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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]

Activating flux is made up of inorganic material mixed with a volatile medium. The objective of this study is to identify and review the literature in activating flux, and different type of welding techniques. For that purpose, a structured review method is adopted and the Scopus database is used as a primary source for the selection of papers. The papers were identified using the string term of “Activating flux” OR “Activated flux” in the title of papers. And a total of 238 papers were identified for the study. Besides the above few other papers were also reviewed and the materials used, the type of flux used, and the findings of different combinations were highlighted in the form of tables. The findings of the study provide a comprehensive understanding of the different type of welding techniques focusing on TIG welding, and the different combination of flux used and their impact was summarized.

Activating flux is made up of inorganic material mixed with a volatile medium. The objective of this study is to identify and review the literature in activating flux, and different type of welding techniques. For that purpose, a structured review method is adopted and the Scopus database is used as a primary source for the selection of papers. The papers were identified using the string term of "Activating flux" OR "Activated flux" in the title of papers. And a total of 238 papers were identified for the study. Besides the above few other papers were also reviewed and the materials used, the type of flux used, and the findings of different combinations were highlighted in the form of tables. The findings of the study provide a comprehensive understanding of the different type of welding techniques focusing on TIG welding, and the different combination of flux used and their impact was summarized. [ABSTRACT FROM AUTHOR]

The history of antimony modification of Al–Si casting alloys is reviewed, together with the important technical and commercial reasons why antimony is no longer used as a modifier. [ABSTRACT FROM AUTHOR]

Facile fabrication of flexible substrates containing high concentration of nanoparticles (NPs) is very promising owing to their capability of swab-based surface-enhanced Raman scattering (SERS) trace detection. However, the background signal of the substrate could compromise the trace-detection capabilities. Moreover, the presence of fluorescent molecules may result in intense fluorescence background which could overshadow the Raman peaks. Herein, we demonstrate that the surfactant-free bimetallic (Ag and Au) NPs, synthesized directly on the filter paper, are very effective in reducing the background signal in SERS-based trace detection. Simple soaking of filter paper in a mixture of HAuCl 4 and AgNO 3 solution, and its immediate drying and reduction produces Au-Ag alloy NPs on the filter paper. Interestingly, the substrates are very effective in quenching the background fluorescence of both filter paper and the analyte, thereby effectively detecting the SERS signature of the fluorescent molecules. In particular, Rhodamine6G (R6G) concentrations down to 10−10 M were detected under resonance excitation, both by solution drying and swabbing. The swab detection of ammonium nitrate, which is usually used in homemade explosives, was also demonstrated. Moreover, owing to the fluorescence quenching properties, the Au-Ag alloy substrates (AuAgS) were able to carry out the swab-based multiplex-detection of crystal violet (CV), Brilliant Cresyl Blue (BCB), and R6G upon resonance excitation of R6G. Finally, the substrates have shown good reproducibility, stability, and signal uniformity. This verifies the potential of AuAgS for real-world trace-detection applications. [ABSTRACT FROM AUTHOR]

A Ru-Ni@Cu alloy catalyst with a well-connected two-phase or three-phase contact interface is fabricated as an alternative to a Pt-based catalyst for the hydrogen evolution reaction (HER) in water electrolysis in this study. For optimum bonding and adhesion stability, the alloy particles are grown directly on carbon paper (CP) by the hydrothermal method. The alloy particles are composed of central Cu cores, Ni nests wrapped around Cu core, and small (2.0 nm) Ru nanoparticles embedded at the Ni nests. The Ni surface readily adsorbs water, the high conductivity of Cu increases the electron density of the electrode surface to facilitate water splitting, and the Ru surface adsorbs more H+ ions, thus promoting hydrogen production in the Ru-Ni@Cu alloy. Eventually, despite the use of only 1.0 wt% Ru, the 1% Ru-Ni@Cu/CP electrode exhibits a low overpotential of −0.15 V (η = 246 mV and 87.08 mV dec−1) at 100 mA cm−2 in a 1.0 M KOH electrolyte, similarly to the −0.1 V overpotential of the 100% Pt/CP electrode. The electrode maintains excellent catalytic activity without deterioration for 10 days with a Faraday efficiency of 96.89% (50 h) HER and 3000th LSV cycles. [Display omitted] • Ru-Ni@Cu alloy with three-phase interface grown directly onto CP. • Cu core in the center, Ni nest on the outside, and 2.0 nm-sized Ru particle between Cu and Ni. • Hydrogen production promoted by more H+ ions adsorption on the Ru surface. • A low overpotential of −0.15 V even though only 1.0 wt.-% Ru usage. • Faraday efficiency of 96.89% for 3000 min-HER, without catalytic deactivation for 10 days. [ABSTRACT FROM AUTHOR]

