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We investigate the glassy-state properties of Mg2Ca, Al2Ca, and Al4Ca from the grafting application viewpoint. We employed classical molecular dynamics to examine the phase transition, structural, thermodynamic, transport, and mechanical properties in the amorphous state. All properties suggest successful simulations of the glass phase at and below the glass transition temperature, ranging between 550 and 689 K for Mg2Ca, Al2Ca, and Al4Ca. Computed results are compared and discussed with the reported findings and known mechanical and thermal properties of the various parts of the human bones and biocomposites. The comparison establishes that the mechanical, thermal, and transport properties significantly improve in the glass phase compared to its crystalline alloy form. At 300 K, studied glasses have densities in close agreement with human bone density. Structural analysis and heat capacity show the second-order phase transition, verifying the formation of the glass structure. The targeted glasses exhibit excellent thermal conductivity and thermal diffusivity compared to other commonly used biocomposites for bone grafting. Furthermore, the simulated elastic properties, viz., the Poisson ratio, G/B ratio, Cauchy's pressure, and yield strength, are in close agreement with the mechanical properties of various parts of human bone. The predicted ductility nature, contrary to the brittle character of Mg2Ca, Al2Ca, and Al4Ca crystalline alloys, proves the superiority of the glassy form for the implant's functioning. The minimum enthalpy of formation and thermodynamic stability of studied compounds benefit the synthesis process; hence, we propose that the studied glasses are persuasive materials for experimental synthesis aimed at bone grating applications. [ABSTRACT FROM AUTHOR]

Excessive cooling of air is required in conventional air conditioning systems to reduce the humidity, leading to the development of desiccant wheel-based air conditioning systems. The desiccant wheel consists of desiccant material which is deposited on matrix material. In this study, aluminum, magnesium alloy, Teflon, and fiberglass have been considered matrix materials of the desiccant wheel. A one-dimensional mathematical model has been developed to evaluate the effect of these matrix materials. The results show that fiberglass can be selected as a suitable matrix material for drying applications because it has maximum moisture removal (MR; 1.92 g/kg) and temperature difference (4.72 °C) at optimal rotational speed, which are desirable for drying. While aluminum can be selected as a suitable matrix material for air conditioning applications because, at the optimal rotational speed, it has lower maximum MR (1.26 g/kg) and temperature difference (3.14 °C) as compared to other matrix materials. As moderate maximum MR and lower temperature difference are the requirements for air conditioning. A similar trend of results has been also obtained for other parameters (volume ratio, regeneration velocity, regeneration temperature, etc.) of this study. [ABSTRACT FROM AUTHOR]

Europium-hydroxyapatite (Eu-HA) nanocomposite was developed via continuous hydrothermal synthesis. Eu+3 ions partially replaced the Ca+2 ions within hydroxyapatite molecular structure. High quality Eu-HA nanorods of 20 nm width and 6 μm lengths were verified via TEM micrographs. Eu-HA maintained the crystalline structure of HA with minimum change; material studio software confirmed the partial replacement of Ca+2 by Eu+3. XPS analysis demonstrated Eu+3 content of 6.91 atom %. Ca/P ratio was found to be 1.405 and 0.118 for virgin HA and Eu-HA respectively; this was ascribed to the partial replacement of Ca+2 with Eu +3. The EDAX mapping verified the uniform dispersion of Eu ions within Eu-HA structure. Eu-HA nanocomposite was uniformly distributed in silica sol-gel matrix; subsequently it was applied on AZ31 magnesium alloy. The corrosion performance of Eu-HA sol-gel coating nanocomposite (Eu–S) was evaluated using different electrochemical techniques including Potentiodynamic Polarization (PDP), Electrochemical Impedance Spectroscope (EIS), and Electrochemical Noise (EN) in aerated 0.1 M NaCl solution. Corrosion protection was assessed to that of neat silica sol-gel coating (NSG). Pitting was detected over the whole NSG coated sample, after few hours of immersion in the corrosive solution. EuS coated AZ31 withstand up to 144 h without any sign of corrosion or delamination. EIS analysis with PDP parameters suggested the formation of protective layer; that is responsible for the corrosion resistance. Europium has unique ability to form a protective oxide layer acting as a barrier layer that could prevent the penetration of corrosive electrolyte to the underlying metal substrate. [ABSTRACT FROM AUTHOR]

Magnesium alloys are widely used for orthopedic implants due to their biocompatibility and biodegradability. However, their low corrosion resistance limits their application, particularly in physiological environments. The goal of this study is to examine how a three-layer coating, consisting of MOF/3D rGO/PCL, affects the corrosion resistance and in vitro biocompatibility of a biodegradable Mg–Mn–Zn alloy in a simulated body fluid (SBF). Corrosion behavior was evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy. The results demonstrate a significant enhancement in the corrosion resistance of the modified alloy. Additionally, cell culture experiments were conducted to investigate the biocompatibility of the coatings. The data from the methylthiazole tetrazolium (MTT) and alkaline phosphatase (ALP) bioassays indicate a substantial improvement in the growth process of MC3T3-E1 osteoblastic cells and an increase in ALP activity in SBF. This confirms the non-toxicity and biocompatibility of the synthesized coating in the SBF solution. The findings of this study will be valuable for the development of biodegradable materials in biomedical applications. [ABSTRACT FROM AUTHOR]

The commercialization of magnesia–air batteries (Mg–air) necessitates the development of highly efficient, cost-effective, and durable electrocatalysts for the oxygen reduction reaction (ORR), replacing expensive and unstable precious metal electrocatalysts. A hard template-assisted synthesis of FeCo nanoparticles immobilized on N-doped porous carbon (Fe–Co–C–N) for the ORR is reported. The half-wave potential of Fe–Co–C–N for ORR (E1/2 = 0.88 V vs. RHE) is elevated by 40 mV compared to that of 20 wt% Pt/C (E1/2 = 0.84 vs. RHE). The catalyst exhibits exceptional catalytic performance and remarkable stability. The discharge voltage of the Mg–air battery, utilizing Fe–Co–C–N as the cathode catalyst (1.29 V), surpasses that of the battery employing 20 wt% Pt/C as the cathode catalyst (1.28 V). The Mg–air battery with Fe–Co–C–N as the cathode catalyst exhibited excellent discharge stability and maintained a stable discharge for over 200 hours. The present study offers valuable insights into the structural design and regulatory mechanisms governing the performance of M–N–C catalysts in Mg–air batteries. [ABSTRACT FROM AUTHOR]

Porous hexagonal nanoplatelets of mixed metal oxide (MMO) derived from the calcination of MgAl layered double hydroxide exhibits a CO2 sorption capacity of 1.99 mmol g−1 at 30 °C, with a retention of 87% sorption capacity over 10 carbonation–decarbonation cycles and a CO2 sorption capacity of 1 mmol g−1 at 200 °C with a 40% increase in capacity over 10 cycles. The high sorption capacity is attributed to the porous nanoplatelet structure of the MMO with a BET surface area of 115 m2 g−1, which enables increased CO2 diffusion. Upon partially replacing magnesium with calcium (33, 50 and 66 mol%), the CO2 sorption capacity of the MMO increases with an increase in temperature. MMO derived from LDH, in which 66% of magnesium is replaced by calcium (MgCaAl-66), delivers CO2 sorption capacities of 1.38, 1.31, 2.50, 4.85 and 7.75 mmol g−1 at 200, 300, 350, 400 and 600 °C, respectively, which is significant for application in the sorption-enhanced water gas shift (SEWGS) process. MgCaAl-66 MMO exhibits a sorption capacity of 1 mmol g−1, which is stable over 10 cycles at 200 °C, and a sorption capacity of 3.68 mmol g−1 at 400 °C with 85% capture efficiency retention over 10 cycles. While the incorporation of Ca2+ serves multiple purposes such as increasing basic defect sorption sites and improving stability to repress the sintering-induced limitation of MMO over sorption cycles, the porous nanoplatelets act as individual sorbent units resisting volume changes through carbonation–decarbonation cycles. [ABSTRACT FROM AUTHOR]

