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Integrating more active components into a catalyst material could facilitate the development of multifunctional electrocatalysts for energy conversion and storage applications. In this study, we developed a multifunctional electrocatalyst, namely, Pd alloyed with Co-Fe deposited on N-doped mesoporous carbon derived from tissue paper (Pd@Co-Fe/N-TDC). The synergism in Pd@Co-Fe/N-TDC, stemming from the interatomic alloy between Pd and Co-Fe, N-doped mesoporous carbon with defective surfaces, distribution of polyhedral Pd nanoparticles, and strong metal-support interfacial interaction, resulted in significantly high electrocatalytic performance for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Pd@Co-Fe/N-TDC was found to be an efficient bifunctional oxygen electrocatalyst, and this was evidenced by a high onset potential (1.01 V) and kinetic current density (2.6 mA/cm2) for the ORR and by a low overpotential (296 mV) and a low Tafel slope value (38 mV/dec) for the OER, along with a small Δ E of 736 mV. The catalyst also exhibited high durability for both ORR and OER, even after 10000 and 5000 cycles, respectively. Theoretical assessment provides an insight into the synergism of active metal sites in Pd@Co-Fe/N-TDC, which showed its potential for use as a non-Pt electrocatalyst for energy applications. [ABSTRACT FROM AUTHOR]

Despite the attractive combinations of cell/surface interactions, biocompatibility, and good mechanical properties of Ti-6Al-4V, there is still a need to enhance the early stages of cell/surface integration that are associated with the implantation of biomedical devices into the human body. This paper presents a novel, easy and reproducible method of nanoscale and nanostructured hydroxyapatite (HA) coatings on Ti-6Al-4V. The resulting nanoscale coatings/nanostructures are characterized using a combination of Raman spectroscopy, scanning electron microscopy equipped with energy dispersive x-ray spectroscopy. The nanostructured/nanoscale coatings are shown to enhance the early stages of cell spreading and integration of bone cells (hFOB cells) on Ti-6Al-4V surfaces. The improvements include the acceleration of extra-cellular matrix, cell spreading and proliferation by nanoscale HA structures on the coated surfaces. The implications of the results are discussed for the development of HA nanostructures for the improved osseointegration of Ti-6Al-4V in orthopedic and dental applications., (© 2024 Wiley Periodicals LLC.)

In view of a large number of people infected with Helicobacter pylori (H. pylori) with great harm followed, there is an urgent need to develop a non-invasive, easy-to-operate, and rapid detection method, and to identify effective sterilization strategies. In this study, highly specific nanoprobes with nanozyme activity, Ag@Pt nanoparticles (NPs) with the antibody, were utilized as a novel lateral flow immunoassay (LFIA). The optical label (Ag@Pt NPs) was enhanced by the introduction of the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) and compared with a gold nanoparticles (Au NPs) optical label. Under the optimal condition, Ag@Pt-LFIA and TMB-enhanced Ag@Pt-LFIA for H. pylori were successfully established, two of which were over twofold and 100-fold more sensitive than conventional visual Au NP-based LFIA, respectively. Furthermore, Ag@Pt NPs with the antibody irradiated with NIR laser (808 nm) at a power intensity of 550 mW/cm 2 for 5 min exhibited a remarkable antibacterial effect. The nanoprobes could close to bacteria through effective interactions between antibodies and bacteria, thereby benefiting photothermal sterilization. Overall, Ag@Pt NPs provide promising applications in pathogen detection and therapeutic applications., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Biomedical alloys, like many engineering alloys, have chemical or physical heterogeneities at the surface, and such heterogeneities can potentially act as sites for pit initiation. Alloys of particular interest are 316/316L (and 316LVM) stainless steel, nitinol, and CoCr alloys. This review focuses on the sites-generally inclusions-that have been associated with pitting in various studies of biomedical alloys in simulated physiological solutions. The effect of these sites is discussed in relation to factors such as type and size. For both 316/316L stainless steel and nitinol, pitting has been found to initiate at two different types of inclusions: sulfide and oxide inclusions in stainless steel, and carbide and oxide inclusions in nitinol. Sulfide inclusions tend to be the predominant sites for pitting on 316/316L stainless steel, while there is some evidence to suggest that carbide inclusions may be more effective than oxide inclusions for pitting on nitinol. CoCrMo alloys differ from the other two alloys in that, although particles can be present in the form of carbides, the carbides typically do not provide sites for pit initiation except possibly for alloys with a high-C content, certain heat treatments, and when anodically polarized to high potentials. CoNiCrMo differs further in that TiN inclusions can be present in the vicinity of pits and might be associated with them, but irrespective of the initiation site, any pits are unlikely to grow because of repassivation., (© 2023 Wiley Periodicals LLC.)

This response mainly deals with the scientific description of the comments on the structure of the published compound (Bi 1/2 K 1/2)(Fe 1/2 W 1/2)O 3. The newly designed (Bi 1/2 K 1/2)(Fe 1/2 W 1/2)O 3 compound was prepared using the solid-state reaction method. The ingredients were taken to satisfy the required stoichiometry/chemical composition to form a single-phase compound. The lattice parameters and structure is strongly affected by K and W doped elements. The structural analysis is supported by the results of other experimental techniques (dielectric study, Raman characterization, Hysteresis loop, etc.). [ABSTRACT FROM AUTHOR]

According to different smelting processes, nonmetallic inclusions are divided into four grades: basic purity, industrial purity, high purity and ultra‐high purity to cope with the influence of inclusion size and quantity on INVAR foil. Smelting production was carried out according to different needs in OLED field. The concept of "extreme manufacturing" was inducted to design process. The "Four‐Ultra quality" controling that Ultra‐purity, Ultra‐smooth surface, Ultra‐flat shape and Ultra‐precise dimension were put forward and realized in the production process of INVAR alloy foil for FMM. The prepared INVAR alloy foil reached a high level and met the application requirements of FMM. [ABSTRACT FROM AUTHOR]

The article titled "Effect of Final Rolling Temperature on Microstructures and Mechanical Properties of AZ31 Alloy Sheets Prepared by Equal Channel Angular Rolling and Continuous Bending" has been retracted by the journal. The authors raised concerns about redundancy and the improper reuse of figures from one of their previous articles. An investigation confirmed that several figures in the retracted article were duplicated without proper citation or permission. The authors and the journal have decided to retract the article in accordance with the journal's retraction policy. [Extracted from the article]