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]

Nanoalloy shows significant advantages and broad application prospects in chemical catalysis, due to the possessed high specific surface energy and abundant active sites can greatly promote their catalytic performance. In this work, morphology-controlled Cu-Sn alloy nanosheet arrays supported on carbon fiber paper (CP) substrate (Cu-Sn/CP) have been developed by a facile one-step electrodeposition technique at room temperature for the first time. Benefiting from the large active surface area, considerable ion transport channels and strong synergistic catalytic effect between Cu and Sn, the as-prepared Cu-Sn/CP served as a self-supported electrode for efficient nonenzymatic glucose sensing. Under optimized conditions, Cu-Sn/CP electrode offers wide linear ranges of 0.0005–2.0 mM and 2.0–10.0 mM, respectively. The detection limit is as low as 0.061 μM (S/N = 3). Cu-Sn/CP electrode also exhibited excellent selectivity and stability. Additionally, the proposed sensor is proven to be suitable for the detection of glucose in human serum samples. [Display omitted] • Morphology-controlled Cu-Sn/CP was first synthesized by a cost-efficient one step electrodeposition strategy. • Non-precious Cu-Sn alloy nanosheets were used for the electrocatalytic oxidation of glucose for the first time. • Cu-Sn/CP showed high electrocatalytic activity for glucose oxidation with wide linear range and low detection limit. • The as-proposed biosensor exhibited excellent anti-interference ability and stability. [ABSTRACT FROM AUTHOR]

My comments concern the significant errors in the crystallographic part of the commented paper. [ABSTRACT FROM AUTHOR]

My comments concern the sever error in the crystallographic part of the commented paper. It was found that the studied crystal is of the sillenite type and the correct formula should be Bi 25 FeO 39 :Cd,Ti instead of some kind of solid solution based on BiFeO 3. Moreover, the type of unit cell is not correct. Due to the double doping the new type of unit cell, previously unknown, was proposed for such crystals. The actual chemical composition of the studied crystals is not known. [ABSTRACT FROM AUTHOR]

My comments concern the significant error in the crystallographic part of the commented paper. It was discovered that the studied crystals are of sillenite type and the correct formula should be Bi 25 FeO 39 :Ni,Ti instead of BiFeO 3. Moreover, the type of unit cell is not correct. Due to the doping the new type of unit cell, previously unknown, was proposed for such crystals. It was found that the studied sample contains two slightly different phases of the sillenite type. The actual chemical composition of the studied crystals is not known. [ABSTRACT FROM AUTHOR]

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]

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]

In alloy solidification, the transport processes of heat and solute result in morphological instability of the interface, forming different patterns of the solidification structure and determining the mechanical properties of components. As the first observable phenomenon of morphological instabilities, planar instability influences the subsequent stages significantly, deserving in-depth investigations. In this paper, the planar instability in alloy solidification under varying conditions is studied. First, the dynamical evolution of the planar instability is performed by the theoretical model and the phase-field model, respectively. Second, to represent the history-dependence of solidification, varying parameters are adopted in the simulations. Then, the criterion of planar instability under varying conditions is discussed. This paper considers that the critical parameters of planar instability are the excess free energy at the interface and the corresponding interfacial energy. Finally, to validate the criterion, comparisons between the phase-field and theoretical models are carried out, showing good consistency. Moreover, solidification processes with different preferred crystallographic orientations are performed, demonstrating the effect mechanism of the excess free energy and interfacial energy on planar instability. The idea of the interfacial energy influencing the planar instability could be applied to investigating other patterns induced by interfacial instability. [ABSTRACT FROM AUTHOR]

[Display omitted] Li-rich dual-phase Li-Cu alloy is a promising candidate toward practical application of Li metal anode due to its in situ formed unique three-dimensional (3D) skeleton of electrochemical inert LiCu x solid-solution phase. Since a thin layer of metallic Li phase appears on the surface of as-prepared Li-Cu alloy, the LiCu x framework cannot regulate Li deposition efficiently in the first Li plating process. Herein, a lithiophilic LiC 6 headspace is capped on the upper surface of the Li-Cu alloy, which can not only offer free space to accommodate Li deposition and maintain dimensional stability of the anode, but also provide abundant lithiophilic sites and guide Li deposition effectively. This unique bilayer architecture is fabricated via a facile thermal infiltration method, where the Li-Cu alloy layer with an ultrathin thickness around 40 μm occupies the bottom of a carbon paper (CP) sheet, and the upper part of this 3D porous framework is reserved as the headspace for Li storage. Notably, the molten Li can quickly convert these carbon fibers of the CP into lithiophilic LiC 6 fibers while the CP is touched with the liquid Li. The synergetic effect between the LiC 6 fibers framework and LiCu x nanowires scaffold can ensure a uniform local electric field and stable Li metal deposition during cycling. As a consequence, the CP capped ultrathin Li-Cu alloy anode demonstrates excellent cycling stability and rate capability. [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]