Magnesium borate whiskers were used to prepare a hierarchical microstructure on cordierite ceramic substrate through the precipitation-molten salt method. The La 2-X Ce X Zr 2 O 7 catalyst was then loaded onto the magnesium borate whiskers to form the hierarchical microstructure. The Ce-doped catalysts exhibited a significant improvement in the catalytic activity of soot combustion compared to the La 2 Zr 2 O 7 catalyst. The study employed various techniques to characterize the structural morphology and phase composition, including scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Fourier transform-infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The growth of Magnesium borate whiskers (Mg 2 B 2 O 5) with diameters of 100–200 nm and lengths of 2–5 μm were grown and tightly bonded to the cordierite ceramic substrate to mimic the structure of human respiratory system cilia. This could improve the filtration efficiency of soot in car exhaust. BET analysis showed that the specific surface area of cordierite increased from 0.684 m2/g to 1.363 m2/g after whisker growth. The study confirmed that the whiskers were firmly attached to the cordierite ceramic substrate, as demonstrated by the binding strength experiments. The addition of Ce metal has been found to significantly enhance soot combustion due to the presence of more active oxygen species and superior mobility of lattice oxygen species with more oxygen vacancies. The catalyst's intrinsic redox property was characterized using X-ray photoelectron spectroscopy (XPS) and H 2 temperature-programmed reduction (H 2 -TPR). The semi-quantitative thermogravimetric analysis (TG-DTG) and the temperature-programmed oxidation (TPO) of catalysts showed that Z-La 1.9 Ce 0 · 1 Zr 2 O 7 exhibited the highest catalytic activity for soot combustion, with an ignition temperature of 268 °C, a peak temperature of 418 °C, and a temperature of 90 % soot conversion of 464 °C. Furthermore, cyclic stability experiments demonstrate that the Z-La 1.9 Ce 0 · 1 Zr 2 O 7 catalyst exhibits excellent structural stability and consistent catalytic performance. This distinctive microstructure holds great potential for applications in the field of DPF. [ABSTRACT FROM AUTHOR]

Aluminum and magnesium are the lightest structural metals, and therefore, various alloys based on them are widely used in both, automotive and aerospace industries. However, aluminum and magnesium are very easily affected by atmospheric and aqueous corrosion, and, therefore, the alloying elements should enhance their corrosion stability. In this work, the thermodynamic analysis of phase and chemical equilibria involving aluminum and magnesium alloys doped with silicon in oxygen–containing air environments, as well as the analysis of chemical and electrochemical equilibria involving these alloys in aqueous environments is conducted. The phase and chemical equiliibria in the Al–Mg, Al–Si, Mg–Si, and Al–Mg–Si systems at 298 K are considered, and the thermodynamic activities of the components of common Al–Mg–Si system alloys are calculated. The invariant chemical equilibria in the systems Al–Mg–O, Al–Si–O, Mg–Si–O at 298 K are considered, the isothermal section of the state diagrams of these systems are plotted, and the oxidation scheme of the Al–Mg–Si system alloys in excess oxygen is proposed. The chemical and electrochemical equilibria in the Al–Mg–Si–H2O system at 298 K are considered and presented in form of the activity – pH and the potential – pH diagrams, and the oxidation of the Al–Mg–Si system alloys in aqueous environments is discussed. [ABSTRACT FROM AUTHOR]

Traditional chemotherapy drugs for cervical cancer often cause significant toxic side effects and drug resistance problems, highlighting the urgent need for more innovative and effective treatment strategies. Magnesium alloy is known to be degradable and biocompatible. The release of degradation products Mg2+, OH−, and H2 from magnesium alloy can alter the tumor microenvironment, providing potential anti-tumor properties. We explored the innovative use of magnesium alloy biomaterials in the treatment of cervical cancer, investigating how various concentrations of Mg2+ on the proliferation and cell death of cervical cancer cells. The results revealed that varying concentrations of Mg2+ significantly inhibited cervical cancer by arresting the cell cycle in the G0/G1 phase and inducing apoptosis in SiHa cells, effectively reducing tumor cell proliferation. In vivo experiments demonstrated that 20 mM Mg2+ group had the smallest tumor volume, exhibiting a potent inhibitory effect on the biological characteristics of cervical cancer. This enhances the therapeutic potential of this biomaterial as a local anti-tumor therapy and lays a theoretical foundation for the potential application of magnesium in the treatment of cervical cancer. [ABSTRACT FROM AUTHOR]

The present work involves in a novel approach of studying the material characteristics of AZ31 alloy by varying the cooling method in powder metallurgy and particle size of the matrix material. It also has a novel approach of reinforcing AZ31 alloy with quarry dust and providing self oxide coating to the material in a distinct way for corrosion resistance. The alloy is prepared through powder metallurgy with a pressure of 675 MPa, sintered at 540 ºC, with one hour of soaking. The Scanning Electron Microscopy images are taken to analyse the microstructure. Wear and corrosion studies are done to analyse the effect of parameters. Optimisation for wear is also done with Taguchi method. The AZ31 samples reinforced 5, 10 and 15% of quarry dust are prepared and studied for mechanical properties. The material prepared using 75–150 micron range, cooled in still air cooling and with 5% reinforcement has shown higher values of compressive strength and microhardness. The alloy provided with self-oxide coating has shown higher resistance to corrosion than that of uncoated alloy and the composite. [ABSTRACT FROM AUTHOR]

The replacement of traditional materials like steel and Fe with lightweighted solutions, such as Al, Mg and composites has rapid development in science and technology. This study looks into Mg alloys which is expected to have rising impact on industrial trends in the future with material consumption, balanced performance and economic effects. Joining dissimilar materials together has never been easy and so the paper gives a brief theory of the advanced joining methods, laser beam welding (LBW) of distinct lightweight materials like Mg alloys, and its influences on laser parameters. Additionally, all experimental analyses of interlayer or filler materials reinforced by the weld joint of Mg alloys are studied. Their imitating results on the Mg alloys’ microstructure and properties to advance the weldability of the joint to repel failure, as well as their knowledge of the fundamentals, current trends and future approaches in the advanced joining of lightweight materials. [ABSTRACT FROM AUTHOR]

Purpose: To improve the corrosion resistance of magnesium alloys, the construction of protective coatings is necessary to extend the service life of Mg-based materials. Design/methodology/approach: SiO2 nanoparticles modified by dodecyltrimethoxysilane (DTMS) were added to the PP and a superhydrophobic Mg(OH)2/PP-60mSiO2 composite coating was fabricated on the surface of AZ31 magnesium alloy via the hydrothermal method and subsequently the immersion treatment. Findings: Hydrophilic SiO2 nanoparticles become hydrophobic after modified by DTMS, showing a higher dispersibility in xylene. By incorporating modified SiO2 nanoparticles into the composite PP coating, the hydrophobicity of the layer was enhanced, resulting in a contact angle of 166.3° and a sliding angle of 3.4°. It also improved the water repellency and durability of the coating. Furthermore, the intermediate layer of Mg(OH)2 significantly strengthened the bond between the PP layer and the substrate. The Mg(OH)2/PP-60mSiO2 composite coating significantly enhances the corrosion resistance of the magnesium alloy by effectively blocking the infiltration of the corrosion anions during corrosion. The corrosion current density of the Mg(OH)2/PP-60mSiO2 composite coating is approximately 8.23 × 10–9 A·cm-2, which can achieve a magnitude three times lower than its substrate, making it a promising surface modification for the Mg alloy. Originality/value: The composite coating effectively and durably enhances the corrosion resistance of magnesium alloys. [ABSTRACT FROM AUTHOR]