Purpose: The aviation industry has seen consistent growth over the past few decades. To maintain its sustainability and competitiveness, it is important to have a comprehensive understanding of the environmental impacts across the entire life cycle of the industry, including materials, processes and resources; manufacturing and production; lifetime services; reuse; end-of-life; and recycling. One important component of aircraft engines, integral rotors known as Blisks, are made of high-value metallic alloys that require complex and resource-intensive manufacturing processes. The purpose of this paper is to assess the ecological and economical impacts generated through Blisk production and thereby identify significant 'hot-spots'. Design/methodology/approach: This paper focuses on the methodology and approach for conducting a full-scale Blisk life cycle assessment (LCA) based on ISO 14040/44. Unlike previous papers in the European Aerospace Science Network series, which focused on the first two stages of LCA, this publication delves into the "life cycle impact assessment" and "interpretation" stages, providing an overview of the life cycle inventory modeling, impact category selection and presenting preliminary LCA results for the Blisk manufacturing process chain. Findings: The result shows that the milled titanium Blisk has a lower CO2 footprint than the milled nickel Blisk, which is less than half of the global warming potential (GWP) of the milled nickel Blisk. A main contributor to GWP arises from raw material production. However, no recycling scenarios were included in the analysis, which will be the topic of further investigations. Originality/value: The originality of this work lies in the detailed ecological assessment of the manufacturing for complex engine components and the derivation of hot spots as well as potential improvements in terms of eco-footprint reduction throughout the products cradle-to-gate cycle. The LCA results serve as a basis for future approaches of process chain optimisation, use of "greener" materials and individual process improvements. [ABSTRACT FROM AUTHOR]

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

The welded joints of high/medium entropy alloys (H/MEAs) have shown sound mechanical properties, indicating high promise for the industrial application of this new type of metal alloy. However, these joints possess either relatively low strength or low ductility. In this paper, we used ultrasonic-assisted laser welding to weld CrCoNi MEA with the nitrogen as shielding gas. The results showed that the tensile strength of the joint at room and cryogenic temperature is 686 MPa and 1071 MPa, respectively. The elongation at room and cryogenic temperature is 26.8% and 27.7%, respectively. The combination of the strength and ductility in our joints exceeds that of other welded H/MEA joints. We attributed this excellent combination to the refined dendrite, the solution of nitrogen into the matrix, and the low stacking fault energy of the CrCoNi MEA. The findings in this paper not only provide a novel way to weld H/MEAs with high strength and ductility, also are useful for additively manufacturing the high-performance component of H/MEAs. [ABSTRACT FROM AUTHOR]

In this paper, the precipitation behavior and its effect on resistivity in a new type of nickel–iron-based alloy during short-term aging were investigated. During the aging process, the γ ′ phase increases in average size and decreases in number, with its area fraction fluctuating over time. This fluctuation is caused by the mismatch in the redissolution and growth rates of the γ ′ phase. As the area fraction of the γ ′ phase increases, the content of solute atoms in the matrix that scatter electrons decreases, lowering the resistivity of the alloy. Additionally, the continuous precipitation of M 23 C 6 at grain boundaries during aging causes the resistivity to gradually increase. This paper explains the fluctuation in the total amount of γ ′ phase during short-term aging and proposes a new method for characterizing the precipitation behavior of the γ ′ phase in the novel alloy using the relative trend of resistivity changes. [ABSTRACT FROM AUTHOR]

The study presented in this paper was undertaken in response to two instances of unexpected blade breakage in the cutting blade used in a Carton Wrap machine (CW). Failure of the Al7075 alloy blade occurred at an indentation during typical operational loading conditions. Subsequent metallographic examinations of the fractured samples confirmed that both cases were attributed to fatigue failure. The main objective of this study is to investigate potential causes of fatigue failure in the CW blade using simplified linear elastic static numerical simulations through Finite Element Analysis (FEA). In this research, we employed the well-established Theory of Critical Distance (TCD), and this case study provided a contextualization at an industrial level. Furthermore, the analysis focused on a second key aspect: proposing a new blade geometry aimed at mitigating the identified issues and eliminating possible causes of failure. In this context, the actual stress concentration at the indentation was determined using the TCD with Line Method (LM). The results from the numerical simulations indicated that the new blade geometry significantly reduced stress concentration, resulting in a risk factor reduction of approximately four compared to the original blade design, even under non-optimal operating conditions. Overall, in conjunction with simple linear static FEA, the proposed numerical approach provided substantial support for designers, especially in fault analysis and when comparing different industrial solutions. [ABSTRACT FROM AUTHOR]

The design of efficient and cost-effective electrocatalysts with steady capability has attracted much attention in the field of water splitting in recent years. In this paper, Ni2−xCoxP/CNFs (x = 0, 0.67, 1, 1.33 and 2), where the ultrafine Ni2−xCoxP nanoparticles are encapsulated in carbon nanofibers, are synthesized using a facile electrospinning method followed by thermal treatment. The space confinement by the carbon matrix with a high length-to-diameter ratio (>1000) and excellent conductivity produces ultrafine Ni2−xCoxP with abundant active sites. Moreover, engineering of Ni2−xCoxP/CNFs can induce electronic modulation and consequently optimize the adsorption of H on the electrocatalyst surface to promote HER performance, as well as to reduce the energy barrier of the potential-limiting step. The optimal Ni2−xCoxP/CNFs exhibit superior electrocatalytic performance with low overpotentials of about 271 mV for OER and about 118.76 mV for HER at 10 mA cm−2 with excellent long-term durability in 1.0 M KOH solutions, performing as one of the best non-noble-metal electrocatalysts so far. Furthermore, the two-electrode electrolyser delivers a high efficiency and remarkable long-term durability for overall water splitting. This work provides new insights into the development of nanofiber-structured electrocatalysts. [ABSTRACT FROM AUTHOR]

Rolling is one of the most important processes in the metallurgical industry due to its versatility. Despite its inherent advantages, design and manufacturing by rolling still rely on trial-and-error-based optimizations, which reduces its efficiency. To minimize the cost and time spent on the development of new rolling schedules, various analytical and numerical methods have been used in recent years. Among other alternatives, simulations based on the finite element method (FEM) are the most widely used. This allows for the analysis of the feasibility of new rolling schedules considering metal alloys with different characteristics, process conditions, or the creation of new operations, as well as the optimization of existing ones. This paper presents a literature review including the latest developments in the field of numerical simulation of rolling processes, which have been classified according to the type of rolling into the following categories: flat rolling, shape rolling, ring rolling, cross-wedge rolling, skew rolling, and tube piercing. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (MNPs) composited on metal–organic frameworks (MOFs) can generate valuable materials (MNP/MOF) possessing good physical, chemical, and biological properties. The preparation of novel MNP/MOF followed by exploration of their applications has inspired great investigational enthusiasm. In this paper, Ni, Co and Ni–Co bimetallic MNP/MOF catalysts derived from MOFs were prepared by controlled pyrolysis, and then characterized by TGA, FTIR, XRD, BET, SEM, XPS and H2-TPD, which showed that pyrolysis under H2 (reported typically under an inert atmosphere) and the addition of Co to Ni–MOF could form Ni–Co alloy MOFs with not only a relatively complete MOFs structure but good dispersion of metal nanoparticles. In order to disclose their potential for utilization, specifically, the activity tests of the prepared novel MNP/MOF materials were conducted on the hydrogenation of toluene towards methylcyclohexane. The results confirmed that the Ni1Co2/MOF-325 catalyst obtained by pyrolysis of Ni1Co2–MOF under H2 at 325 °C had high activity and good stability for the hydrogenation of toluene, showing excellent prospect as a hydrogenation catalyst. [ABSTRACT FROM AUTHOR]

