nanocontainers, which were subsequently incorporated into the coating. It was found that the thickness and compactness of the coatings were increased in the presence of LDH nanocontainers. The corrosion protection performance of the blank PEO, LDH containing PEO and inhibitor loaded coatings was evaluated by means of polarization test and electrochemical impedance spectroscopy (EIS). The degradation process and corrosion resistance of PEO coating were found to be greatly affected by the loaded inhibitor and nanocontainers by means of ion-exchange when corrosion occurs, leading to enhanced and stable corrosion resistance of the substrate.

Electrochemical tests and surface analysis measurements were performed to study the corrosion behavior in a 0.9 wt.% NaCl solution at 37 °C of three NiTi shape memory alloys fabricated by laser-powder bed fusion (L-PBF). The passive film characteristics and corrosion resistance of L-PBF NiTi showed different features as a function of their preparation process settings. The passivation rate for L-PBF NiTi surfaces including defects, such as keyhole pores and cracks which showed high electrochemical activity accelerating the passivation reaction process, was higher in the early stages of immersion, but the corrosion resistance provided by such a rapidly formed passive film containing higher defect density is lower than that for an initially defect-free surface. The thickness of the passive film including a higher defect density does not necessarily relate to the corrosion resistance. The L-PBF NiTi prepared at a linear energy density of 0.2 J/m and volumetric energy density of 56 J/mm3 shows the least defects. Also, an outer Ti-rich and inner Ni-rich dense and corrosion protective passive film could be obtained for these L-PBF NiTi samples, which also results in a relatively low Ni ion release rate. A passive film model based on thickness, composition and defect density properties as a function of processing conditions is proposed to explain the difference in corrosion resistance of the various L-PBF NiTi.

The compatibility problems become main concern in the utilization of biodiesel especially regarding to degradation and corrosion. The present study is conducted to describe the corrosion behaviour that occurs in steel tanks after contact with palm-based biodiesel for a period of 7 months. The storage tank used is respectively made of galvanised steel (GS), carbon steel (CS) and stainless steel (SS). It is performed in vertical cylinders with a floating-roof model. In every 30 days of storage time, the profile changes in the wall, roof and base surface of each tank were observed. The oil fuel properties were monitored in the parameter of viscosity, acid numbers, water content and oil colour. The topographic profiles on the surface of the walls and bottom of each tank wetted by biodiesel were examined over three zones inside the tanks using an endoscope imager. The main results of this study indicate that the tank steel with different protective layers exhibits different types of corrosion. The corrosion was localized in SS tanks but generalized in GS and CS tanks. The oil contamination in SS tanks was relatively lower than that in CS and GS tanks. The type of corrosion performed differently in different zones on the inside of the tank. The potential for leaks is greater at the base than on the walls and roof of the storage tank.

Biodegradable magnesium (Mg) and its alloy show huge potential as temporary bone substitute due to the favorable biocompatibility and mechanical compatibility. However, one issue deserves attention is the too fast degradation. In this work, mesoporous bioglass (MBG) with high pore volume (0.59 cc/g) and huge specific surface area (110.78 m2/g) was synthesized using improved sol-gel method, and introduced into Mg-based composite via laser additive manufacturing. Immersion tests showed that the incorporated MBG served as powerful adsorption sites, which promoted the in-situ deposition of apatite by successively adsorbing Ca2+ and HPO42−. Such dense apatite film acted as an efficient protection layer and enhanced the corrosion resistance of Mg matrix, which was proved by the electrochemical impedance spectroscopy measurements. Thereby, Mg based composite showed a significantly decreased degradation rate of 0.31 mm/year. Furthermore, MBG also improved the mechanical properties as well as cell behavior. This work highlighted the advantages of MBG in the fabrication of Mg-based implant with enhanced overall performance for orthopedic application.

Recently, functional molecules such as Polydopamine (PDA), Hyaluronic Acid (HA) and heparin have been widely studied in the field of surface modification of magnesium (Mg) alloy stents for better degradation behavior and biocompatibility, but their further application is limited by undesirable anticoagulant function, uncontrollable degradation and easy bleeding, respectively. Regarding to this consideration, a magnesium Fluoride/Polydopamine/Sulphonated hyaluronic acid (MgF2/PDA/S-HA) composite coating was successfully prepared by applying S-HA with sulfur content of 9.71 wt% on the surface of ZE21B alloy in this study. The results showed that the composite coating with a unique mesh structure not only inherited the anticoagulant effect of sulfonic acid group and the excellent cyto-compatibility of S-HA with high sulfur content, but also significantly improved the corrosion performance of ZE21B alloy. These results indicate a great application potential of the composite coating in the field of cardiovascular biomaterials.

Morse taper junction tribocorrosion is recognized as an important failure mode in total hip arthroplasty. Although taper junctions are used in almost all shoulder arthroplasty systems currently available in the United States, with large variation in design, limited literature has described comparable analyses of taper damage in these implants. In this study, taper junction damage in retrieved reverse total shoulder arthroplasty (RTSA) implants was assessed and analyzed.Fifty-seven retrieved RTSAs with paired baseplate and glenosphere components with Morse taper junctions were identified via database query; 19 of these also included paired humeral stems and trays or spacers with taper junctions. Components were graded for standard damage modes and for fretting and corrosion with a modified Goldberg-Cusick classification system. Medical records and preoperative radiographs were reviewed. Comparative analyses were performed assessing the impact of various implant, radiographic, and patient factors on taper damage.Standard damage modes were commonly found at the evaluated trunnion junctions, with scratching and edge deformation damage on 76% and 46% of all components, respectively. Fretting and corrosion damage was also common, observed on 86% and 72% of baseplates, respectively, and 23% and 40% of glenospheres, respectively. Baseplates showed greater moderate to severe (grade ≥ 3) fretting (43%) and corrosion (27%) damage than matched glenospheres (fretting, 9%; corrosion, 13%). Humeral stems showed moderate to severe fretting and corrosion on 28% and 30% of implants, respectively; matched humeral trays or spacers showed both less fretting (14%) and less corrosion (17%). On subgroup analysis, large-tapered implants had significantly lower summed fretting and corrosion grades than small-tapered implants (P .001 for both) on glenospheres; paired baseplate corrosion grades were also significantly lower (P = .031) on large-tapered implants. Factorial analysis showed that bolt reinforcement of the taper junction was also associated with less fretting and corrosion damage on both baseplates and glenospheres. Summed fretting and corrosion grades on glenospheres with trunnions (male) were significantly greater than on glenospheres with bores (female) (P .001 for both).Damage to the taper junction is commonly found in retrieved RTSAs and can occur after only months of being implanted. In this study, tribocorrosion predominantly occurred on the taper surface of the baseplate (vs. glenosphere) and on the humeral stem (vs. tray or spacer), which may relate to the flexural rigidity difference between the titanium and cobalt-chrome components. Bolt reinforcement and the use of large-diameter trunnions led to less tribocorrosion of the taper junction. The findings of this study provide evidence for the improved design of RTSA prostheses to decrease tribocorrosion.