Magnesium-based alloys and composites have potential as biodegradable materials due to their moderate biodegradability, biocompatibility, and usefulness, but their mechanical strength limits their clinical use. The study synthesised a WE43-based alloy with calcium (Ca) and zinc (Zn), then reinforced it with nano reinforcements (hydroxyapatite, beta-tricalcium phosphate, graphene, and bioglass) through stir casting to create four nanocomposites. The microstructural and mechanical properties were examined to assess Ca and Zn's influence and determine the most effective reinforcement. The result showed that Ca and Zn-modified alloys and all nanocomposite materials have two additional phases, LPSO and Ca 2 Mg 6 Zn 3 , compared to the monolithic WE43 alloy. With the addition of Ca and Zn, S-2 saw significant increases in ultimate tensile strength (UTS), tensile yield strength (TYS), and uniform elongation (U.El), reaching ∼246 MPa, ∼144 MPa, and ∼8 %, respectively, while maintaining an elastic modulus of ∼19 GPa. This resulted in improvements of ∼29 %, ∼25 %, and ∼9 % compared to the as-cast WE43. Graphene-reinforced S-4 demonstrated superior mechanical properties with a UTS of 294 MPa, TYS of 194 MPa, U.El of ∼8 %, and an elastic modulus of 24 GPa, representing increases of ∼52 %, ∼69 %, and 6.05 %, respectively, compared to as-cast WE43. Additionally, S-4 exhibited impressive compressive properties, with an ultimate compressive strength (UCS) of 370 MPa, a compressive yield strength (CYS) of ∼185 MPa, and an U.El of ∼26 %. The bioglass-reinforced nanocomposites had a maximum hardness of 74.8 HV, whereas the as-cast WE43 had a maximum toughness of ∼4 J. These enhancements in mechanical properties are attributed to strengthening processes, including thermal mismatch, orowan, and grain refinement mechanisms. Graphene reinforcement shows promise for biodegradable applications. [ABSTRACT FROM AUTHOR]

Bone fractures often require internal fixation using plates or screws. Normally, these devices are made of permanent metals like titanium providing necessary strength and biocompatibility. However, they can also cause long-term complications and may require removal. An interesting alternative are biocompatible degradable devices, which provide sufficient initial strength and then degrade gradually. Among other materials, biodegradable magnesium alloys have been developed for craniofacial and orthopaedic applications. Previously, we tested implants made of magnesium hydroxide and RS66, a strong and ductile ZK60-based alloy, with respect to biocompatibility and degradation behaviour. Here, we compare the effects of dissolving magnesium hydroxide and RS66 cylinders on bone regeneration and bone growth in rabbit condyles using microtomographical and histological analysis. Both magnesium hydroxide and RS66 induced a considerable osteoblastic activity leading to distinct but different spatio-temporal patterns of cancellous and periosteal bone growth. Dissolving RS66 implants induced a prominent periosteal bone formation on the medial surface of the original condyle whereas dissolving magnesium hydroxide implants enhance mainly cancellous bone formation. Especially periosteal bone formation was completed after 6 and 8 weeks, respectively. The observed bone promoting functions are in line with previous reports of magnesium stimulating cancellous and periosteal bone growth and possible underlying signalling mechanisms are discussed. Biodegradable magnesium based implants are promising candidates for use in orthopedic and traumatic surgery. Although these implants are in the scientific focus for a long time, comparatively little is known about the interactions between degrading magnesium and the biological environment. In this work, we investigated the effects of two degrading cylindrical magnesium implants (MgOH 2 and RS66) both on bone regeneration and on bone growth. Both MgOH 2 and RS66 induce remarkable osteoblastic activities, however with different spatio-temporal patterns regarding cancellous and periosteal bone growth. We hypothesize that degradation products do not diffuse directionless away, but are transported by the restored blood flow in specific spatial patterns which is also dependent on the used surgical technique. [Display omitted] [ABSTRACT FROM AUTHOR]

Magnesium as a biodegradable material offers promising results in recent studies of different maxillo-facial fracture models. To overcome adverse effects caused by the fast corrosion of pure magnesium in fluid surroundings, various alloys, and surface modifications are tested in animal models. In specified cases, magnesium screws already appeared for clinical use in maxillofacial surgery. The present study aims to compare the bone healing outcome in a non-load-bearing fracture scenario of the forehead in sheep when fixed with standard-sized WE43 magnesium fixation plates and screws with plasma electrolytic oxidation (PEO) surface modification in contrast to titanium osteosynthesis. Surgery was performed on 24 merino mix sheep. The plates and screws were explanted en-bloc with the surrounding tissue after four and twelve weeks. The outcome of bone healing was investigated with micro-computed tomography, histological, immunohistological, and fluorescence analysis. There was no significant difference between groups concerning the bone volume, bone volume/ total volume, and newly formed bone in volumetric and histological analysis at both times of investigation. The fluorescence analysis revealed a significantly lower signal in the magnesium group after one week, although there was no difference in the number of osteoclasts per mm2. The magnesium group had significantly fewer vessels per mm2 in the healing tissue. In conclusion, the non-inferiority of WE43-based magnesium implants with PEO surface modification was verified concerning fracture healing under non-load-bearing conditions in a defect model. Titanium implants, the current gold standard of fracture fixation, can lead to adverse effects linked to the implant material and often require surgical removal. Therefore, degradable metals like the magnesium alloy WE43 with plasma electrolytic oxidation (PEO) surface modification gained interest. Yet, miniplates of this alloy with PEO surface modification have not been examined in a fracture defect model of the facial skeleton in a large animal model. This study shows, for the first time, the non-inferiority of magnesium miniplates compared to titanium miniplates. In radiological and histological analysis, bone healing was undisturbed. Magnesium miniplates can reduce the number of interventions for implant removal, thus reducing the risk for the patient and minimizing the costs. [Display omitted] [ABSTRACT FROM AUTHOR]

The high coefficient of thermal expansion (CTE) of magnesium alloys leads to poor thermal dimensional stability and limits its application in the electronic field. This work focused on understanding the effect of rare earth (RE) on the thermal expansion behavior of Mg and attempted to tailor the CTE with SiC particulates. Composites were manufactured by gravity casting with ultrasonic dispersion treatment. The effect of 3 wt.% RE (Sm, Nd, Gd, Y) on the microstructure and thermal expansion behavior of the Mg alloys was explored. Adding RE can lead to the formation of RE-containing second phases and marginally decreased the CTE of magnesium. The CTEs of Mg-3Sm, Mg-3Nd, Mg-3Gd and Mg-3Y alloys were 27.3 × 10−6/°C, 27.0 × 10−6/°C, 27.2 × 10−6/°C and 27.8 × 10−6/°C, respectively. The influence of SiCp on the thermal expansion behavior of Mg-3Y was also investigated. The SiCp promoted the precipitation of Mg24Y5 phase in the extruded Mg-3Y/SiCp composites and significantly reduced the CTE. The CTEs of Mg/3SiC, Mg-3Y/1SiC, Mg-3Y/3SiC and Mg-3Y/5SiC were 27.4 × 10−6/°C, 26.8 × 10−6/°C, 26.6 × 10−6/°C and 23.3 × 10−6/°C, respectively. Rule of mixture, the Turner model and the Kerner model were utilized to predict the CTE of the Mg-3Y/xSiCp (x = 1, 3, 5) composites. The predictions of the Kerner model show a better correlation with the experimental results. [ABSTRACT FROM AUTHOR]