Featured Application: This study shows the validation of an effective methodology for determining the residual stresses of components obtained with a 3D-printed polymer such as PLA based on the DIC and the hole-drilling method. The hole-drilling method (HDM) is a common technique used for the determination of residual stresses, especially for metal alloy components, though also for polymers. This technique is usually implemented with strain gages, though other methods for determining the fields of displacements are quite mature, such as the use of digital image correlation (DIC). In the present paper, this combined methodology is applied to a 3D-printed PLA precurved specimen that is flattened in order to impose a bending distribution which can be considered known with a reasonable accuracy. The back-calculated stress distribution is in agreement with the expected (imposed) bending stress, however, a converging iterative procedure for obtaining the solution is introduced and discussed in the paper. [ABSTRACT FROM AUTHOR]

Conventional book casting of Sm2TM17-type alloys (where TM = Co, Fe, Cu, Zr) leads to a coarse, highly segregated microstructure, predominantly due to the slow, variable cooling rate from the mould surface towards the centre of the ingot. These cast alloys require a long homogenisation treatment to remove this segregation and develop a super-saturated, metastable SmTM7-type hexagonal phase. This SmTM7 phase is a vital precursor phase required during magnet production to develop the complex cellular structure responsible for high magnetic properties. In this work, strip casting was employed to facilitate rapid solidification to develop thin flakes (<0.5 mm thick) with a columnar grain structure. Rapid cooling has the potential to produce a homogenous microstructure consisting predominantly of the metastable SmTM7 phase. This could remove or significantly reduce the need for the energy-intensive homogenisation treatment usually required in conventional magnet manufacture. This paper investigates the effect of wheel speed (and hence cooling rate) on flake thickness, microstructure, and phase balance of the cast alloys. It was shown that for wheel speeds between 1.1 and 3.0 m/s, the microstructure showed large variation; however, in all cases, evidence of the columnar SmTM7 phase was presented. The adhesion between the melt and the wheel was deemed to be critical for the nucleation and subsequent columnar growth of SmTM7 grains, where the wheel speed controlled both the flow of the alloy onto the wheel and the thickness of the resultant flake. It was determined that in order to achieve a homogenous columnar SmTM7 structure, the maximum flake thickness should be limited to 270 μm to avoid the formation of equiaxed Sm2TM17 grains through insufficient cooling. [ABSTRACT FROM AUTHOR]

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

A scaffold is a three-dimensional porous structure that is used as a template to provide structural support for cell adhesion and the formation of new cells. Metallic cellular scaffolds are a good choice as a replacement for human bones in orthopaedic implants, which enhances the quality and longevity of human life. In contrast to conventional methods that produce irregular pore distributions, 3D printing, or additive manufacturing, is characterized by high precision and controlled manufacturing processes. AM processes can precisely control the scaffold's porosity, which makes it possible to produce patient specific implants and achieve regular pore distribution. This review paper explores the potential of Ti-6Al-4V scaffolds produced via the SLM method as a bone substitute. A state-of-the-art review on the effect of design parameters, material, and surface modification on biological and mechanical properties is presented. The desired features of the human tibia and femur bones are compared to bulk and porous Ti6Al4V scaffold. Furthermore, the properties of various porous scaffolds with varying unit cell structures and design parameters are compared to find out the designs that can mimic human bone properties. Porosity up to 65% and pore size of 600 μm was found to give optimum trade-off between mechanical and biological properties. Current manufacturing constraints, biocompatibility of Ti-6Al-4V material, influence of various factors on bio-mechanical properties, and complex interrelation between design parameters are discussed herein. Finally, the most appropriate combination of design parameters that offers a good trade-off between mechanical strength and cell ingrowth are summarized., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