Light metals such as aluminum alloys which are being broadly used in automobile sideways, aerospace production as well as segments in military. A light-weight metals prominent for energy consume reduction, efficiency of gasoline and oil increment and superior security to environment. The main utilization of aluminum matrix alloy components have been manufactured by the appropriate behaviors of high tensile strength, hardness, decent machinability, great cast-ability and excessive resistance of corrosion. In the present investigation dealing with casting and heat treatment processes of aluminum alloys 6063 by two different methods such as Sand casting and Die casting. The characterization of AA6063 are analyzed with help of destructive and non-destructive techniques. Finally the results indicates that die casted material gives better results when it is heat treated than the sand casted material.

Additive manufacturing (AM) of Mg alloys has become a promising strategy for producing complex structures, but the corrosion performance of AM Mg components remains unexploited. In this study, wire and arc additive manufacturing (WAAM) was employed to produce single AZ31 layer. The results revealed that the WAAM AZ31 was characterized by significant grain refinement with non-textured crystallographic orientation, similar phase composition and stabilized corrosion performance comparing to the cast AZ31. These varied corrosion behaviors were principally ascribed to the size of grain, where cast AZ31 and WAAM AZ31 were featured by micro galvanic corrosion and intergranular corrosion, respectively.

The life span of a structure depends on the strength and durability of concrete. The use of mineral admixtures in concrete plays a major role in achieving higher strength and durability characteristics. At present nanotechnology is being used in the concrete to decrease the permeability of concrete and also to extend the life service. Nanomaterials are extremely small in size which when used in concrete, improves the strength and reduces porosity. This study gives the characteristics of concrete when Nanosilica (NS) and Multi-Walled Carbon Nanotubes (CNT) were added to it. Manufactured sand was used as a fine aggregate in replacement of natural river sand. For conventional and nano-concrete, the durability characteristics were assessed by conducting water absorption, sorptivity, accelerated corrosion, and carbonation tests after 28 days and 90 days of curing. The formation of hydration products was studied through microstructural analysis by SEM and XRD. Closely packed concrete was achieved with the addition of NS and CNT. The permeability and porosity were reduced for nano-concrete because of the filler effect of nanomaterials.

The corrosion inhibition behavior of Mg-8Li-3Al alloy in NaCl solution with sodium dodecyl sulfate (SDS) was investigated by hydrogen analysis, scanning electron microscopy (SEM), electrochemical test, scanning Kelvin probe force microscopy (SKPFM) and computational methods. Results showed that the corrosion resistance of Mg-8Li-3Al alloy in NaCl solution was effectively improved with SDS. The SEM and SKPFM results confirmed a dense, 200 nm-thick SDS-adsorbed layer had formed on the alloy surface. The separation energy ∆Egap and adsorption energy Eads of SDS on the Mg surface were calculated by density functional theory and molecular dynamics simulations, respectively. And the corrosion inhibition mechanism was hypothesized and described.

An AZ91–0.9Ca–0.6Y–0.5 MM (AZXWMM91100) alloy, which has higher corrosion resistance, ignition resistance, and extrudability than a commercial AZ91 alloy, has been developed recently. In this study, the AZXWMM91100 alloy is extruded at various temperatures (300–400 °C) and ram speeds (1–14.5 mm/s), and the cracking behaviors, microstructure, and tensile properties of the extruded materials are systematically analyzed. On the basis of the pressure limit and surface and internal cracking limit, the extrusion limit diagram providing a safe extrusion processing zone is established. All of the materials extruded at temperatures and speeds within the safe extrusion processing zone have high surface quality and moderate tensile ductility with an elongation higher than 10%. Moreover, they have a fully recrystallized grain structure and contain undissolved particle stringers arranged parallel to the extrusion direction. The grain size of the extruded material does not show any relationship with the Zener–Hollomon parameter (Z). However, the yield strength (YS) of the extruded material is inversely proportional to the logarithm of the Z value, and their relationship is expressed as YS = −31.2•log(Z) + 536. These findings may broaden the understanding of the AZXWMM91100 alloy with excellent chemical and physical properties and provide valuable information for the development of high-performance extruded Mg products using this alloy.

Carbon steel is the most widely used engineering material, and its corrosion is one of the main areas of concern in many industries. The most practical approach to control this problem is to use corrosion inhibitors. Currently, because of their good water solubility, excellent chemical stability, low cost and nontoxic features, carbon dots (CDs), especially heteroatom-doped CDs, have been developed as green corrosion inhibitors, but the corrosion inhibition efficiency and underlying mechanisms of single- or dual-element doping have not yet been accurately compared and analyzed. Inspired by this, eco-friendly nitrogen-doped and nitrogen, sulfur codoped CDs (N-CDs and N,S-CDs) are prepared via a one-step hydrothermal process, and a comparative study on their inhibition performance for carbon steel corrosion in strong acidic solution is performed. The results show that both N-CDs and N,S-CDs can restrain the corrosion of carbon steel, and their inhibition efficiency increases with increasing concentration and immersion time, reaching approximately 87.9% (N-CDs) and 96.4% (N,S-CDs) at 200 ppm after 1 h of immersion. Molecular dynamics simulation indicates that the strong interaction ability between N,S-CDs and the Fe substrate leads to higher corrosion inhibition performance than the single N doping case, benefiting from the multi-anchor adsorption of N,S-CDs on carbon steel in a strong acidic solution. Therefore, the facile preparation, eco-friendliness and high corrosion inhibition performance of N,S-CDs will provide a new approach for designing highly efficient carbon dots and broadening the application of carbon dots in the corrosion field.