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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]

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]

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 this paper, a Zr–5W alloy was fabricated via casting. In order to obtain the mechanical properties of the material, quasi-static compression tests at room temperature and split Hopkinson pressure bar tests at various temperatures were carried out. The x-ray diffraction result showed that the main components of the alloy were αZr and W2Zr, where αZr is the matrix and W2Zr is the reinforcement. The metallographic characterization results showed that there were two main forms of W2Zr in the material, namely, large particle boundary and small diffuse submicrometer precipitates. The reinforcements of both distributions have the effect of increasing the strength of the material, but the small submicrometer W2Zr precipitates would cause microcrack nucleation during the late plastic deformation stage, resulting in damage softening. In order to make theoretical calculations of the mechanical properties of materials, the Johnson–Cook (JC) constitutive model and Zerilli–Armstrong (ZAM) constitutive model of the material were obtained. It was found that the JC constitutive model had poor consistency in describing material properties. Although the consistency of the ZAM constitutive model was higher than that of the JC constitutive model, it still had obvious shortcomings. Combined with the deformation mechanism of the alloy, a modified constitutive relation was established by adding damage softening terms based on the hexagonal close-packed metal constitutive model inferred by the kinetics of heat-activated dislocations. The relative error results of all working conditions show that the correlation consistency of the improved constitutive model in this paper is significantly better than that of JC constitutive and ZAM constitutive. [ABSTRACT FROM AUTHOR]

In this paper, by adding Cu alloy or Ni‐Au layer to Cu pad surface reduced the occurrence of pseudo welding and improve the rework strength and promoted the product stability and reliability. [ABSTRACT FROM AUTHOR]

As a destructive phenomenon with possible detrimental impact especially when it comes to human life, tribocorrosion has always been imperative to be researched. Hence, various investigations have outlined its influential role in the biomaterial apparatuses. Also, disparate routes have been introduced to address this problem. The use of several types of alloys, the application of various types of coatings, and the production of porous layers are some of these efforts made till now. Because of this issue's importance, and lack of a comprehensive review paper in this area of research, this paper shows an overview of existing publications in this area of research. This study presents the important ideas behind studies and provides a perspective of the research trend. In this exploration, the critical elements of the tribocorrosion-related studies were discussed thoroughly. The origin of the problem and the influential parameters in the process like loading, manufacturing, environment, and surface innate oxide film were scrutinized. Also, the efficacy of the use of different alloys, coatings, and the recommended modifications with respect to the tribocorrosion was discovered. We hope that this survey helps promote the emergence of new ideas for future research. [ABSTRACT FROM AUTHOR]

The paper presents analysis of influence of change of physical parameters such as: temperature, friction coefficient and load, during the process of die forging. Optimization of the process effects in achieving high quality products, decreasing shaping resistance, and what follows - lower energy consumption. Temperature is the basic factor affecting the process of plastic working. Analyzing that influence in individual die fragments, allows to engineer the flow of shaped material. The QForm3D commercial program for finite element method calculations was used for numerical simulations. The paper presents multi-variant analysis of forging process with the usage of numerical simulation, which provided many valuable information concerning changes of key parameters, such as: temperature, stress and strain distribution and variations of technological parameters, as well as their mutual influence, difficult to obtain in analysis of industrial process. [ABSTRACT FROM AUTHOR]

The CMT welding process has been widely used for aluminum alloy welding. The weld's penetration state is essential for evaluating the welding quality. Arc sound signals contain a wealth of information related to the penetration state of the weld. This paper studies the correlation between the frequency domain features of arc sound signals and the weld penetration state, as well as the correlation between Mel spectrograms, Gammatone spectrograms and Bark spectrograms and the weld penetration state. Arc sound features fused with multilingual spectrograms are constructed as inputs to a custom Inception CNN model that is optimized based on GoogleNet for CMT weld penetration state recognition. The experimental results show that the accuracy of the method proposed in this paper for identifying the fusion state of CMT welds in aluminum alloy plates is 97.7%, which is higher than the identification accuracy of a single spectrogram as the input. The recognition accuracy of the customized Inception CNN is improved by 0.93% over the recognition accuracy of GoogleNet. The customized Inception CNN also has high recognition results compared to AlexNet and ResNet. [ABSTRACT FROM AUTHOR]