With the e-waste growing rapidly all over the globe due to growing demand of electronics, smartphones, etc., coming up with an efficient and sustainable recycling process is the need of the hour. The present work reports a novel and sustainable process of manufacturing Ni alloy by bringing together three major waste streams such as waste Ni-MH batteries, e-waste plastics, and waste glass. The chosen temperature (1550 °C) favours the reduction of nickel-oxide by e-waste plastic as the reductant and sends rare earth elements present in the waste Ni-MH battery as oxide mixture to the slag phase. Waste glass powder used in this process functions as the fluxing agent, hence not requiring any additional flux. The reduction mechanism is gas-based, controlled mainly by hydrogen and carbon monoxide gases released as a result of decomposition of e-waste plastic as reaction commenced from cold zone (∼300 °C) to hot zone (1550 °C) in the horizontal tubular furnace. Formation of nickel alloy and enrichment of slag with mixture of rare earth oxides were confirmed by XRD, SEM-EDS, and Rietveld refining analysis performed on the XRD spectra of slag phase. ICP-OES (Inductively coupled plasma optical emission spectroscopy) and LIBS (laser induced breakdown spectrometer KT-100S) confirmed the high metal content in the alloy, thereby emphasizing the purity (∼98%) which is close to the composition of nickel super alloy. A maximum of 61% by weight REO enrichment was achieved in the slag phase, having La 2 O 3 :44.6%, Pr 2 O 3 :14.8%, and Nd 2 O 3 : 1.6% under optimised experimental conditions (1550 °C, 15 min, and 20% waste glass powder). This scientific investigation evinces a promising route for efficient utilisation of waste streams emanating from e-waste, thereby devising a sustainable recycling technique and protecting the environment, too., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Aluminum‑lithium (AlLi) alloy polishing and grinding processes in wet dust collector systems could cause hydrogen fire and explosion. From the fundamental perspective of preventing hydrogen explosions, a safe, nontoxic, and sustainable modified green hydrogen inhibitor based on chitosan (CS) and sodium alginate (SA) was developed in this study and was used as a hydrogen evolution inhibitor for the processing of waste dust from AlLi alloys. The structure and elemental distribution of the synthesized material were characterized through characterization experiments. Hydrogen evolution experiments and a hydrolysis kinetic model were used to explore the inhibitory effect of modified CS/SA on AlLi alloy dust, and the results revealed that the inhibitory concentration of the hydrogen explosion lower limit was 0.40 wt%, with an inhibition efficiency of 91.93 %, indicating an 11.88-61.44 % improvement over that of CS and SA. As the inhibitor concentration increased and the temperature decreased, the hydrogen inhibition effect increased. Characterization experiments and density functional theory showed that CS/SA primarily formed a dense physical protective barrier on the dust surface through chemical adsorption and complexation reactions, interrupting the hydrogen evolution reaction between the metal and water. This study introduces a novel green modified hydrogen inhibitor that fundamentally addresses hydrogen generation and explosion., Competing Interests: Declaration of competing interest We declare that we have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Additive manufacturing (AM) of Ti-based biomedical implants is a pivotal research topic because of its ability to produce implants with complicated geometries. Despite desirable mechanical properties and biocompatibility of Ti alloys, one major drawback is their lack of inherent antibacterial properties, increasing the risk of postoperative infections. Hence, this research focuses on the Ti536 (Ti5Al3V6Cu) alloy, developed through Electron Beam Powder Bed Fusion (EB-PBF), exploring bio-corrosion, antibacterial features, and cell biocompatibility. The microstructural characterization revealed grain refinement and the formation of Ti 2 Cu precipitates with different morphologies and sizes in the Ti matrix. Electrochemical tests showed that Cu content minimally influenced the corrosion current density, while it slightly affected the stability, defect density, and chemical composition of the passive film. According to the findings, the Ti536 alloy demonstrated enhanced antibacterial properties without compromising its cell biocompatibility and corrosion behavior, thanks to Ti 2 Cu precipitates. This can be attributed to both the release of Cu ions and the Ti 2 Cu precipitates. The current study suggests that the EB-PBF fabricated Ti536 sample is well-suited for use in load-bearing applications within the medical industry. This research also offers an alloy design roadmap for novel biomedical Ti-based alloys with superior biological performance using AM methods., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Although magnesium alloy has received tremendous attention in biodegradable cardiovascular stents, the poor in vivo corrosion resistance and limited endothelialization are still the bottlenecks for its application in cardiovascular stents. Fabrication of the multifunctional bioactive coating with excellent anti-corrosion on the surface is beneficial for rapid re-endothelialization and the normal physiological function recovery of blood vessels. In the present study, a bioactive hydrogel coating was established on the surface of magnesium alloy by copolymerization of sulfobetaine methacrylate (SBMA) and acrylamide (AM) via ultraviolet (UV) polymerization, followed by the immobilization of fucoidan (Fu). The results showed that the as-prepared multifunctional hydrogel coating could enhance the corrosion resistance and the surface wettability of the magnesium alloy surface, endowing it with the ability of selective albumin adsorption; meanwhile, it could augment biocompatibility. The following introduction of fucoidan on the surface could further improve the hemocompatibility characterized by reducing protein adsorption, minimizing hemolysis, and preventing platelet aggregation and activation. Additionally, the immobilized fucoidan promoted endothelial cell (EC) growth, as well as up-regulated the expression of vascular endothelial growth factor (VEGF) and nitric oxide (NO) in endothelial cells (ECs). Consequently, this research paves a novel approach to developing a versatile bioactive coating for magnesium alloy surfaces and lays a foundation in cardiovascular biomaterials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this study, the interaction of pure Mg and WE43 alloy under the presence of osteoblast (OB) and osteoclast (OC) cells and their influence on the degradation of materials have been deeply analyzed. Since OB and OC interaction has an important role in bone remodeling, we examined the surface morphology and dynamic changes in the chemical composition and thickness of the corrosion layers formed on pure Mg and WE43 alloy by direct monoculture and coculture of pre-differentiated OB and OC cells in vitro. Electrochemical techniques examined the corrosion performance. The corrosion products were characterized using a combination of the focused ion beam (FIB), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). Cell viability and morphology were assessed by fluorescent microscopy and SEM. Our findings demonstrate cell spread and attachment variations, which differ depending on the Mg substrates. It was clearly shown that cell culture groups delayed degradation processes with the lowest corrosion rate observed in the presence of OBOC coculture for the WE43 substrate. Ca-P enrichment was observed in the outer-middle region of the corrosion layer but only after 7 days of OBOC coculture on WE43 and after 14 days on the pure Mg specimens. STATEMENT OF SIGNIFICANCE: Magnesium metallic materials that can degrade over time provide distinct opportunities for orthopedic application. However, there is still a lack, especially in elucidating cell-material interface characterization. This study investigated the influence of osteoblast-osteoclast coculture in direct Mg-material contact. Our findings demonstrated that pre-differentiated osteoblasts and osteoclasts cocultured on Mg substrates influenced the chemistry of the corrosion layers. The cell spread and attachment were Mg substrate-dependent. The findings of coculturing bone cells directly on Mg materials within an in vitro model provide an effective approach for studying the dynamic degradation processes of Mg alloys while also elucidating cell behavior and their potential contribution to the degradation of these alloys., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The present study adopts a multi-facet approach to design bio inspired concentrated alloys for potential application as articulating surfaces in joint replacements. A series of equiatomic, Nb rich and Ti rich TiMoNbZr based medium entropy alloys (MEAs) were processed via arc melting and their mechanical, in-vitro corrosion, wear, and in vitro and in vivo biocompatibility were investigated. Equiatomic MEA had primarily bcc with minor hcp phases where the single bcc was achieved with the addition of Nb. The single bcc Nb rich alloy resulted in 13 % elongation, much higher than equiatomic or Ti rich alloy. All the MEAs showed comparatively higher yield strength due to the climb of edge dislocations which is the main rate limiting mechanism at 300 K, as evident molecular dynamics (MD) simulation. The locally fluctuating energy landscape promotes kinks on edge dislocation, and at local minima nanoscale segments gets pinned. Upon yielding the entangled kink leaves a trail of vacancies/interstitials and escapes via climb motion to render high yield strength. The higher corrosion and pitting resistance of Nb enriched alloys can be attributed to the stable ZrO 2 , Nb 2 O 5 , TiO 2 , and MoO 3 oxides, high polarization resistance (10 6 -10 5 Ωcm -2 ), and low defect densities (10 16 -10 18 ). In vitro cell-materials interaction using MC3T3-E1 showed bioinert but cytocompatible nature of the MEAs. The wear rate of the MEAs was in the range of 7-9 × 10 -5 mm 3 N -1 m -1 . The wear debris did not show any tissue necrosis when implanted in rabbit femur rather new bone regeneration can be seen around the particles. STATEMENT OF SIGNIFICANCE: In the present work, a noble Nb enriched MEAs with superior mechanical, in vitro wear, corrosion and cytocompatibility properties was designed for articulating surfaces in joint replacement., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