The rapid degradation of magnesium (Mg)-based implants in physiological environment limits its clinical applications, and alloying treatment is an effective way to regulate the degradation rate of Mg-based materials. In the present study, three Mg alloys, including Mg-0.8Ca (denoted as ZQ), Mg-0.8Ca-5Zn-1.5Ag (denoted as ZQ71) and Mg-0.8Ca-5Zn-2.5Ag (denoted as ZQ63), were fabricated by alloying with calcium (Ca), zinc (Zn) and silver (Ag). The results obtained from electrochemical corrosion tests and in vitro degradation evaluation demonstrated that the three Mg alloys exhibited distinct corrosion resistance, and ZQ71 exhibited the lowest degradation rate in vitro among them. After addition of Zn and Ag, the antibacterial potential of Mg alloys was also enhanced. The in vitro cell experiments showed that all the three Mg alloys had good biocompatibility. After implantation in a rat femoral defect, ZQ71 showed significantly higher osteogenic activity and bone substitution rate than ZQ63 and ZQ, due to its higher corrosion resistance as well as the stimulatory effects of the released metallic ions. In addition, the average daily degradation rate of each Mg alloy in vivo was significantly higher than that in vitro, as could be due to the implantation site located in the highly vascularized trabecular region. Importantly, the correlations between the in vitro and in vivo degradation parameters of the Mg alloys were systematically analyzed to find out the potential predictors of the in vivo degradation performance of the materials. The current work not only evaluated the clinical potential of the three biodegradable Mg alloys as bone grafts but also provided a feasible approach for predicting the in vivo degradation behavior of biodegradable materials.

A mechanistic model has been applied for the prediction of corrosion rate in multiphase (water–oil-gas) flow regimes. This is due to inadequacies of existing models to adequately address a wide variety of corrosion dependent parameters with special emphasis on multiphase flow parameters. This model takes into account; water cut, volumetric phase fraction of oil and gas, temperature, pressure, other data collected relating to the pipe age, sand particle deposit, CO2 partial pressure, flow velocity, pH, chloride contents, mass transfer coefficients, and hydrogen sulfide. The applied model results show well above 91 percent prediction accuracy, while the prediction error ranges between 0.022 and 0.045 percent. When predicted results compared actual value (experimental data) with DeWaard and Milliams’ model; used in the oil and gas industries, it showed good agreement. It is seen that the resulting model produced an R2 value of 0.91 in comparison to 0.53, the value for Dewaard and Milliams’. It is obvious from numerical simulation that the multiphase flow parameters have major effects on the entire rate of corrosion of oil and gas multiphase flow pipelines. Finally, this research concluded by showing the developed model performance and comparison was made with numerical results. It is expected that the outcome of this research will be of significant help for the strengthening of the application of mechanistic models for predicting corrosion rate. This model will be useful for oil and gas industries worldwide for accurate prediction of corrosion rate.

Poly (L-lactic acid) (PLLA) based copolymers modified with δ-valerolactone (DVL) through random copolymerization (PVLA-R) and block copolymerization (PVLA-B) with various DVL content were prepared to investigate their degradation regulation and mechanism. Chemical structure, thermal properties, hydrophilicity, crystallization as well as the crystal defects of the obtained copolymers were respectively confirmed. Degradation regulation of both PVLA-R and PVLA-B, such molecular weight and pH value changes of PLLA based copolymers were investigated via vitro degradation method. In order to further explore the degradation principle of the two copolymers, their degradation residues at different stages were systematically studied. The addition and increasing content of DVL disturbs the regularity of original PLLA molecular structure, resulting in accelerating degradation of copolymers. Compared with amorphous region, the crystalline region of both two copolymers has better corrosion resistance, which could be confirmed by increased melting point and crystallinity of both PVLA-R and PVLA-B degradation residues. PVLA-B copolymers show relatively superior degradation resistance mainly due to their higher molecular weight, crystallinity and hydrophobic index than PVLA-R copolymers.

Revision total hip arthroplasty (THA) for adverse local tissue reactions (ALTRs) secondary to head-neck taper corrosion is associated with a high complication rate. Diagnosis of ALTR is based on risk stratification using the patient's history and examination, implant risk, serum metal ion levels, and imaging. The purpose of this study was to determine if stratification using similar risk factors is predictive of outcomes following revision THA for metal-on-polyethylene (MoP) ALTR.We performed a retrospective review on 141 patients revised for ALTR due to head-neck taper corrosion. Pain outcomes following surgery were analyzed using a generalized linear mixed model. Complications were defined as instability/dislocation, infection, fracture, nerve palsy, leg-length discrepancy, or reoperation.The overall complication rate was 17.7%. The odds of having pain decreased by 44% after revision surgery (Odds Ratio = 0.56, 95% Confidence Interval: 0.324 to 0.952). There was no significant difference in instability/dislocation based on either increased or decreased head-neck offset (P = .67) or magnetic resonance imaging findings of abductor loss, effusion size, and degree of ALTR (P = .73). Increased serum cobalt (P = .31) and chromium (P = .08) levels did not predict complications; however, a decreased cobalt-chromium ratio was associated with postoperative complications (2.8 versus 3.5; P = .002).These findings are the first to suggest that patients who have ALTR after MoP THA undergoing revision surgery demonstrated major pain relief. Increasing femoral head offset did not change rates of instability/dislocation. In clinical scenarios where preoperative cobalt-chromium femoral head offsets were greater than available ceramic head offsets, a mandatory decrease in femoral head offset did not increase rates of instability/dislocation.

In this study, Mg–6.0Zn–3.0Sn–0.5Mn (ZTM630) magnesium alloy was pre-activated by colloidal Ti, oxalic acid, and phosphoric acid, and a phosphate conversion coating (PCC) was prepared on the alloy surface. The morphology and corrosion resistance of the prepared PCCs were investigated. Surface morphology studies showed that the phosphate crystals that formed the coating were the smallest for the sample pre-activated by phosphoric acid. The coating on the colloidal Ti and the phosphoric acid samples had the largest and the smallest thickness and surface roughness, respectively. The reason for the discrepancy was analyzed by comparing the surface morphologies of alloy samples immediately after the pre-activation treatment and various phosphating treatments. X-ray diffraction analysis revealed that all three PCCs contained the same compounds. The corrosion resistance time from the copper sulfate drop test and the electrochemical data from the potentiodynamic polarization curves showed that the coating pre-activated by phosphoric acid had the best corrosion resistance. Finally, the 1500 h neutral salt spray corrosion test confirmed that the phosphating treated magnesium alloy, which was pre-activated by phosphoric acid, exhibited excellent corrosion resistance and behavior.