A novel ultra-sound assisted method was used to grow zinc-metal organic framework (Zn-MOF) film on magnesium oxide/hydroxyapatite (MgO/HA) composite layer developed using plasma electrolytic oxidation (PEO) on Mg-5Sn-0.2Mn-0.2Ca alloy. The microstructure surface roughness and microhardness tests were performed on the samples to evaluate the mechanical properties of the coatings. The electrochemical corrosion test was performed to evaluate the corrosion resistance of the coated Mg alloy. Further, an in-vitro bioactivity test was performed to study the biocompatibility and bioactivity of the coated alloy, which is an essential aspect of biomedical applications. Results showed that the MgO/HA composite coating was helpful in the in-situ growth of the Zn-MOF particles by mechanically interlocking them. Further, incorporating hydroxyapatite in the coating could also increase the bioactivity. The study also confirmed that the bi-layer coating of Zn-MOF on the MgO/HA composite layer improved the surface roughness, hardness, biocorrosion resistance, and bioactivity making it more likely to be used for orthopedic internal fixation devices. [ABSTRACT FROM AUTHOR]

The aim of the research was to determine the possibility of producing and using layered composites made of aluminium and magnesium alloys Al1050-AZ31-Al1050. The use of layered composites often results from economic conditions. The work analyzed the current research, technological and production potential, as well as selected microstructural phenomena occurring in the tested multilayer materials and the effects of the rolling process. The material for the study was obtained using the explosion welding technology, one of the few enabling universal joining of often difficult-to-weld metals. The rolling process was carried out on a semi-industrial duo rolling mill with a roller diameter of Ø300 mm. The composite input material for the rolling process was heated to a temperature of 380 °C. The effect of the rolling process on the distribution of metal pressure forces on the rolls, the geometric parameters and the microstructural changes occurring in the plastically formed layered composite were an-alysed, and the energy gain from using a structure in which the currently used aluminium com-ponents were replaced with the tested composite was estimated. The research results presented in this paper prove that in the rolling process of the layered composite there are differences in the deformation values of the Al1050 and AZ31 layers. These differences are caused by the properties of the materials combined into the layered composite. The use of the proposed composite material in industrial conditions will enable the weight of selected elements to be reduced by up to 60%, which will have a positive impact on the energy efficiency of the entire structure. [ABSTRACT FROM AUTHOR]

AbstractAn investigation has been performed to study the compatibility of machining AZ91 magnesium alloy in dry conditions using uncoated and CVD diamond-coated WC-Co inserts. The machining characteristics such as built-up edge (BUE) formation, surface roughness, cutting forces and chip morphology were studied at the cutting speeds, 350, 650 and 950 m/min. The results revealed severe adhesion of the AZ91 Mg alloy on the uncoated WC-Co inserts with increasing cutting speed and contributed to an increase in surface roughness and cutting forces. The CVD diamond-coated inserts have shown negligible built-up edges at various cutting speeds due to their unique properties like low coefficient of friction, low chemical affinity and high thermal conductivity. Snarled types of long continuous chips were observed while machining with CVD diamond-coated WC-Co inserts, whereas short continuous chips were observed with uncoated WC-Co inserts. [ABSTRACT FROM AUTHOR]

Metal hexacyanoferrates (HCFs) are regarded as promising cathode materials for potassium‐ion batteries (PIBs) on account of their low cost and high energy density. However, the difficult‐to‐remove [Fe(CN)6] vacancies and crystal water lead to structural instability and capacity deterioration as well as the stereotype of poor thermostability of conventional HCFs. Herein, we report (100) face‐oriented potassium magnesium hexacyanoferrate (KMgHCF) nanoplates with low [Fe(CN)6] vacancies and high crystallinity, enabling thermostability up to 550 °C, high‐temperature carbon coating and crystal water elimination. The as‐obtained KMgHCF/C nanoplates exhibit superior potassium storage properties, including a large reversible capacity of 84.6 mAh g−1, a high voltage plateau of 3.87 V, excellent long‐term cycling performance over 15000 cycles and high rate capability at 5 A g−1. The unprecedented cycling stability of KMgHCF/C is attributed to the synergistic effect of a highly reversible two‐phase reaction, low [Fe(CN)6] vacancies and no crystal water, a specially exposed steady (100) surface, and a protective carbon coating. This work provides a new material selection and modification strategy for the practical application of HCFs in PIBs. [ABSTRACT FROM AUTHOR]

This study, aims to weld the 5.2 mm thick AZ31 magnesium alloy with conventional friction stir welding at the highest joining efficiency. As a result of the experiments, 88% joining efficiency in tensile strength has been obtained at 1250 rpm, 400 mm.min−1 welding parameter. As a result of micro–macrostructure photographic examinations of the samples joined with these parameters, it is seen that the joining is fully realized. Samples joined with these parameters have been used in fatigue tests. According to the strain‐controlled low cycle fatigue test results performed on welded and base metal samples, the base metal samples have exceeded the 50,000‐cycle limit without failure, with an elongation rate of 0.3%, and the welded samples with an elongation rate of 0.2%. Low cycle fatigue parameters of welded and base metal samples have been obtained according to the Coffin‐Manson‐Basquin equation. [ABSTRACT FROM AUTHOR]

This investigation explores the impact of incorporating graphene (Gr) reinforcement on the microstructure, mechanical properties, corrosion behavior, and biocompatibility of a composite derived from a magnesium–calcium (Mg–Ca) alloy. Two concentrations of Gr (0.1% and 0.2%) were introduced to an Mg–Ca alloy. The addition of 0.1% Gr resulted in a refined grain structure, enhancing both tensile and compression strength. However, electrochemical analysis and immersion testing revealed an increase in corrosion rate (Rw${R}_w$) with the incorporation of Gr. Although the corrosion rate of the Mg–Ca‐0.1%Gr composite was comparable to that of Mg–Ca, the Mg–Ca–0.2%Gr exhibited higher corrosion rates attributed to the enhancement of micro‐galvanic corrosion. Interestingly, cell survival rate tests demonstrated improved biocompatibility for the Mg–Ca–0.1%Gr sample, emphasizing its potential for applications in the biomedical domain, which requires enhanced mechanical strength, corrosion resistance, and biocompatibility. [ABSTRACT FROM AUTHOR]

Fabrication of Mg alloys using the additive manufacturing process is quite challenging owing to high oxidation and volatile nature at high temperatures. The present study investigates the effect of wire feed speed (WFS) and travel speed (TS) on single tracks of AZ31 Mg alloy fabricated using the cold metal transfer wire arc additive Manufacturing (CMT-WAAM) process. The WFS and TS of CMT-WAAM are optimized to achieve better deposition quality. An increase in WFS increased the width, height, penetration depth, and heat-affected zone of single tracks. In addition, increasing TS decreased the deposited tracks' contact angle and height. The average grain size at the interface zone, center and top portion of single tracks are 35, 42, and 60 μm. The x-ray diffraction results show only the presence of primary phase α-Mg; interestingly, the β-Mg17Al12 and η-Al8Mn5 secondary phases are identified by SEM + EDS and TEM images. The microhardness increased from the substrate to the top section of single tracks due to the increased volume fraction of secondary-phase particles. Based on the best-chosen process parameters obtained from single-track deposition, a multilayer AZ31 Mg thin wall is deposited. The UTS, YS, and % EL of the deposited thin wall in travel direction (TD) are 222 MPa, 102 MPa, and 18%, while in build direction are 202 MPa, 110 MPa, and 14%, respectively. The tensile strength and elongation % of TD and BD samples exhibited comparable properties and were higher than cast AZ31 Mg alloy. [ABSTRACT FROM AUTHOR]