This study evaluated the effect of solvent acids on the structure and corrosion resistance performance of chitosan (CS) film on MAO-treated AZ31B magnesium (Mg) alloy. Initially, CS solutions were prepared in four solvent acids: acetic acid (HAc), lactic acid (LA), hydrochloric acid (HCl), and citric acid (CA). The CS films were subsequently deposited on MAO-treated AZ31B Mg alloy via a dip-coating technique. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD), Fourier-transform infrared spectroscopy (FT-IR), contact angle measurement, and atomic force microscopy (AFM) were employed to characterize the surface and cross-sectional morphology as well as chemical composition. Furthermore, the samples were subjected to potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) tests to assess their resistance against corrosion in simulated body fluid (SBF). These results indicated that the CS film prepared with LA exhibited the lowest surface roughness (R a  = 31.2 nm), the largest contact angle (CA = 98.50°), and the thickest coating (36 μm). Additionally, it demonstrated superior corrosion protection performance, with the lowest corrosion current density (I corr  = 3.343 × 10 -7 A/cm 2 ), highest corrosion potential (E corr  = -1.49 V), and highest polarization resistance (R p  = 5.914 × 10 4  Ω·cm 2 ) in SBF. These results indicated that solvent acid types significantly influenced their interactions with CS. Thus, the structure and corrosion protection performance of CS films can be optimized by selecting an appropriate solvent acid., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Bone defects, resulting from trauma, inflammation, tumors, and various other factors, affect both health and quality of life. Although autologous bone transplantation is the gold-standard treatment for bone defects, it has disadvantages such as donor site limitations, prolonged surgical durations, and potential complications, necessitating the development of alternative bone tissue engineering materials. In this study, we used 3D printing technology to fabricate porous titanium implants characterized by superior biocompatibility and mechanical properties. Sodium alginate (SA) and strontium ions (Sr 2+ ) were integrated into mineralized collagen matrices (MCs) to develop strontium-functionalized alginate-mineralized collagen hydrogels (SAMs) with high mechanical strength and sustained metal ion release ability. SAMs were seamlessly incorporated into the porous structures of 3D-printed titanium scaffolds, establishing a novel organic-inorganic bioactive interface. This composite system exhibited high biocompatibility in vitro and increased the expression of genes important for osteogenic differentiation and angiogenesis. In a rabbit model of femoral defect, the titanium implants effectively promoted bone and vascular regeneration on their surface, highlighting their potential in facilitating bone-implant integration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Biodegradable zinc (Zn) alloys stand out as promising contenders for biomedical applications due to their favorable mechanical properties and appropriate degradation rates, offering the potential to mitigate the risks and expenses associated with secondary surgeries. While current research predominantly centers on the in vitro examination of Zn alloys, notable disparities often emerge between in vivo and in vitro findings. Consequently, conducting in vivo investigations on Zn alloys holds paramount significance in advancing their clinical application. Different element compositions and processing methods decide the mechanical properties and biological performance of Zn alloys, thus affecting their suitability for specific medical applications. This paper presents a comprehensive overview of recent strides in the development of biodegradable Zn alloys, with a focus on key aspects such as mechanical properties, toxicity, animal experiments, biological properties, and molecular mechanisms. By summarizing these advancements, the paper aims to broaden the scope of research directions and enhance the understanding of the clinical applications of biodegradable Zn alloys.