Superhydrophobic coating has been widely studied for its great applicational potential, such as for corrosion protection of magnesium alloys while it has been restrained by expensive materials, sophisticated preparation process and infirm rough structures. In this study, the electrochemical method was adopted by using a two-electrode system for rapid hydrophobic modification to obtain superhydrophobic kaolin. By mixing the modified superhydrophobic kaolin with commercial epoxy resin and polydimethylsiloxane glue, a paint can be formed and easily used on various substrates for preparation of superhydrophobic coating via spraying method. The influence factors on wettability of the modified kaolin and the mixing ratio of each component of the coating were explored. Also, the wettability, durability and anticorrosion of the prepared coating were evaluated comprehensively. The coating was able to maintain superhydrophobic after immersed in HCl solution at pH 1, the NaOH solution at pH 14, and 3.5 wt.% NaCl solution for 16, 21, 30 days, respectively. In addition, the coating exhibited 4A grade adhesion, high hydrophobicity after abraded for 200 cycles on a 600-mesh sandpaper with 100 g weight, and 99.86% anticorrosion efficiency after soaked in 3.5 wt.% NaCl solution for 20 days, demonstrating a good robustness and anti-corrosion property. Furthermore, the coating showed good transparency, flexibility and was easy to make in a large scale by the spraying method, which is of great significance to promote the practical application of superhydrophobic coatings and the anticorrosion Mg alloys.

The development of lignin-based anticorrosive epoxy coatings for steel protection is beneficial for both alleviating the fossil resource depletion and value-added utilization of lignin but remains a challenge due to the inherent heterogeneous structure of lignin. Here, we selectively extract the low molecular weight (MW) fraction of a crop residue-derived enzymatic hydrolysis lignin (EHL) through a bioethanol fractionation process and prepare epoxy resin by direct epoxidation of the bioethanol fractionated lignin (BFL). The coatings are then fabricated using 20-100 wt% of BFL-based epoxy resin (LEp) as the commercial epoxy resin substitute. The low MW and high p-hydroxyphenyl content of the BFL offer high solubility and good workability for BFL and LEp during epoxidation and coating production, respectively. Lignin-based coatings with 20-40 wt% LEp exhibit good adhesion property (5B) and superior corrosion resistance, compared to the commercial epoxy coating. Although coating with high LEp concentrations (i.e., 60-100 wt%) resulted in decreased adhesion strength, the coating with 100 wt% LEp still displayed corrosion protection performance comparable to that of the commercial epoxy coating. Overall, this study provides a simple and effective approach to converting lignin to epoxy resins for a wide variety of surface coating applications.

Corrosion behavior of AZ31 magnesium alloy in NH4+-bearing chloride solution with controlled pH was investigated by weight loss experiment, hydrogen collection, and electrochemical test combined with surface morphology and topography observation. The results show that NH4+ and pH of the solution can affect the corrosion of AZ31 magnesium alloy. The existence of NH4+ affects the formation and dissolution of corrosion products, which makes the protective effect of the corrosion product layer weaker. The change of pH value not only affects the corrosion mechanism of AZ31, but also alters the concentration of NH4+ ions in the solution, which further influences the corrosion product layer of AZ31, and finally makes the corrosion of AZ31 change significantly.

Objectives Magnesium alloys are the potential candidate for metallic implants due to their excellent mechanical characteristics, biodegradable nature, and properties similar to human bone. However, a high degradation rate is primary obstacle in implementing these alloys as biodegradable orthopedic implants. Powder-mixed electric discharge machining (PMEDM) is an emerging method of surface modification of metallic alloys that can be implemented to improve the corrosion resistance of Mg alloys. Therefore, PMEDM using zirconium (Zr) and manganese (Mn) powder particles has been proposed to modify the surface characteristics of Mg-4Zn alloy. Materials and Methods In the present work, Zr and Mn powders have been used in varying concentrations during PMEDM of Mg-4Zn alloy. Experiments were conducted as per mixed design L18 orthogonal array (OA). Taguchi and Grey Relational Analysis (GRA) have been used to optimize the process parameters. Analysis of response characteristics, namely material removal rate (MRR), surface roughness (SR), and thickness of the alloyed layer (TAL), has been carried out at different values of input variables (like powder additives (Pa), powder concentration (Cp), peak current (Ip), pulse on time (Ton) and duty cycle (DC)). The corrosion analysis was carried out by immersing the specimen (machined at an optimized setting) in simulated body fluid (SBF). Results It is observed from the analysis that Cp, Ip, and Ton play a pivotal role in evaluating response characteristics. The favorable setting suggested by the gray approach is Pa: Zr; Cp: 2 g/l; Ip: 4A; Ton: 50 μs; DC: 80%, while responses at this setting are confirmed by confirmation experiments with MRR: 32.14 mm3/min; SR: 5.578 μm and TAL: 8.28 μm. The immersion test signifies that the corrosion rate (CR) of PMEDMed sample (3.20 mm/year) is 40.74% lesser than the corrosion rate of polished sample (5.40 mm/year). Conclusion Zr powder shows better performance in terms of higher MRR, lower SR and higher TAL as compared to Mn powder during the PMEDM process. The corroded surface of polished sample exhibited larger size micro pits and cracks than the machined sample, which concluded that surface modification of MZ-4Zn alloy via PMEDM is a powerful tool to enhance its corrosion resistance.

Implant-associated infections (IAI) and osseointegration disorders are the most common complications in orthopedics. Studies have shown that neutrophils surrounding implants play a vital role in regulating these complications. Although magnesium (Mg) and its alloys are considered promising biodegradable bone implants, their role in neutrophil-mediated antibacteria has not yet been examined. Considering the rapid corrosion of Mg, it is necessary to develop methods to inhibit its corrosion. To solve these issues, a zinc-doped ferric oxyhydroxide nano-layer modified plasma electrolytic oxidation (PEO)-coated Mg alloy (PEO-FeZn) was developed in this study, and its antibacterial, immune anti-infective, and osteogenic ability were systematically evaluated. The results showed that PEO-FeZn nano-layer enhanced the corrosion resistance, biocompatibility, bactericidal activity, and osteoblastic differentiation activity of the Mg alloy. Moreover, PEO-FeZn nano-layer inhibited immune evasion-related gene expression and contributed to the formation of neutrophil extracellular traps (NETs) by activating the extracellular release of DNA fibers and granule proteins, and thereby suppressing bacterial invasion and promoting osseointegration in vivo in Staphylococcus aureus (S. aureus)-infected rat femurs. Overall, the findings of this study could serve as a reference for the fabrication of highly biocompatible and corrosion resistant Mg alloys to address the challenges of IAI and osseointegration disorders. STATEMENT OF SIGNIFICANCE: The widely used metallic biomaterials usually come with the risk of IAI. As the first responder around the biomaterials, neutrophils could form NETs to defense against microorganism and promote tissue remodeling. Therefore, biomaterials addressing antibacterial and neutrophils-modulatory strategies are highly necessary in reducing IAI. To solve these issues, we grew PEO-FeZn nano-layers in situ on Mg alloy using a simple and green technique. The nano-layer not only enhanced the corrosion resistance and biocompatibility of Mg alloy, but also elevated the antibacterial and osteogenesis capability. Moreover, nano-layer contributed to NETs formation, thereby suppressing bacterial invasion and even promoting osseointegration in S.aureus-infected femurs. Accordingly, this functionalized multilayer coating with antibacterial immunity represents a novel therapeutic strategy for IAI and weak osseointegration.