Hydrogen is emerging as a crucial clean energy carrier, but storage challenges remain. Magnesium has the highest hydrogen storage capacity among metals, yet its high thermodynamic stability, desorption temperature, and slow reaction rates hinder practical use. Identifying suitable metal alloys for magnesium remains challenging. This study employs ML-framework with 13 inputs to predict H 2 storage and release capacity (2 outputs) in Mg-based alloys, with database comprises 792 storage and 279 release observations. Linear-models initially performed poorly, leading to the development of nonlinear models such as tree ensembles, kernel based methods, and neural networks. After hyperparameter tuning with 5-fold cross-validation, an ANN with Bayesian regularization achieved higher accuracy in predicting hydrogen gravimetric capacity (R2 = 0.86 for storage, R2 = 0.93 for release for test data). With this model, post-analysis revels key-factors influencing hydrogen uptake are particle size, Mg composition, and pressure, while temperature and time significantly affect hydrogen release. Finally, this study identifies operating ranges for these factors, providing insights for improving/accelerating Mg based hydrogen storage materials development. [Display omitted] • ML framework for understanding and prediction of H 2 gravimetric capacity. • Constructed a database comprising of Mg-based metal alloys and operating conditions. • Several ML models developed through 5-fold cross validation & holdout method. • ANN-BR model with tan-sigmoid activation function resulted higher prediction accuracy. • Input contribution & PDP analysis unfolded significant parameters and operable range. [ABSTRACT FROM AUTHOR]

In this work, five alloys, Al − Mg, Al − Ce, Al − Ti, Al − Mg − Ce and Al − Mg − Ti, were prepared, and the electrochemical properties and discharge behavior of pure Al and these alloys were investigated in 4 M KOH solution. Corrosion experiments and electrochemical tests were performed, including open circuit potential test, electrochemical impedance spectroscopy test and polarization curve test. The performance of Al − air batteries based on these anodes was investigated by constant current discharge and V − j discharge tests. The surface state of the Al anodes after discharge was analyzed by scanning electron microscope and energy dispersive spectrometer. The results show that the addition of magnesium, cerium, and titanium to Al enhances its corrosion resistance, discharge voltage, peak power density, and specific capacity. Among the binary alloys, Al − Mg demonstrates superior corrosion resistance and higher no − load activity, while Al − Ce and Al − Ti exhibit higher discharge voltages and peak power densities. Additionally, the ternary alloys Al − Mg − Ce and Al − Mg − Ti, prepared using Al − Mg as the matrix, significantly reduce the corrosion rate and improve discharge performance. Al − Mg − Ce shows a maximum voltage of 1.21 V at 50 mA·cm− 2, while Al − Mg − Ti displays a maximum voltage of 0.899 V at 100 mA·cm− 2, with a peak power density of 97.0 mW·cm− 2, surpassing that of Al − Mg − Ce (83.4 mW·cm− 2) and pure Al (72.8 mW·cm− 2). However, Al − Mg − Ti exhibits lower anode utilization compared to all binary alloys, while Al − Mg − Ce demonstrates higher anode utilization than Al − Mg, albeit slightly lower than that of Al − Ce and Al − Ti. The study highlights the potential of Al − Mg − Ce and Al − Mg − Ti alloys as effective strategies to enhance the performance of Al − air batteries. These findings contribute to the advancement of high − performance Al anodes and the optimization of Al − air battery design. [ABSTRACT FROM AUTHOR]

It has been demonstrated that Sr is a beneficial additive element to Mg alloys and could effectively upgrade the properties of Mg alloys. However, the local structure and thermophysical properties of Mg–Sr, which are important properties of the alloy, have rarely been reported. This work applied atomistic simulations, assisted by deep learning potential (DPL), conducted on the Mg–Sr liquid alloy to reveal its local structure and thermophysical properties. The reliability of the trained DPL model was thoroughly validated by the root-mean-square errors, energy and force comparison results, and local structure reproducibility. The radial distribution function and structural factor were adopted to assess the short-range and intermediate-range ordering of the Mg–Sr liquid alloy, whose component and temperature dependence were analyzed. Mg–Sr alloy is more compact in the Mg-rich system; all the ordering is temperature-negatively dependent. Densities, self-diffusion coefficients, and shear viscosities of Mg–Sr liquid alloys containing different Mg concentrations, covering the temperature range of 1100–1400 K, were predicted by deep learning molecular dynamics simulation, and the corresponding databases were established. The enthalpies of mixing and elemental activities of Mg–Sr liquid alloys at 1100 K were reliably evaluated. The mixing enthalpy is less than zero, and the dependence of the Mg and Sr activities on the Mg concentration presents a downward concave shape that deviates from Raoul's law, forming a negative deviation. Overall, this present study provides theoretical foundation and directional guidance for the development of Mg–Sr alloys. [ABSTRACT FROM AUTHOR]

Rare‐earth (RE) silicates environmental barrier coatings (EBCs) are prone to accelerate failure resulted from molten calcium–magnesium–aluminum silicate (CMAS), which presents significant challenges to the design and development of durable EBCs. In this study, X1‐Gd2SiO5 and X2‐Er2SiO5 coatings were explored on their corrosion resistance to CMAS melts with different Ca/Si ratios (1.1, 0.75, 0.64, and 0.42) at 1350°C for 25 and 50 h, respectively. Results showed that with the Ca/Si ratio increasing, CMAS viscosity decreased and a more intense corrosion reaction with coatings occurred. Garnet phase was only observed in X2‐Er2SiO5 coating corroded by CMAS with high Ca/Si ratios, which could be beneficial for improving corrosion resistance. The X2‐Er2SiO5 phase, which is composed of [SO4] and [REO6]/[REO7] polyhedrons, exhibits better corrosion resistance due to its more stable crystal structure, lower reactivity with CMAS, and the radius difference between the RE ions and Ca2+. [ABSTRACT FROM AUTHOR]

In order to enhance the performance of magnesium alloy and galvanized steel welds, ultrasonic vibration was applied to the laser welding process, and the effect of ultrasonic on mechanical properties was verified through experimental methods. The laser welding system for the lap weld seam was designed, and the ultrasonic vibration module and image detection module were added, which can obtain the influence of ultrasonic vibration on the molten pool area. Under the conditions of ultrasonic vibration power of 1000 W and 0 W, the characteristics of the weld pool area, metallographic structure, tensile strength, fracture morphology, hardness, residual stress, wear resistance, and corrosion resistance of the weld specimen were compared. The image data acquisition structure indicated that ultrasonic vibration can effectively reduce the ineffective area of the molten pool and make the energy in the molten pool more concentrated. Under the influence of ultrasonic vibration, the maximum molten pool area decreased to 5.38 mm2, with a variation range of 3.9 %, and the proportion of pores was greatly reduced. Research found that ultrasonic vibration can significantly improve the microstructure characteristics of the fusion welding zone, with an average grain size reduced to 23 μm. The reduction of grain size and refinement of microstructure were beneficial to the improvement of mechanical properties of magnesium alloy joints, with a yield strength increase of 6.5 %. Ultrasonic vibration had little effect on the hardness of the heat affected zone, it can increase the average hardness of the weld zone by more than 5 % and reduce the maximum residual stress by more than 50 %. Under different pressure and friction speed conditions, the maximum wear amount can be reduced by more than 25 %. At the same time, the resistance to oxidation corrosion and electrochemical corrosion also can be improved to a certain extent. [ABSTRACT FROM AUTHOR]