Metals are widely utilized as implant materials for bone fixtures as well as stents. Biodegradable versions of these implants are highly desirable since patients do not have to undergo a second surgery for the materials to be removed. Attractive options for such materials are zinc silver alloys since they also offer the benefit of being antibacterial. However, it is important to investigate the effect of the degradation products of such alloys on the surrounding cells, taking into account silver cytotoxicity. Here we investigated zinc alloyed with 1 % of silver (Zn1Ag) and how differently concentrated extracts (1 %-100 %) of this material impact human umbilical vein endothelial cells (HUVECs). More specifically, we focused on free radical generation and oxidative stress as well as the impact on cell viability. To determine free radical production we used diamond-based quantum sensing as well as conventional fluorescent assays. The viability was assessed by observing cell morphology and the metabolic activity via the MTT assay. We found that 1 % and 10 % extracts are well tolerated by the cells. However, at higher extract concentrations we observed severe impact on cell viability and oxidative stress. We were also able to show that quantum sensing was able to detect significant free radical generation even at the lowest tested concentrations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Although titanium alloy is the most widely used endoplant material in orthopedics, the material is bioinert and good bone integration is difficult to achieve. Zoledronic acid (ZOL) has been shown to locally inhibit osteoclast formation and prevent osteoporosis, but excessive concentrations of ZOL exert an inhibitory effect on osteoblasts; therefore, stable and controlled local release of ZOL may reshape bone balance and promote bone regeneration. To promote the adhesion of osteoblasts to many polar groups, researchers have applied gelatine methacryloyl (Gelma) combined with polyacrylamide hydrogel (PAAM), which significantly increased the hydrogen bonding force between the samples and improved the stability of the coating and drug release. A series of experiments demonstrated that the Gelma/PAAM-ZOL bioactive coating on the surface of the titanium alloy was successfully prepared. The coating can induce osteoclast apoptosis, promote osteoblast proliferation and differentiation, achieve dual regulation of bone regeneration, successfully disrupt the balance of bone remodelling and promote bone tissue regeneration. Additionally, the coating improves the metal biological inertness on the surface of titanium alloys and improves the bone integration of the scaffold, offering a new strategy for bone tissue engineering to promote bone technology., Competing Interests: Declaration of competing interest All authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Biodegradable Zn alloys have significant application potential for hard-tissue implantation devices owing to their suitable degradation behavior and favorable biocompatibility. Nonetheless, pure Zn and its alloys in the as-cast state are mechanically instable and low in strength, which restricts their clinical applicability. Here, we report the exceptional mechanical, corrosion, and biocompatibility properties of hot-extruded Zn-5RE (wt.%, RE = rare earth of Y; or Ho; or Er) alloys intended for use in biodegradable bone substitutes. The microstructural characteristics, mechanical behavior, corrosion resistance, cytocompatibility, osteogenic differentiation, and capacity of osteogenesis in vivo of the Zn-5RE alloys are comparatively investigated. The Zn-5Y alloy demonstrates the best tensile properties, encompassing a 138 MPa tensile yield strength, a 302 MPa ultimate tensile strength, and 63% elongation, while the Zn-5Ho alloy shows the highest compression yield strength of 260 MPa and Vickers hardness of 104 HV. The Zn-5Er alloy shows a 126 MPa tensile yield strength, a 279 MPa ultimate tensile strength, 52% elongation, a 196 MPa compression yield strength, and a 101 HV Vickers microhardness. Further, the Zn-5Er alloy has a 130 µm per year corrosion rate in electrochemical tests and a 26 µm per year degradation rate in immersion tests, which is the lowest among the tested alloys. It also has the best in vitro osteogenic differentiation ability and capacity for osteogenesis and osteointegration in vivo after implantation in rat femurs among the Zn-5RE alloys, indicating promising potential in load-bearing biodegradable internal bone-fixation applications. STATEMENT OF SIGNIFICANCE: This work reports the exceptional mechanical, corrosion, and biocompatibility properties of hot-extruded (HE) Zn-5 wt.%-rare earth (Zn-5RE) alloys using single yttrium (Y), holmium (Ho), and erbium (Er) alloying for biodegradable bone-implant applications. Our findings demonstrate that the HE Zn-5Er alloy showed σ uts of 279 MPa, tensile yield strength of 126 MPa, elongation of 51.6%, compression yield strength of 196 MPa, and microhardness of 101.2 HV. Further, HE Zn-5Er showed the lowest electrochemical corrosion rate of 130 µm/y and lowest degradation rate of 26 µm/y, and the highest in vitro osteogenic differentiation ability, in vivo osteogenesis, and osteointegration ability after implantation in rat femurs among the Zn-5RE alloys, indicating promising potential in load-bearing biodegradable internal bone-fixation applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Developing new low modulus structures is important for reducing the risk of aseptic loosening during loading of implant materials. However, an alloy that may also confer some advantage at preventing septic loosening could dramatically improve the outcomes for patients. Nevertheless, the predictive power of current models remains limited to common alloying additions. As such, this study considers the mechanical properties of a range of Ti-Nb-Au superelastic alloys to elucidate the composition range for which low modulus structures can be achieved. These modulus values are compared to other critical design parameters such as strain recovery and strength. It was found that Au additions are effective at suppressing the formation of the ω phase and allow alloys with lower moduli to be achieved. It was also shown that low β phase stability is critical for achieving the lowest modulus, and that this susceptibility to transform to a martensite may enable higher strengths to be achieved. However, this low β phase stability also limits the strain recovery that may be achieved meaning these two properties are not necessarily independently tuneable. These data provide important context for the design of new systems containing unusual alloying additions such as Au., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The Ti6Al4V (TC4) alloy, a prevalent biomedical material in orthopedics, still faces limitation of the insufficient osseointegration. To improve the bioactivity of TC4, introducing the electric environment onto the TC4 surface may be an effective way in the view of the necessity of endogenous electric microenvironment in bone regeneration. Herein, a Volta potential pattern was engendered on the TC4 surface via parallel laser patterning, so as to promote the osteogenic differentiation of cells. A 15 W laser successfully transformed the original α + β dual phase towards radially distributed lath-like martensite phase in the laser treated region. The atomic lattice distortion between the heterogeneous microstructures of the laser treated and untreated regions leads to a significant Volta potential fluctuation on the TC4 surface. The Volta potential pattern as well as the laser-engraved microgrooves respectively induced mutually orthogonal cell alignments. The hBMSCs osteogenic differentiation was significantly enhanced on the laser treated TC4 surfaces in comparison to the surface without the laser treatment. Moreover, a drastic Volta potential gradient on the TC4 surface (treated with 15 W power and 400 μm interval) resulted in the most pronounced osteogenic differentiation tendency compared to other groups. Modulating the electric environment on the TC4 surface by manipulating the phase transformation may provide an effective way in evoking favorable cell response of bone regeneration, thereby improving the bioactivity of TC4 implant., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Peri-implantitis and insufficient osseointegration are the principal challenges faced by dental implants at present. In order to fabricate dual-function dental implant materials possessing both antibacterial and osteogenic capabilities, this study incorporates the antimicrobial element Cu into the Ti40Nb alloy, developing a novel Ti40Nb-xCu alloy with antibacterial properties. Among them, Ti40Nb3Cu has the best overall performance. Compared to Ti40Nb, the tensile strength increased by 27.97%, reaching 613 MPa. Although the elongation rate has decreased from 23% to 13.5%, the antibacterial rates against S. aureus and P. gingivalis both exceed 85%. Furthermore, the surface of Ti40Nb-xCu alloy was then treated with micro-arc oxidation to enhance its bioactivity, thereby accelerating osseointegration. The results indicated that the MAO treatment retains the antibacterial properties of the Ti40Nb3Cu alloy while significantly promoting bone formation through its introduced porous coating, thus heralding it as a propitious candidate material for dental implant applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

In this paper, magnetic nanopowders of Fe 19.5 Ni 40 Co 19.5 Cr 19.5 Y 1.5 high-entropy alloy compositions were successfully prepared by the liquid phase reduction method, which represented a breakthrough from the traditional process of preparing high-entropy alloy nanopowders. The powders had a high specific surface area of 136.23 m 2 /g and exhibited sustained, efficient, and rapid degradation characteristics for high concentrations of CR and ultra-high concentrations of Cr(VI) wastewater. It was demonstrated that the removal rate of CR remained at 100 % after 100 cycles and 81 % of Cr after 8 cycles of the powder without changing the pH and room temperature. The powders also demonstrated good soft magnetic properties, which allowed them to be conveniently separated and recycled using magnetic field treatment, thus addressing the issue of recycling raw materials without causing secondary pollution in wastewater treatment. Furthermore, the analyzed powders also exhibited fast and efficient degradation effects., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

After total hip arthroplasty, the stress shielding effect can occur due to the difference of stiffness between the metallic alloy of the stems and the host bone, which may cause a proximal bone loss. To overcome this problem, a low-modulus metastable β Ti-20Zr-3Mo-3Sn alloy composition has recently been designed to be potentially used for the cementless femoral hip stems. After having verified experimentally that the β alloy has a low modulus of around 50 GPa, a finite element analysis was performed on a Ti-20Zr-3Mo-3Sn alloy hip prosthesis model to evaluate the influence of a reduced modulus on stress shielding and stress fields in both stem and bone compared with the medical grade Ti-6Al-4V alloy whose elastic modulus reached 110 GPa. Our results show that the Ti-20Zr-3Mo-3Sn stem with low elastic modulus can effectively reduce the total stress shielding by 45.5% compared to the common Ti-6Al-4V prosthesis. Moreover, it is highlighted that the material elasticity affects the stress distribution in the implant, especially near the bone-stem interfaces., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