Novel hybrid coatings on pure magnesium were prepared by combining plasma electrolytic carburizing (PEC) with micro-arc oxidation (MAO) to further enhance the anti-corrosion property in this paper. Scanning electron microscopy (SEM) was used to observe the micro-structure of the coatings, meanwhile, energy dispersive spectrometry (EDS) and X-ray diffraction (XRD) were separately used to investigate the elemental as well as phase compositions of the coatings. The anti-corrosion property of the coatings was evaluated by potentiodynamic polarization curves as well as electrochemical impedance spectroscopy (EIS).The results show that PEC process is closely related with the effects of adsorption as well as diffusion of the activated carbon atoms, and it can provide a favorable pretreatment surface with predesigned chemical composition to obtain a new kind of phase, namely SiC with superior corrosion resistance and chemical stability, in the following PEC+MAO hybrid coatings. Meanwhile, PEC preprocessing also can afford an excellent micro-structure to increase the coating thickness as well as to improve the compactness of the PEC+MAO hybrid coatings. During the fabrication process of the PEC+MAO hybrid coatings, an overlapping phenomenon in regard to coating thickness can be observed instead of heaping up layer by layer. Compared with both single PEC surface modification layers as well as single MAO coatings, the PEC+MAO hybrid coatings exhibit more superior anti-corrosion property. Especially, the EIS data reveal that the PEC+MAO hybrid coatings can act as an effective protection system to provide relatively excellent long-range anti-corrosion protection. Note also that employing same MAO technique for both single MAO treatment as well as PEC+MAO combining procedure is the key to this research.

Hitherto, the myriad of researches conducted on biofuels coupled with their poor oxidative stabilities, show that none of these studies has considered monitoring the corrosive effects of Schinzochytrium sp. microalgae biodiesel on diesel engines. In this study, corrosion behaviors of mild steel (MS), aluminum (Al) and copper (Cu) were compared via immersion tests in preheated schinzochytrium sp. microalgae biodiesel and its blends at room temperature and 60 °C for 1200 h. Property-variation of the individual/blended fuels, corrosion rates/products of the metals, and their morphologies were examined. For the metals, the corrosion rates are in the order of Al

Zn metal anode is believed to be a promising anode material for aqueous Zn-ion batteries (ZIBs) due to the merits such as low electrochemical potential, low cost, high theoretical specific capacity, high hydrogen evolution overpotential, less-reactive property, environmental friendliness and easy processing. However, issues including uncontrollable growth of Zn dendrites, corrosion by aqueous electrolyte, large volume change and unstable interface hinder its further development. Recently, multifunctional metal-organic frameworks (MOFs) and their derivatives have shown huge advantages in solving the issues facing Zn metal anode, and large advances have been achieved. MOFs and their derivatives can stabilize Zn metal anode by interface engineering, designing host, decorating separator, constructing solid-state electrolyte and so on. Here we carefully summarize and analyse these advances. Meanwhile, some perspectives and outlooks are put forward. This review can promote the development of MOFs, Zn metal anode as well as aqueous ZIBs.

This article presents electrolytic deposition of thin Rare Earth (RE) coatings on Crofer 22 APU stainless steel substrates for high temperature applications, such as interconnects in solid oxide cell stacks. The deposition of coatings based on yttrium-, gadolinium-, lanthanum-, and cerium nitrates is discussed. The high temperature corrosion properties of surface-modified steels were examined using thermogravimetry and electrical resistivity measurements. Coatings and oxide microstructures were examined by XRD and SEM of surfaces and cross-sections. The results showed that the use of the RE element oxide layers reduced the growth of oxide scale, as evidenced by lower weight gain. The layers based on Y- and Gd-oxides showed the best corrosion protection properties. The electrical measurements showed that the surface-modified samples had lower resistance than the uncoated sample.

Epoxy resin powder coating has been successfully applied on the corrosion protection of magnesium lithium alloys. However, poor wear resistance and microcracks formed during the solidification have limited it extensive application. There are limited approaches to exploit such anti-corrosion and mechanical properties of magnesium lithium alloys. Herein, the epoxy resin powder coating with polydopamine modified molybdenum disulfide (MoS2@PDA-EP powder coating with 0, 0.1, 0.2, 0.5, 1.0 wt.% loading) was well prepared by melt extrusion to investigate its anticorrosion performance and wear resistance. The results revealed that the addition of MoS2@PDA enhanced the adhesion strength between coatings and alloys, wear resistance and corrosion protection of the powder coatings. Among them, the optimum was obtained by 0.2 wt.% MoS2@PDA-EP powder coating which could be attributed to well dispersion and efficient adhesion with coating matrix. To conclude, MoS2@PDA-EP powder coating is meaningfully beneficial for the anticorrosive and wear performance improvement of magnesium lithium alloys.

Low cost and high abundance rare earth elements Y and Ce have attracted tremendous interests of the industrial and scientific societies for fabricating the highly cost-performance efficient rare earth permanent magnets. However, the effect of separate replacement of Nd by Y or Ce on the performances of NdFeB-type magnet under the same atomic ratio and preparation conditions is still unclear. In this work, we systematically investigated the magnetic properties, thermal stabilities and service performances of (Nd0.8Y0.2)13.80FebalAl0.24Cu0.1B6.04 (at%, 20Y) and (Nd0.8Ce0.2)13.80FebalAl0.24Cu0.1B6.04 (at%, 20Ce) magnets. The results demonstrate that the μ0Mr, μ0Hc and (BH)max of 20Y magnet are respectively 1.325 T, 1.173 T and 343.467 kJ/m3, which are comprehensively higher than those of 20Ce magnet (μ0Mr = 1.310 T, μ0Hc = 0.948 T, (BH)max = 321.105 kJ/m3). Moreover, the 20Y magnet has higher thermal stability compared with 20Ce magnet which is favorable for the magnetic performances at elevated temperatures. The investigation of microstructure and elemental distribution indicates that the excellent magnetic performances of NdY-Fe-B magnet can be attributed not only to the preferable intrinsic properties 4πMs, Ha and Tc of Y2Fe14B, but also to the in-situ core-shell structure of the 2:14:1 matrix phase grain with Y-rich core and Nd-rich shell, along with the thicker grain boundary layer between the adjacent matrix phase grains in NdY-Fe-B magnet. Furthermore, the 20Y magnet exhibits better mechanical property and higher corrosion resistance than 20Ce magnet, which are helpful for prolonging the service life of the magnet in practical application.