This paper evaluates the effect of stress-relieving heat treatment on the AlSi10Mg alloy prepared by additive manufacturing using the Laser Powder Bed Fusion (L-PBF) with print parameters: 370 W, 1400 m/s, and 50 μm. The as-built state and four different annealing modes (240 °C/2 h, 240 °C/6 h, 300 °C/2 h, and 300 °C/2 h/water-quenched) are investigated. To determine the effect of the annealing mode on the mechanical properties of the L-PBF AlSi10Mg alloy, heat-treated samples were compared with the as-built state and with each other. The mechanical properties of the samples were determined by tensile and hardness tests. The strength in the as-built state is 488 MPa, depending on the method of heat treatment, the strength values range from 296 MPa to 417 MPa, and the HV10 hardness values are in accordance with the measured strength values. Furthermore, the microstructure of the samples was investigated by scanning electron microscopy (SEM) analysis, which was then linked to the measured mechanical properties. The composition of the microstructure of the alloy and its influence on the mechanical properties were determined by energy dispersive spectroscopy (EDS) analysis. Furthermore, the differences between the individual heat treatments in comparison with the as-built state were analyzed and the phenomenon of decomposition of the silicon network after reaching specific temperatures was discussed and confirmed. The paper evaluates the effect of dwelling time on stress relief annealing. It was found that if annealing at intermediate temperatures of 240 and 300 °C is applied, changes in structure and mechanical properties are more temperature- than dwell-time-dependent. [ABSTRACT FROM AUTHOR]

The development of effective and selective catalysts is the key to improving the multi-electron transfer nitrate reduction reaction (NO3−RR) to ammonia (NH3). Herein, we prepared a copper–tin bimetallic alloy using the dynamic hydrogen bubble template electrodeposition technique for electrocatalytic NO3− reduction to NH3. The NH3 yield rate and the faraday efficiency were up to 293.12 μmol h−1 cm−2 and 78.57% at −1.2 V versus reversible hydrogen electrode in 0.1 M Na2SO4 (containing 0.01 M NaNO3) electrolyte. This paper will provide new suggestions for the use of bimetallic alloys for electrochemical removal of nitrate and ammonia synthesis from water. [ABSTRACT FROM AUTHOR]

In this paper, compositions within the TiZrAlCrMn, TiZrAlCrFe, and TiZrAlMnFe alloy systems that form the C14 Laves phase are investigated. The design, synthesis, structural, and hydrogen storage characterizations for an equiatomic and a non‐equiatomic composition for each alloy system are presented. Additionally, the further development of a thermodynamic method for the calculation of pressure‐composition‐isotherms (PCIs) is presented of C14 Laves phase alloys that absorb hydrogen by solid solution. Overall, the results shown in this paper indicate that Al‐containing multicomponent alloys can present promising hydrogen storage performance under high pressures. Nonetheless, high concentrations of aluminum in highly concentrated (equiatomic) alloys can have a negative impact on the hydrogenation properties. The Ti0.29Zr0.05Al0.05Cr0.26Mn0.35 composition showed promising hydrogenation/dehydrogenation properties. The gravimetric capacity of this alloy is ≈1.76 wt.% H2 and the PCIs measured indicate that this material has potential for high‐pressure hydrogen storage and compression applications. The use of the presented thermodynamic model for the design of multicomponent alloys is suggested. [ABSTRACT FROM AUTHOR]