MgGa alloys are considered highly potential biodegradable materials, owing to its good mechanical properties and appropriate corrosion resistance. However, it is still far from application due to the lack of biological evaluation. In the present study, biocompatibility, osteogenesis and antibacterial activity of extruded Mg-xGa (x = 1 and 5 wt%) alloys were investigated by in vitro cell culture experiments and in vivo implantation. The cell adhesion and proliferation of osteoblast precursor cells (MC3T3-E1) showed the excellent cytocompatibility of Mg-1Ga and poor cytocompatibility of Mg-5Ga. The osteogenic activity was evaluated and revealed that Ga 3+ in the Mg-1Ga extract had the ability to enhance osteogenic differentiation through the facilitation of its early stages. In vivo studies in a rat femoral condyle model revealed that both Mg-1Ga and Mg-5Ga significantly promoted new bone formation without causing any adverse effects. Mg-5Ga exhibited a much higher corrosion rate in vivo than Mg-1Ga. Its osteogenic activity was better due to the rapid release of Mg 2+ and Ga 3+ , but this caused premature structural integrity loss. Mg-1Ga and Mg-5Ga released Ga 3+ to inhibit E. coli and S. aureus, with antibacterial rate increasing with Ga content. Our studies demonstrate that Mg-Ga alloys have the potential to be used as osteogenic and antibacterial implant materials. STATEMENT OF SIGNIFICANCE: This study evaluates the biocompatibility, osteogenesis, and antibacterial activity of Mg-Ga alloys, which are promising biodegradable materials for medical applications. The study finds that Mg-1Ga exhibits excellent cytocompatibility and promotes osteogenic differentiation, facilitating the early stages of osteoblast precursor cell development. In vivo studies in a rat femoral condyle model reveal that Mg-1Ga and Mg-5Ga significantly promote new bone formation without causing any adverse effects. The antibacterial activity of both alloys is evaluated against E. coli and S. aureus, with the inhibition rate increasing with Ga content. These findings suggest that Mg-Ga alloys have the potential to serve as osteogenic and antibacterial implant materials, providing significant insights into the development of novel biomedical implants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

In this paper, the Ti6Al4V alloy surface was modified via ceramic conversion treatment (CCT) with or without a pre-deposited silver layer. After characterizing the surface morphologies, microstructure and phase constituents of the ceramic oxide layer formed at 620 °C, we investigated the surface hardness and the cross-sectional nano-hardness profile under the oxide layer. The static load-bearing capacity of the oxide layers was examined by applying discrete loads via a Vickers indenter and observing the indentations. A scratch test was used to evaluate the load-bearing capacity and the adhesion/cohesion of the oxide layers. The wettability of the surface changed due to the incorporation of silver and the change of surface morphology. Reciprocating friction and wear test was used to assess the tribological properties. Small and dispersed silver nanoparticles and clusters were found in the oxide layer of the Ag pre-deposited Ti6Al4V samples, and they had much better tribological properties in terms of reduced coefficient of friction and wear volume. With the assistance of silver, the efficiency of the CCT was significantly improved., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2024. Published by Elsevier Ltd.)

This paper deals with the combined effects of immune response and osseointegration because of the lack of comprehensive studies on this topic. An antibacterial Ti surface was considered because of the high risk of infection for titanium bone implants. A chemically treated Ti6Al4 V alloy [Ti64(Sr-Ag)] with a microporous and Sr-Ag doped surface was compared to a polished version (Ti64) regarding protein adsorption (albumin and fibronectin) and osteoimmunomodulation. Characterization via fluorescence microscopy and zeta potential showed a continuous fibronectin layer on Ti64(Sr-Ag), even with preadsorbed albumin, while it remained filamentous on Ti64. Macrophages (differentiated from THP-1 monocytes) were cultured on both surfaces, with viability and cytokine release analyzed. Differently from Ti64, Ti64(Sr-Ag) promoted early anti-inflammatory responses and significant downregulation of VEGF. Ti64(Sr-Ag) also enhanced human bone marrow mesenchymal cell differentiation toward osteoblasts, when a macrophage-conditioned medium was used, influencing ALP production. Surface properties in relation to protein adsorption and osteoimmunomodulation were discussed.