This study systematically investigated the effect of equal channel angular pressing (ECAP) on the microstructure, mechanical, corrosion, nano-tribological properties and biocompatibility of a newly developed β Ti-28Nb-35.4Zr (hereafter denoted TNZ) alloy. Results indicated that ECAP of the β TNZ alloy refined its microstructure by forming ultrafine grains without causing stress-induced phase transformation, leading to formation of a single β phase. The ECAP-processed TNZ alloy exhibited a compressive yield strength of 960 MPa, and high plastic deformation capacity without fracturing under compression loads. Potentiodynamic polarization tests revealed the higher tendency of ECAP-processed TNZ alloys to form passive oxide films on its surface, which exhibited a lower corrosion rate (0.44±0.07 µm/y) in Hanks' balanced salt solution compared to its as-cast counterpart (0.71±0.10 µm/y). Nanotribological testing also revealed higher resistance of the ECAP-processed TNZ alloy to abrasion, wear and scratching, when compared to its as-cast counterpart. Cytocompatibility and cell adhesion assessments of the ECAP-processed TNZ alloys showed a high viability (111%) of human osteoblast-like SaOS2 cells after 7 d of culturing. Moreover, the ECAP-processed TNZ alloy promoted adhesion and spreading of SaOS2 cells, which exhibited growth and proliferation on alloy surfaces. In summary, significantly enhanced mechanical, corrosion, and biological properties of ECAP-processed TNZ alloy advocate its suitability for load-bearing implant applications. STATEMENT OF SIGNIFICANCE: Equal channel angular pressing (ECAP) provides a unique combination of enhanced mechanical and functional properties of materials by optimizing their microstructures and phase transformations. This study investigated the mechanical, nano-tribological, corrosion, and biocompatibility properties of a newly developed β Ti-28Nb-35.4Zr (TNZ) alloy processed via ECAP. Our findings indicated that ECAP of the β TNZ alloy refined its microstructure by forming ultrafine grains without causing stress-induced phase transformation. Compared to its as-cast counterpart, ECAP-processed TNZ exhibited significantly enhanced compressive yield strength, plastic deformation capacity, hardness, wear, and corrosion properties. Moreover, in vitro cytocompatibility and cell adhesion studies revealed high cellular viabilities, growth and proliferation of osteoblast-like SaOS2 cells on the ECAP-processed TNZ alloy.

Electrochemical splitting of seawater is highly preferable over freshwater electrolysis to produce sustainable hydrogen terrifically due to its abundance in nature. Seawater electrolysis is encouraging to produce green hydrogen and safe drinking water. The accomplishment of seawater electrolysis needs robust and cost-effective anode material that should acquire an excellent catalytic activity, durability, and selectivity for OER and have high resistance against Cl- corrosion. Here we report a free-standing anode consisting of partially amorphous sulfur substituted copper oxide (S-Cu2O-CuO) nanoneedles directly grow on Cu foil. Benefiting from high electrical conductivity, plentiful active sites, high intrinsic activity per active site, and fast rate for ionic and electronic transfer, these disorders nanoneedles structured S-Cu2O-CuO demonstrate outstanding OER performance needing an overpotential of 450 mV to attain a high geometric activity (1000 mA cm−2) in 1 M KOH. Its disordered surface structure and amorphous features lead to improved corrosion resistance and durability, making it a prospective anode for direct seawater electrolysis. It requires an overpotential of 420 mV to achieve a geometric activity of 500 mA cm−2 in alkaline seawater and sustain water electrolysis for 100 h without making hypochlorite. Because of the facile, scalable, and economical approach, the catalyst is highly promising for large-scale realistic alkaline seawater electrolysis.

In the preparation of plasma electrolytic oxidation (PEO) coating, the rapid heating of freely-happened electron avalanche under traditional discharge (TD) mode inevitably results in a strong eruption of electric breakdown melt. The PEO coating is loose and invariably composed of a very thin inner dense layer and an outer loose layer, as a result of which its properties and application have been limited greatly. In this work, for purpose of weakening the eruption of breakdown melt, thickening the inner dense layer, densifying the outer loose layer and improving the performance of PEO coating, ordinal discharge (OD) mode of PEO coating is developed by regulating the mass ratio of MgF2 to MgO (α) and voltage in the PEO investigation on AZ61 magnesium alloy in KF-KOH electrolyte. The formation mechanism under different discharge mode, electrochemical corrosion and wear of PEO coatings are investigated. The results show that the suitable α and voltage for effective OD are 1.3 and 130 V under which the freely-happened electron avalanche in MgF2 under TD mode can be restricted by the adequate adjacent MgO. Compared with TD mode, the inner dense layer, in which the ( 1 ¯ 0 1 ¯ ) plane of MgF2 is parallel to the (111) plane of MgO at their well-knit semi-coherent interface, is thickened to 2.4∼7.2 times, the corrosion potential (Ecorr) improvement is enlarged to 3.6∼13.2 times and the corrosion current intensity (Icorr) is reduced from 10.8∼9.499 to 0.433 (10−6 A/cm2). The outer loose layer is densified and the wear rate is lessened 65.5%∼89.8% by the evident melioration in surface porosity, impedance and hardness. This work deepens the understanding about the discharge of PEO coating and provides an available OD mode for preparing excellent PEO coating.