This work examines the void growth and coalescence in isotropic porous elastoplastic solids with sigmoidal material hardening via finite element three-dimensional unit cell calculations. The investigations are carried out for various combinations of stress triaxiality ratio (T ) and Lode parameter (L ) and consider a wide range of sigmoidal hardening behaviors with nominal hardening rates spanning two decades. The effect of L is considered in the presence and in the absence of imposed shear stress. Our findings reveal that depending on the nature of sigmoidal hardening the cell stress-strain responses may exhibit two distinct transitions with increasing stress triaxiality (T ). Below a certain lower threshold triaxiality the stress-strain responses are sigmoidal, while above a certain higher triaxiality they exhibit softening immediately following the yield. Between these threshold levels, the responses exhibit an apparent classical rather than sigmoidal strain hardening. The sigmoidal hardening characteristics also influence porosity evolution, which may stagnate before a runaway growth up to final failure. For a given L , an imposed shear stress adversely affects the material ductility at moderate T whereas at high T it improves the ductility. Finally, we discuss the role of material hardening and stress state on the residual cell ductility defined as strain to final failure beyond the onset of coalescence. [ABSTRACT FROM AUTHOR]

In the present work, grain‐refined WE43 magnesium alloy was produced by friction stir processing to investigate the in vitro degradation behavior targeted for temporary bone implant applications. Friction stir processing resulted in significant grain refinement (from 46±4.2 μm to 16.1±5.4 μm) as observed from microstructural studies. Increased wettability was observed from the contact angle measurements in grain‐refined WE43 alloy. The corrosion behavior of the base alloy and the grain refined alloy assessed by potentiodynamic polarization tests demonstrated the influence of the smaller grain size and decreased intermetallics on enhancing corrosion resistance. Immersion studies carried out in simulated body fluids for one week indicated a quick development of the protective magnesium hydroxide on the surface of grain‐refined WE43 alloy compared with the base alloy. The deposition of the mineral phases from the immersed solution on the surface of the samples was studied by scanning electron microscopy and x‐ray diffraction analysis to assess the effect of microstructure on the biomineralization. Promisingly, grain refined WE43 exhibited relatively excellent mineral deposition which further helped to control the degradation of the alloy. The weight loss measurements of the samples from the immersion tests were also in good agreement with the electrochemical test results. Hence, the results demonstrate the promising role of grain refinement by friction stir processing in tailoring WE43 magnesium alloy with better degradation behavior for temporary bone implant applications. [ABSTRACT FROM AUTHOR]

In order to improve the mechanical property prediction accuracy of AZ80 magnesium alloy, sparrow search algorithm (SSA) is optimized by the tent chaotic mapping (TCM) algorithm, yielding TCMSSA, and TCMSSA is employed to improve extreme learning machine (ELM) model for obtaining TCMSSA-ELM model. TCMSSA-ELM model, along with the traditional ELM model, are both utilized to predict the stress of AZ80 magnesium alloy in a temperature range of 523 K to 673 K and a strain rate range of 0.001s− 1 to 1s− 1. Comparative analysis is conducted to evaluate the performance differences between the two models. The results indicate that compared with ELM model, the predicted values of TCMSSA-ELM model are closer to the experimental data and the ideal 45° line, proving the higher prediction accuracy of TCMSSA-ELM model. In addition, through algorithmic improvements, the maximum reduction of MAPE is 85.422% and the maximum determination coefficient reaches 0.99956, implying that TCMSSA greatly improves the prediction precision of ELM model. The related results offer a new optimization strategy and model to predict the mechanical property of AZ80 magnesium alloy in each molding stage, and provide a technical reference for applying intelligent algorithms to alloy design. [ABSTRACT FROM AUTHOR]

Recently, superhydrophobic magnesium (Mg) alloys are extensively investigated due to their promising applications in corrosion protection and resistance to bacterial adhesion. However, superhydrophobic surfaces may not be conducive to the osteogenic effect of the coated Mg alloys, which limits their clinical application as implants. Herein, the lauric acid (LA)/MoS 2 /Hydroxyapatite (HA) (LMH) superhydrophobic composite coatings were synthesized on AZ31B Mg alloy by hydrothermal process and hydrophobic treatment. The coated Mg alloy had favorable superhydrophobicity, as evidenced by a contact angle measurement of approximately 151.8°. After 3 min of ultrasonic treatment, the contact angle of the coated Mg alloy decreased from 151.8° to 63.5°, which was attribute to the sonothermal effect that changes the surface energy of the coating, hereby removing the air layer at the superhydrophobic interface. Compared to the bare Mg alloy, the electrochemical impedance of the LMH-2.0 superhydrophobic composite coating increased by two orders of magnitude to 89.611 ± 0.593 kΩ cm2. In vitro antibacterial tests showed that the antibacterial efficiency of LMH-2.0 superhydrophobic coating against both S. aureus and E. coli is more than 99% with the assistance of ultrasonic. Meanwhile, the cell fluorescence staining experiments exhibited that the superhydrophobic coating featuring convertible wettability exhibited promising early cell growth and adhesion. The superhydrophobic coatings with wettability transition on magnesium alloys are expected to be ideal modification coatings for degradable implant materials. [ABSTRACT FROM AUTHOR]

This study investigated the influence of corrosion-induced deterioration of the tensile properties of a Mg-1 wt.% Ca alloy on the performance of a coronary artery stent model fabricated using the alloy wire. Finite element analysis was used to determine the change in various characteristics of the model when immersed in a biosimulation aqueous solution (Earle's Balanced Salt Solution). Results from tensile tests on wires fabricated from the alloy (non-treated versus ultrasound-assisted casting (US)) were used as input to a shape optimisation study of the stent, which aimed at reducing stent strut thickness and minimising corrosion-related parameters such as equivalent plastic strain and residual stress. For each of the characteristics, it was found that the US treatment produced a more desirable result compared to the stents modelled using non-treated material data; for example, the decrease in strut thickness, equivalent plastic strain, and residual stress were each markedly greater, while keeping the stent's functionality. These results suggest that US-treated Mg-1 wt./wt.% Ca alloy may be promising for fabricating biodegradable coronary artery stents. [ABSTRACT FROM AUTHOR]

The tensile plastic deformation of the Mg-1Al-0.5Mn-0.3Gd alloy with transverse direction (TD)-tilted texture have been investigated using the experimental and visco-plastic self-consistent model. The results show that the relative activity of the different deformation mechanisms of the magnesium alloys with TD-tilted texture is related to different tensile mechanical properties and the texture evolution under the tensile plastic deformation is in the rolling direction and TD. Moreover, the tensile mechanical behavior of the magnesium alloys with TD-tilted texture has been further studied by inhibiting the activity of different deformation mechanisms in the TD, which shows that, at the early stage of the tensile plastic deformation, the basal slip has the greatest influence on the magnesium alloy with TD-tilted texture. In addition, the pyramidal slip plays an important role with the greatest influence on the mechanical properties of magnesium alloys with TD-tilted texture at the later stage of tensile plastic deformation. [ABSTRACT FROM AUTHOR]

This research investigates the interpretation of corrosion patterns using unsupervised machine learning techniques. The use of machine learning techniques using unsupervised approaches has emerged as an important tool in analyzing corrosion data. Mitigating corrosion requires a comprehensive understanding of the intricate patterns and underlying factors governing its occurrence. The workflow consists of analysis of data preparation and evaluation of the model building. The experiments are conducted in the laboratory, and the data collected are then transferred to Google Colaboratory for analysis. Based on the conceptual framework, the data were collected using experimental studies, and a comprehensive corrosion dataset of 127 data points was obtained. We used the choice of clustering algorithms that significantly influenced the outcome of our analysis to identify corrosion patterns within the data. The clustering algorithms used in this article include K-means, affinity propagation, and hierarchical clustering. The choice of these algorithms stems from the quality of the dataset's size distribution and the desired number of clusters. The findings strongly affirm that, in the models examined in this study, K-means clustering stands out as the most effective choice. The proposed system outperforms other methods and can serve as a crucial foundation for comprehending the underlying corrosion behavior. [ABSTRACT FROM AUTHOR]