Cerium (Ce) are the most widely distributed rare earth element. However, humans exposed to Ce through inhalation have been reported to experience heat sensitivity, itching, and heightened taste and odour perception. The present study aims to develop an optical sensor device with a short response time and high selectivity for Ce amongst other ions in various environments. The potential applicability of a 6-hydroxy-5-((4-hydroxy-2-methylphenyl)diazenyl)pyrimidine-2,4(1H,3H)-dione (HHMDPD) assembled ligand as aceric ion (Ce 4+ )-selective caption optode was examined. After generating an ion pair with Tetra-n-octylammonium bromide (TOABr) and immobilizing on a tri-acetyl cellulose (TAC) membrane, the solubility of the HHMDPD ligand is improved. The constructed optode membrane reacts with Ce 4+ by turning its orange colour to violet in Thiel buffer (pH of 5.5), which can be detected spectrophotometrically at λ max 667 nm. The measurement linearity was in the range of 0.70 - 18.7 × 10 -6 mol/L of Ce 4+ concentration with detection and quantification limits of 0.23 × 10 -6 and 0.70 × 10 -6 mol/L, respectively. Whatever the Ce 4+ concentration in its real samples, the response time of the constructed device was 5.0 min. Additionally, it recorded repeatability and reproducibility with a %RSD of 1.37 and 2.55, respectively (n = 3). The proposed optode device exhibited complete reversibility, for multiple measurements, which could be easily achieved with the aid of a solution of HCl, 0.01 mol/L. The applicability of the proposed device has been effectively extended to analyze synthetic mixes corresponding to different Ce 4+ real human, foods, water, and magnesium-based Ce 4+ alloys., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The aim of this study is to compare the stress distribution in porous scaffolds with different structures with similar geometric parameters to study a new approach in dental implantation. Three-dimensional finite element models of the fully porous and dense-core porous scaffolds with defined porosity parameters including space diameter and thickness with two porosity patterns were embedded in the jaw bone model with cortical and cancellous bone. The cylindrical shape was considered as the main shape of the scaffolds. To evaluate the mechanical performance, the Von Mises stress was compared in the models under static and dynamic masticatory loading. Incidentally, to validate the modeling results, experimental strain gauge tests were performed on four specimens fabricated from Ti6Al4V. Finally, the stress distribution in the models was compared with the results of previous studies on commercial implants. The results of the finite element analysis show that there are considerable differences in the magnitude of the equivalent stress in the models in static and dynamic phases. Also, changes in the defined geometric parameters have significant effects on the stress distribution in terms of Von Mises stress in the overall models. The experimental results indicated good agreement with those of the modeling. It can be concluded that some porous structures with optimal geometries can be proposed as a new structure for dental implants. However, considering the physiology of bone when confronted with porous structures, further studies such as in vivo experiments are needed in this field., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Metallic biomaterials, such as stainless steels, cobalt-chromium-molybdenum (Co-Cr-Mo) alloys, and titanium (Ti) alloys, have long been used as load-bearing implant materials due to their metallic mechanical strength, corrosion resistance, and biocompatibility. However, their magnetic susceptibility and elastic modulus of more than 100 GPa significantly restrict their therapeutic applicability. In this study, spinodal Zr 60 Nb 40 , Zr 50 Nb 50 , and Zr 40 Nb 60 (at.%) alloys were selected from the miscibility gap based on the Zr-Nb binary phase diagram and prepared by casting, cold rolling, and aging. Their microstructure, mechanical properties, corrosion resistance, magnetic susceptibility, and biocompatibility were systematically evaluated. Spinodal decomposition to alternating nanoscale Zr-rich β 1 and Nb-rich β 2 phases occurred in the cold-rolled Zr-Nb alloys during aging treatment at 650 °C. In addition, a minor amount of α phase was precipitated in Zr 60 Nb 40 due to the thermodynamic instability of the Zr-rich β 1 phase. Spinodal decomposition significantly improved the mechanical strength of the alloys due to nanosized dual-cubic reinforcement. The Zr-Nb alloys showed an electrochemical corrosion rate of 94-262 nm per year in Hanks' solution because of formation of dense passive films composed of ZrO 2 and Nb 2 O 5 during the polarization process. The magnetic susceptibilities of the Zr-Nb alloys were significantly lower than those of commercial Co-Cr-Mo and Ti alloys. The cell viability of the Zr-Nb alloys was more than 98 % toward MC3T3-E1 cells. Overall, the spinodal Zr-Nb alloys have enormous potential as bone-implant materials due to their outstanding overall mechanical properties, extraordinary corrosion resistance, low magnetic susceptibility, and sufficient bicompatibility. STATEMENT OF SIGNIFICANCE: This work reports on spinodal Zr-Nb alloys with heterostructure. Spinodal decomposition significantly improved their mechanical strength due to the nanosized dual-cubic reinforcement. The Zr-Nb alloys showed large corrosion resistance in Hanks' solution because of formation of dense passivation films composed of ZrO 2 and Nb 2 O 5 during the polarization process. The magnetic susceptibilities of the Zr-Nb alloys were significantly lower than those of commercial Co-Cr-Mo and Ti alloys. The cell viability of the Zr-Nb alloys was more than 98 % toward MC3T3-E1 cells. The results demonstrate that spinodal Zr-Nb alloys have enormous potential as bone-implant materials due to their outstanding overall mechanical properties, high corrosion resistance, low magnetic susceptibility, and sufficient biocompatibility., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Magnesium (Mg) and its alloys were favored by biomedical practitioners thanks to availability of bioactivity and degradability. However, the mismatch between the degradation properties of Mg alloys and the rate of osteogenesis often led to implant failure and bacterial infections within the desired period. The goal of this study was to improve the corrosion resistance of Mg alloys, providing theoretical guidance for solving the problems of implantable Mg-based materials. In this experiment, we prepared a dense and uniform BTESPT/TiO 2 film layer on the surface of Mg substrate by electrochemically assisted deposition. The BTESPT/TiO 2 film layer provided a physical barrier to avoid direct contact between AZ31 and the corrosive medium. When the addition amount was 2 g/L TiO 2 , the coating had the best corrosion resistance behavior, its corrosion current density could be up to 9.973×10 -8 A/cm 2 . The BTESPT/TiO 2 revealed good cell viability as well as osteogenic differentiation potential on MC3T3-E1 cells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The magnetic characteristics of Fe-based nanocrystalline alloys can be influenced by temperature. The conventional dynamic Jiles–Atherton (J-A) hysteresis model does not take into consideration the impact that temperature has on magnetic characteristics. A novel variable-temperature dynamic J-A hysteresis model is proposed in this paper to effectively address the issue. Firstly, the hysteresis loops of Fe-based nanocrystalline are measured at −50 °C–130 °C and DC state. The five parameters of the J-A hysteresis model are identified at various temperatures using the particle swarm optimization algorithm, and five parameters are fitted as functions of temperature. Subsequently, the five parameters as functions of temperature are introduced into the conventional dynamic J-A hysteresis model to construct a novel variable-temperature dynamic J-A hysteresis model, which can not only reflect the impact of temperature but also accurately calculate the losses. Finally, hysteresis loops and losses of Fe-based nanocrystalline alloy are simulated and calculated at different temperatures and frequencies by the variable-temperature dynamic J-A hysteresis model. Meanwhile, this paper also investigates the trends and percentages of hysteresis loss, excess loss as well as eddy current loss with frequency and temperature. Compared to the results of measured data, the maximum average error of the variable-temperature dynamic J-A hysteresis model is 5.83%. [ABSTRACT FROM AUTHOR]

In the automobile, aerospace and other sectors, the use of titanium has enabled several types of applications. Understanding its fundamentals is necessary not only to identify the corrosion mechanisms, but also to prevent it through appropriate protection techniques and to predict the behavior of corrosion in metallic materials under service conditions. Understanding corrosion mechanisms is a key to develop a knowledge-based design of corrosion-resistant alloys and predicting the long-term behavior of metallic materials in corrosive environments. This paper analyzes the corrosion resistance of metallic alloys Ti6Al4V and CoCrMo when immersed in electrolytic solutions. In addition, this paper studies the possible corrosion effects caused by temperature, pH and immersion time conditions and carry out electrochemical tests such as: OCP; ECIS and polarization curve. From the obtained data, observe the behavior of Ti6Al4V and CoCrMo alloys. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to comprehensively review the preparation methods of superhydrophobic surfaces (SHPS) for corrosion protection of Mg alloy in recent years. Design/methodology/approach: The preparation methods, wettability and corrosion resistance of SHPS on Mg alloy in the past three years are systematically described in this paper. Findings: Two types of SHPS, including single-layer and multilayer coatings for corrosion protection of Mg alloy are summarized. Preparing multilayered coatings with multifunction is the current trend in developing SHPS on Mg alloy. Originality/value: This paper reviewed the preparation methods and corrosion resistance of SHPS on Mg alloys. It provides a valuable reference for researchers to develop highly durable SHPS with excellent corrosion resistance for Mg alloys. [ABSTRACT FROM AUTHOR]