High efficiency, environmental protection and sustainability have become the main theme of the development of the protection engineering, requiring that the components not only meet the basic functions, but also have chemical properties such as acid and alkali corrosion resistance and aging resistance. Polyisocyanate-oxazodone (POZD) polymer has the above characteristics, it also has the advantages of strong toughness, high strength and high elongation. The concrete slab sprayed with POZD material has excellent anti-blast performance. In order to explore the damage characteristics of POZD sprayed concrete slabs under the action of contact explosion thoroughly, the contact explosion test of POZD concrete slabs with different charges were carried out. On the basis of experimental verification, numerical simulation were used to study the influence of the thickness of the POZD on the blast resistance of the concrete slab. According to the test and numerical simulation results that as the thickness of the coating increases, the anti-blast performance of the concrete slab gradually increases, and the TNT equivalent required for critical failure is larger. Based on the above analysis, empirical expressions on normalized crater diameter, the normalized spall diameter and normalized spall diameter are obtained.

The uncontrolled growth of lithium dendrites and accumulation of “dead lithium” upon cycling are among the main obstacles that hinder the widespread application of lithium metal anodes. Herein, an ionic liquid (IL) consisting of 1-methyl-1-propylpiperidinium cation (Pp13+) and bis(fluorosulfonyl)imide anion (FSI−), was chosen as the additive in propylene carbonate (PC)-based liquid electrolytes to circumvent the shortcoming of lithium metal anodes. The optimal 1% Pp13FSI acts as the role of electrostatic shielding, lithiophobic effect and participating in the formation of solid electrolyte interface (SEI) layer with enhanced properties. The in-situ optical microscopy records that the addition of IL can effectively inhibit the growth of lithium dendrites and the corrosion of lithium anode. This study delivers an effective modification to optimize electrolytes for stable lithium metal batteries.

The superlattice La-Y-Ni-based hydrogen storage alloys have high discharge capacity and are easy to prepare. However, there is still a gap in commercial applications because of the severe corrosion of the alloy in electrolyte and poor high-rate dischargeability (HRD). Therefore, (LaSmY)(NiMnAl)3.5 alloy was prepared by magnetic levitation induction melting, and then the alloy was coated with different contents (0.1 wt%–1.0 wt%) of nano-carbons by low-temperature sintering with sucrose as the carbon source in this work. The results show that the cyclic stability and HRD of the alloy first increase and then decrease with the increase of carbon contents. The kinetic results show that the electrocatalytic activity and conductivity of the alloy electrodes can be enhanced by carbon coating. The electrochemical properties of the alloy are the best when the carbon coating content is 0.3 wt%. Compared with the uncoated alloy, the maximum discharge capacity (Cmax) improves from 354.5 to 359.0 mAh/g, the capacity retention rate after 300 cycles (S300) enhances from 73.15% to 80.01%, and the HRD1200 of the alloy enhances from 74.39% to 74.39%.

One percent to 3% of contemporary non-cemented total hip arthroplasties (THAs) present with symptomatic mechanically assisted crevice corrosion (MACC). The incidence of this problem, however, as well as the rate of asymptomatic elevations in serum cobalt, is unknown.Cobalt and chromium levels were obtained in conjunction with radiographs at routine 10-year surveillance follow-up of THAs from a single manufacturer with a titanium stem, cobalt alloy femoral head, and cross-linked polyethylene countersurface.Ten-year follow-up of patients with 162 consecutive THAs revealed that 17 patients with 18 hips had died of unrelated causes prior to metal ion testing. Two hips were revised for other reasons, and of the remaining 142 hips, 33 were in patients who were lost, leaving 109 hips (77% of those in alive patients and unrevised for other reasons and 67% of the entire cohort) for investigation. Sixty-three patients (58%) had a serum cobalt less than 1 ppb, and 35 (32%) a cobalt of ≥1 ppb, a cutoff consistent with MACC. Of the 32 hips with definite MACC, 15 of 32 (47%) patients were symptomatic, 16 of 30 (53%) patients had adverse local tissue reaction on magnetic resonance imaging, and 19 of 32 (59%) patients have undergone revision surgery for MACC to date.At 10-year follow-up, a minimum of 22% (35/162) of hips had a cobalt level more than 1 ppb, consistent with MACC. Symptoms and adverse local tissue reactions are each present about one-half of the time, and 59% of those with documented MACC have undergone revision.

The consensus systematic risk stratification algorithm from the American Association of Hip and Knee Surgeons, the American Academy of Orthopaedic Surgeons, and The Hip Society summarizes clinical challenges in evaluation and treatment of metal-on-polyethylene total hip arthroplasty (THA) patients with adverse local tissue reaction (ALTR) due to mechanically assisted crevice corrosion (MACC), reviews up-to-date evidence, and identifies the areas for future research in order to provide a useful resource for orthopedic surgeons providing care to these patients. A painful THA has various intrinsic and extrinsic causes. ALTR is one of the intrinsic causes in patients with painful THA. The occurrence of ALTR due to MACC at modular junctions is likely to be multifactorial, including implant, surgical, and patient factors. Therefore, a systematic evaluation needs to involve a focused clinical history, detailed physical examination, laboratory tests, and imaging in order to identify potential differential diagnoses. There should be a low threshold to perform a systematic evaluation of patients with painful non-metal-on-metal THA, including patients with metal-on-polyethylene THA, and modular dual-mobility THA with the CoCr metal acetabular insert, as early recognition and diagnosis of ALTR due to MACC will facilitate initiation of appropriate treatment prior to significant adverse biological reactions. Specialized tests such as blood metal analysis and metal artifact reduction sequence magnetic resonance imaging are important modalities in evaluation and management of ALTR in patients with painful THA.

The development of green corrosion inhibitors is a challenging task as it has to comply with strict environmental regulations. Ionic liquids (ILs) have recently been proposed as promising corrosion inhibitors. The present paper reports on two ILs designed to act as green and efficient high-temperature corrosion inhibitors. The prepared ILs, namely, choline formate (ChF) and choline acetate (ChA), are composed of biologically active ions. To elucidate their structure and corrosion inhibition effect on mild steel in 5% HCl the ILs were subjected to characterization tests like proton nuclear magnetic resonance (

Al-based MIL-53 MOF nanostructure was synthesized hydrothermally and then co-deposited in the electroless nickel coating on AM60B magnesium alloy using Zr pretreatment as an eco-friendly underlayer. The MIL-53(Al) nanostructure was synthesized in the form of layered semi-cube crystals with the surface area and mean pore diameter of 985.72 m2g−1 and 2.00 nm, respectively. The SEM images captured with two various zooming scales from the surface of the plain and MOF containing electroless layers showed cauliflower-like morphology with even distribution of nodule size. Also, the sub-grains of the plain coating disappeared after incorporation of the MOF. Although, both the normal and nanostructure-containing electroless layers have crystalline-amorphous structure, but the nanocomposite coating showed less crystallinity. The average surface roughness of the plain electroless coating was about 309 nm, which decreased to about 222 nm after incorporation of the MOF. The XRD patterns showed that the characteristic peak of Ni broadened after incorporation of the MOF, probably due to the decreasing of the crystallinity. For the heat-treated normal and MOF containing coatings at 200 °C no phase transition takes place, but new peaks appeared for heat-treated coatings at 400 °C due to the crystallization and second-phase precipitation. The results of the EIS tests showed an increase in the amount of the charge transfer resistance (from 19 to 29 kΩ cm2) after addition of the MOF, which means an improvement in the corrosion resistance. Also, low Jcorr of the composite coating represents its higher corrosion resistance with respect to the plain coating. The micro-hardness values of the composite coating before and after the heat treatment were higher than the plain coating. Also, the Ni-P-MOF coating has a lower wear rate both before and after the heat treatment due to an improvement in its micro-hardness.