The Guinier–Preston (GP) zones have an important influence on the improvement of the age-hardening level of alloy. We here prepare six kinds of Mg-6Zn-5Al (ZA65) magnesium alloy samples to investigate the microstructural evolution, precipitation behavior, and strengthening mechanism using an optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM), and micro-hardness tests. The finding reveals that the GP zones are observed in non-dendritic alloys experiencing pre-aging at 80°C for 24 h, whose formation creates more nucleation sites and accelerate kinetics for precipitated phases. Consequently, the introduced pre-aging has been successful in promoting the increase of the age-hardening level of non-dendritic alloys. The double-aged non-dendritic alloys show a significantly changed microstructure with a high density of long rod-shaped β1′ precipitations, making the age-hardening level of double-aging much better than that of single-aging, and the peak value 90 HV was obtained 4 h in advance, which is an increase of 4 HV compared with that of the direct aged non-dendritic alloy. The strengthening mechanism of non-dendritic alloys is mainly summarized as grain boundary strengthening, GP zone strengthening, and the shearing strengthening of β1′ and β2′ precipitations. Among these, the GP zone strengthening is a fundamental contributor to improving the age-hardening level. [ABSTRACT FROM AUTHOR]

To improve the microstructure of the Al/Mg composite fabricated by extrusion bonding, a novel method to achieve asymmetric extrusion of Al 7075/Mg EW75 composite is proposed, which uses an off-center setup of the initial billet and symmetric die. Good metallurgical bonding is achieved on the interface by the formation of the Mg23Al30 and Mg17Al12 phases as opposed to the Al3Mg2 and Mg17Al12 phases reported before. The asymmetric extrusion promotes recrystallization, refines the microstructure of the matrix, and weakens the strong basal texture of magnesium, which homogenizes the plastic deformation during loading and alleviates the stress concentration on the intermetallic layer. Asymmetric extrusion delays interface crack formation and improves tensile strength of the extruded composite. [ABSTRACT FROM AUTHOR]

In situ synthesis of aluminum nitride (AlN)-reinforced magnesium alloy composites using ammonia (NH3) gas was investigated. Feasibility of in situ formation of AlN reinforcement was analyzed based on Gibbs energy minimization method. Thermodynamic analysis showed that AlN forms in Mg–Al alloy in the temperature range from 923 K to 1223 K and the oxygen that may be present in the system was detrimental for the formation of nitrides. The thermodynamic analysis also shows that Mg aids in decreasing the oxygen content from the system. Injecting ammonia gas through Mg alloy caused bulk nitridation of the alloy, which led to the formation of AlN-reinforced Mg alloy composites. Presence of hydrogen, which was generated by the dissociation of ammonia, in the alloy getters the trace oxygen in the gaseous precursor, enabling the formation of AlN. For the ammonia injection through the Mg–Al alloy containing 30 wt pct Al at 1173 K and injection time of 70 minutes, the yield of AlN was found to increase with an increase in the flow rate of ammonia. The AlN formed in the melt was 15.42 wt pct AlN for a gas flow rate of 0.04 LPM (liters per minute), and 27.43 wt pct AlN at a flow rate of 0.1 LPM. AlN particles formed in situ are surrounded by the γ-(Mg, Al) phase. X-ray diffraction characterization showed that the composites formed in situ were composed of (Mg), intermetallic γ-(Mg, Al), and AlN phases. Scanning electron microscopy and optical microscopy analyses revealed that the AlN particles formed in situ, dispersed uniformly, and the increase in flow rate increases the dispersion density of AlN particles in the composites. The experimental compositions and phases obtained are included in the constructed Mg–Al–N ternary phase diagram at 1173 K. All experimental data fall in the region of AlN and Mg–Al alloy, which is in validation with the thermodynamic prediction. The experimental obtained amount of AlN in composites as a function of Al content in alloy are in good agreement with the thermodynamic modeled results, which indicates that the formation of AlN in Mg–Al alloy is close to an equilibrium process. [ABSTRACT FROM AUTHOR]

To improve the wear and corrosion resistance, Al-Ni coating was prepared on Mg alloy by laser cladding, and the influence of the laser scanning speed on the microstructure, wear and corrosion resistance of the coatings was systematically analyzed. The results showed that the coatings with different scanning speeds were composed of Al3Ni2, Mg17Al12 and Mg2Al3 phases. The coatings presented fine needle-like grains. Under different scanning speeds, the microhardness of the coatings was 3.3–4.8 times that of the substrate, and the wear volume of the coatings was decreased by 40.08–51.38%. The coating with a laser scanning speed of 600 mm/min had the highest hardness, the best wear and corrosion resistance. [ABSTRACT FROM AUTHOR]

It is of great significance in the field of engineering to repair the surface defects of ZM6 cast magnesium alloy by an arc welding method. Compared with the traditional tungsten inert gas (TIG) welding repair technology, cold metal transfer (CMT) welding repair has the advantages of low heat input, small repair deformation, and high efficiency. It is of great research value to repair the surface defects of ZM6 cast magnesium alloy by CMT welding. In this paper, the effect of CMT welding repair parameters on defect repair forming is systematically studied, and a repair process window free of unfused defects is obtained. The effects of preheating temperature of base material, wire-feeding speed, welding speed, stick-out length of welding wire and shielding gas flow on the spread of magnesium alloy melt and weld formation were investigated by a surface surfacing method. During the welding process, a camera was used to capture images of the arc and droplet features. A pit defect with a depth of 11.5 mm was machined on the surface of the casting, and the effect of five different repair paths on the formation of the repair area was studied. In order to make the repair area have better fusion, reasonable repair parameters are as follows: The preheating temperature range is 310–450 °C, the wire-feeding speed range is 5–7 m/min, the welding speed range is 8–10 mm/s, the stick-out length of the welding wire is 12 mm, the shielding gas flow rate is 20 L/min, and the repair path adopts a continuous linear reciprocating welding path. This study has important significance for guiding the development of CMT repair technology of cast magnesium alloy. [ABSTRACT FROM AUTHOR]

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Highlights To improve the dielectric properties and corona resistance of epoxy resins (EPs), the authors designed and synthesized Si‐B‐Mg/EP nanocomposites and investigated the effects of varying the magnesium elemental content on the dielectric properties, breakdown field strength, corona resistance life, volume resistivity and conductive current of Si‐B‐Mg/EP nanocomposites. The experimental results show that when the molar ratio of Si, B, and Mg in the Si‐B‐Mg composite oxide is 18:2:0.125, the composite has the minor dielectric loss and the most extensive corona resistance life of 401.8 min, which is 4.6 times that of the pure EPs. From the experimental results, the introduction of magnesium can effectively improve the dielectric loss and corona resistance of Si‐B‐Mg/EP composites. Si‐B‐Mg composite oxides were designed and synthesized. Performance analysis of Si‐B‐Mg/EP composites with different magnesium content The introduction of magnesium reduces the dielectric loss of composites. The introduction of magnesium improves the corona resistance life of composites. Si‐B‐Mg/EP composites with both low dielectric loss and high corona resistance. [ABSTRACT FROM AUTHOR]

For decreasing the global cost of corrosion, it is essential to understand the intricate mechanisms of corrosion and enhance the corrosion resistance of materials. However, the ambiguity surrounding the dominant mechanism of calcium‐magnesium aluminosilicate (CMAS) molten salt corrosion in extreme environments hinders the mix‐and‐matching of the key rare earth elements for increasing the resistance of monosilicates against corrosion of CMAS. Herein, an approach based on correlated electron microscopy techniques combined with density functional theory calculations is presented to elucidate the complex interplay of competing mechanisms that control the corrosion of CMAS of monosilicates. These findings reveal a competition between thermodynamics and kinetics that relies on the temperatures and corrosion processes. Innovative medium‐entropy monosilicates with exceptional corrosion resistance even at 1500 °C are developed. This is achieved by precisely modulating the radii of rare earth ions in monosilicates to strike a delicate balance between the competition in thermodynamics and kinetics. After 50 and 100 h of corrosion, the thinnest reactive layers are measured to be only 28.8 and 35.4 µm, respectively. [ABSTRACT FROM AUTHOR]

Multifunctional composite coatings have been extensively used to protect metal substrates from corrosion. However, the use of ionic liquids (ILs) to modify the micro-arc oxidation/layered double hydroxides (MAO/LDHs) composite coating, to our best knowledge, has not been reported for the corrosion protection on metal substrates. It is thus necessary to prepare the ILs-modified MAO/LDHs composite coatings and understand in depth their corrosion resistance and active anticorrosive mechanism. Herein, a composite coating is constructed by introducing the MgAl-LDH modified by a choline 3-morpholinopropanesulfonate [Ch][MOPS] ionic liquid on an MAO film (CM-LDH/MAO). It is found that the CM-LDH/MAO composite coating shows the optimal corrosion protection on magnesium alloy, with a corrosion current density of 8.38 × 10−10 A cm−2, clearly lower than those of the MAO and LDH/MAO coatings. More importantly, a small pitting appears at the edge of the CM-LDH/MAO film only after long-term exposure of 216 h in 3.5 wt% NaCl solution. Such an improvement of corrosion resistance can be ascribed to the synergetic mechanism including the physical barrier of the composite coating, the self-repairing ability of the LDH nanosheets on the microporous flaws of the MAO film, as well as the formation effect of the Mg-based chelates by the adsorption of the [Ch]+ cations and the re-adsorption of the [MOPS]– anions released from the LDH interlayers. [ABSTRACT FROM AUTHOR]

To enhance the corrosion resistance of magnesium alloys, an anti-corrosion composite film was prepared by combining anodic oxidation and sol-gel technology. Experimental results indicate that after anodization at 17.5V for 3 min, the composite film obtained through sealing with an MPTMS-modified sol exhibited significant improvements in physical properties. The thickness of the film reached 24.3 μm, its hardness was measured at 164.7 HV, and it demonstrated good surface uniformity. Electrochemical impedance spectroscopy revealed that the impedance modulus at low frequency (|Z| at 0.01 Hz) increased by nearly two orders of magnitude. Furthermore, this study thoroughly explores the corrosion protection mechanism of the composite film, highlighting the role of the sol-gel layer in occupying micro-pores and micro-cracks to form a denser and more uniform protective layer. The dual-layer protection provided by the combination of anodic oxidation and sol-gel layers significantly enhances the overall corrosion resistance of the magnesium alloy. [ABSTRACT FROM AUTHOR]

Reticulated ceramic filters play an important role in the reduction of non-metallic inclusions in molten steel, which can improve the quality of steel products. In this work, periclase-magnesium aluminate spinel ceramic filters with Al 2 O 3 and TiO 2 functional coatings were fabricated by using microporous MgO powder, respectively. The effects of the functional coatings on their microstructure, properties and purification capacity on molten steel were studied. The filter with Al 2 O 3 functional coating exhibited the best mechanical properties owing to the good rheological properties of the coating slurry, as well as the formation of in-situ spinel layer connection between the Al 2 O 3 functional coating and the microporous MgO layer of the filter substrate. Compared with the filters without functional coating or with TiO 2 functional coating, the filter with Al 2 O 3 functional coating made more Al 2 O 3 inclusions deposit on the filter surface by physical adsorption due to the same chemical composition between the functional coating and inclusions, which significantly improved the adsorption capacity of filter for Al 2 O 3 inclusions in molten steel. Overall, the filter with Al 2 O 3 functional coating had the highest cold compressive strength of 1.4 MPa, a residual retention of cold compressive strength after thermal shock of 65.71 % and an efficiency of 36.56 % in reducing the total oxygen content of the steel. [ABSTRACT FROM AUTHOR]

Available water capacity (AWC), field capacity (θFC), and permanent wilting point (θPWP) are regarded as key physical soil health indicators that directly capture the soil's capacity to store plant available water but are expensive components of a comprehensive soil health analysis. To reduce costs, pedotransfer functions for θFC, θPWP, and AWC were developed from a dataset of 7,232 soil samples with texture, soil organic matter (SOM), permanganate-oxidizable carbon, soil respiration, AWC, θFC, θPWP, wet aggregate stability, and extractable potassium, magnesium, iron, and manganese. Three functions were developed for each property: a full random forest (RF) model containing all variables, a reduced RF model and a multiple linear regression model containing texture and SOM. Pedotransfer functions were validated with an independent dataset that contained 1,406 samples. The full RF models for θFC, θPWP, and AWC reduced the root mean square error (RMSE) by 16.3, 13.3, and 12.8%, compared to multiple linear regression models, respectively. Furthermore, the full RF models for θFC, θPWP, and AWC reduced RMSE by 11.6, 6.7, and 12.8%, compared to the reduced RF model, respectively. Permanganate-oxidizable carbon, wet aggregate stability, and extractable magnesium, potassium, and iron were useful novel predictor variables for improving prediction of θFC and AWC. AWC was sensitive in 20/57 long-term experiments, and full RF models were able to replicate 5/20 of those significant results. New RF pedotransfer functions for θFC, θPWP, and AWC can enhance prediction compared to traditional modeling techniques, fits into existing interpretative frameworks, and improves cost-effectiveness of comprehensive assessments of soil health. [ABSTRACT FROM AUTHOR]

Building formwork is a kind of temporary supporting structure consumable material used in the construction field. In recent years, building formwork has gradually developed to become lighter, more environmentally friendly, and have higher performance. This sets higher requirements for the materials used to make building formwork. There is an urgent need to find a lighter and more durable material for building formwork. Magnesium alloys possess the advantages of low density, high alkali resistance, and high strength. As a building formwork material, it can reduce the weight of formwork and improve its durability. Therefore, a magnesium alloy is considered a material with high potential for building formwork. Currently, magnesium alloy building formwork has attracted the attention of many companies and research and development institutions, with preliminary research applications and good feedback on usage effects. It is highly possible to obtain the opportunity to put it into market application. However, to be applied on a large scale, there are still some important problems that need to be solved. These problems fall into three main areas, including the relatively low processing efficiency of magnesium alloy materials, the unstable price of magnesium alloys, and the fact that the formwork is easily corroded during storage. Firstly, at present, the main processing methods for magnesium alloy building formwork are casting and extrusion, and the production efficiency of both methods needs to be improved. Secondly, high-performance magnesium alloy materials are usually more expensive, which is not conducive to the large-scale application of the formwork. The price of magnesium alloys has fluctuated greatly in recent years, which increases the difficulty of promoting magnesium alloy building formwork. Thirdly, in the atmosphere, the oxide film on the surface of the magnesium alloy cannot play an effective role in corrosion resistance. So, surface treatment is necessary for magnesium alloy building formwork. Among the various surface treatment methods for magnesium alloys, the chemical conversion method has the advantages of being easy to operate, cost-effective, and having good corrosion resistance. It may be a very suitable protective method for large-scale applications of magnesium alloy building formwork and possesses excellent potential for application. The future of magnesium alloy building formwork will focus on new low-cost materials, high-efficiency processing technology, and low-cost green anti-corrosion technology. With in-depth research and the maturation of technology, magnesium alloy formwork is expected to play a more important role in the construction industry. [ABSTRACT FROM AUTHOR]