Fine grained ZN20 alloy was obtained by combining equal-channel angular pressing (ECAP) with extrusion. Microstructural observation showed an obvious grain refinement with an average grain size of 10 µm after ECAP. The original bimodal-grained structure composed of coarse grains with strong basal texture and fine grains with random texture was substituted by a new kind of bimodal-grained structure with finer grains and more random texture after 4 passes ECAP at 300 °C. The combination of grain refinement and texture weakening caused the ductility can be increased by 40% compared with the as-extruded alloy. Immersion test in simulated intestinal fluid revealed an improvement of corrosion resistance after ECAP. Grain refinement can stable the corrosion product layer and basal texture is more beneficial for the corrosion resistance than the non-basal texture.

Biodegradable magnesium alloys have excellent properties with respect to biodegradability, biocompatibility, and biomechanics, which may indicate a possibility of its application in intestinal stents. Investigation of Mg-Zn-Y-Nd alloy's application in intestinal stents has been performed. This study aims to investigate the degradation behavior of Mg-Zn-Y-Nd alloy intestinal stents coated with poly(L-lactide)/paclitaxel in the intestinal environment and its biocompatibility with intestinal tissue. In this paper, Mg-Zn-Y-Nd alloy's corrosion properties were evaluated by the immersion test in human feces, SEM and XRD, and animal tests. In vitro results showed that when the Mg-Zn-Y-Nd alloy was immersed in human feces for two weeks, its corrosion resistance could be improved by micro arc oxidation (MAO) and poly-l-lactide (PLLA) dual coating. Additionally, this result was also confirmed in vivo experiments by rabbit model. And animal tests also demonstrated that the Mg-Zn-Y-Nd alloy with MAO/PLLA/paclitaxel dual coating drug-eluting stents could inhibit the proliferation of local intestinal tissue around the stents. However, in vivo studies illustrated that the intestinal stents gradually degraded in rabbit model within 12 days. Considering the degradation rate of the stent was faster than expected in rabbits, the support performance of the scaffold requires further improvement.

Aqueous zinc energy storage devices, holding various merits such as high specific capacity and low costs, have attracted extensive attention in recent years. Nevertheless, Zn metal anodes still suffer from a short lifespan and low Coulombic efficiency due to corrosion and side reactions in aqueous electrolytes. In this paper, we construct an artificial Sn inorganic layer on Zn metal anode through a facile strategy of atoms exchange. The Sn layer suppresses Zn dendrite growth by facilitating homogeneous Zn plating and stripping during charge and discharge processes. Meanwhile, the Sn protective layer also serves as a physical barrier to decrease Zn corrosion and hydrogen generation. As a result, The Sn-coated anode (Sn|Zn) exhibits a low polarization voltage (∼34 mV at 0.5 mAh/cm2) after 800 testing hours and displays a smooth and an even surface without corrosion. Moreover, the zinc ion capacitor (Sn|Zn|| activated carbon) is assembled with an enhanced capacity of 42 mAh/g and a capacity retention of 95% after 10000 cycles at 5 A/g. This work demonstrates a feasible approach for the commercialization of aqueous Zn-based energy storage devices.

The slight-alkalization of generator internal cooling water (GICW) is widely used to inhibit the corrosion of hollow copper conductor and thereby ensure the safe operation of the generator. CO2 inleakage is increasingly identified as a potential security risk for GICW system. In this paper, the influence of CO2 inleakage on the slight-alkalization of GICW was theoretically discussed. Based on the equilibriums of the CO2-NaOH-H2O system, CO2 inleakage saturation was derived to quantify the amount of the dissolved CO2 in GICW. This parameter can be directly calculated with the measured conductivity and the [Na+] of GICW. The influence of CO2 inleakage on the slight-alkalization conditioning of GICW and the measurement of its water quality parameters were then analyzed. The more severe the inleakage, the narrower the water quality operation ranges of GICW, resulting in the more difficult the slight-alkalization conditioning of GICW. The temperature calibrations of the conductivity and the pH value of GICW show non-linear correlations with the amount of CO2 inleakage and the NaOH dosage. This study provides insights into the influence of CO2 inleakage on the slight-alkalization of GICW, which can serve as the theoretical basis for the actual slight-alkalization when CO2 inleakage occurs.

The development of innovative ceramic tiles looks for materials with improved mechanical and tribological properties as well as a higher corrosion resistance (high relative humidity, daily watering, household chemical cleaners). In addition, a greater durability leads to lower environmental impact. Along with their improved functionality and recyclability, ceramic tiles should also provide aesthetic properties. Ceramic tiles can be treated to modify the physico-chemical properties of the surface by metal coatings or metallic compounds, also providing an attractive metallic sheen appearance. In the present paper, titanium nitride (TiN) and zirconium nitride (ZrN) coatings were deposited on glazed porcelain stoneware by an industrial PVD multicathode arc deposition system under a reactive nitrogen atmosphere. After the process, the tiles showed a gold-like colour, a smooth surface and a coating thickness between 0.7 and 1.6 μm. The coating composition, scratch resistance and corrosion behaviour have been evaluated. It can be concluded that both coatings are suitable for use in domestic environments due to their stability and resistance to aggressive conditions. Few references have been found regarding these coatings on ceramic tiles for domestic and industrial applications, but it has been proved that they bring added value to traditional ceramics, giving new functional properties of ceramics both decorative and highly corrosion and mechanical resistance., This work has been partially funded by CENIT PROJECT 20072014, “Advances in technological coatings for decorative applications (ART-DECO)”, funded by CDTI.