The present review paper addresses the increasing interest in the application of machine learning (ML) algorithms in the assessment of the fatigue response of additively manufactured (AM) metal alloys. This review aims to systematically collect, categorize, and analyze relevant research papers in this domain. The most commonly used ML algorithms are presented, discussing their specific relevance to the fatigue modeling of AM metal alloys. A detailed analysis of the most relevant input features used in the literature to predict the main parameters related to the fatigue response is provided. Each work has been analyzed to highlight its strengths and peculiarities, thereby offering insights into novel methodologies and approaches for addressing critical challenges within this field. Particular attention is dedicated to the role of defects and the related size‐effect, as they strongly influence the fatigue response. In conclusion, this review not only synthesizes existing knowledge but also offers forward‐looking recommendations for future research directions, providing a valuable resource for researchers in the domain of ML‐assisted fatigue assessment for AM metal alloys. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) is a technology that builds parts layer by layer. Over the past decade, metal additive manufacturing (AM) technology has developed rapidly to form a complete industry chain. AM metal parts are employed in a multitude of industries, including biomedical, aerospace, automotive, marine, and offshore. The design of components can be improved to a greater extent than is possible with existing manufacturing processes, which can result in a significant enhancement of performance. Studies on the anisotropy of additively manufactured metallic materials have been reported, and they describe the advantages and disadvantages of preparing different metallic materials using additive manufacturing processes; however, there are few in-depth and comprehensive studies that summarize the microstructural and mechanical properties of different types of additively manufactured metallic materials in the same article. This paper begins by outlining the intricate relationship between the additive manufacturing process, microstructure, and metal properties. It then explains the fundamental principles of powder bed fusion (PBF) and directed energy deposition (DED). It goes on to describe the molten pool and heat-affected zone in the additive manufacturing process and analyzes their effects on the microstructure of the formed parts. Subsequently, the mechanical properties and typical microstructures of additively manufactured titanium alloys, stainless steel, magnesium–aluminum alloys, and high-temperature alloys, along with their anisotropy, are summarized and presented. The summary indicates that the factors leading to the anisotropy of the mechanical properties of metallic AM parts are either their unique microstructural features or manufacturing defects. This anisotropy can be improved by post-heat treatment. Finally, the most recent research on the subject of metal AM anisotropy is presented. [ABSTRACT FROM AUTHOR]

The microstructure of three rolling surfaces of TC4 sheet is different, and their resistance ability to hydrogen damage lacks systematic research. Thus, the hydrogen damage behavior of TC4 rolling sheet was investigated in this paper. The hydrogen diffusion law along different rolling directions and the precipitation of hydrides on different rolling surfaces were compared. It is found that the shape and distribution of α and β phases are changed under the action of extrusion force during the rolling process, and they are arranged in striped shape on the R-N surface along the R direction, and the diffusion of hydrogen along the R direction is faster due to the existence of continuous β phases as hydrogen diffusion channels, resulting in the more serious hydrogen damage. Besides the hydrides mainly deposited at the α and β phase boundaries, the hydrides precipitated in the interior of α phases on the R-N surface are more than that on the R-T surface due to the different distribution state of β phases. [ABSTRACT FROM AUTHOR]

Software reliability modeling, as a non-functional characteristic of software quality to achieve high reliability, is of particular importance. To obtain software systems with high reliability, it is important to select the best scenario, from the various scenarios produced, in a short time during the software design stage. Since the scenario includes interactions between the user and use case, producing various scenarios and selecting the best among them in terms of reliability is a difficult and time-consuming task for software designers. Therefore, it is of great importance to use a modeling language that has a tool-based evaluation modeling approach and does the analysis automatically. In this paper, Alloy modeling language has been used to model and analyze software reliability. Compared to other lightweight modeling languages, Alloy has such advantages as being more concise, accurate and abstract. The primary objective of this paper aims to present a modeling framework based on the Alloy modeling language with which reliability of target systems can be efficiently examined. The results indicate that the use of Alloy analyzer facilitates the immediate production of various scenarios and allows for the selection of the best one in terms of reliability. [ABSTRACT FROM AUTHOR]

This paper presents corrosion resistance results of a 12Cr ferritic ODS steel (Fe-12Cr-2W-0.5Zr-0.3Y2O3) fabricated via a powder metallurgy route as a prospective applicant for fuel cladding materials. In a spent nuclear fuel reprocessing facility, nitric acid serves as the primary solvent in the PUREX method. Therefore, fundamental immersion and electrochemical tests were conducted in various nitric acid solutions to evaluate corrosion degradation behavior. Additionally, polarization tests were also performed in 0.61 M of sodium chloride solutions (seawater-like atmosphere) as a more general, all-purpose procedure that produces valid comparisons for most metal alloys. For comparison, martensitic X46Cr13 steel was also examined under the same conditions. In general, the corrosion resistance of the 12Cr ODS steel was better than its martensitic counterpart despite a lower nominal chromium content. Potentiodynamic polarization plots exhibited a lower corrosion current and higher breakdown potentials in chloride solution in the case of the ODS steel. It was found that the corrosion rate during immersion tests was exceptionally high in diluted (0.1–3 M) boiling nitric acid media, followed by its sharp decrease in more concentrated solutions (>4 M). The results of the polarization plots also exhibited a shift toward more noble corrosion potential as the concentrations increased from 1 M to 4 M of HNO3. The results on corrosion resistance were supported by LSCM and SEM observations of surface topology and corrosion products. [ABSTRACT FROM AUTHOR]

Titanium-based alloys are a widely applicable engineering material with high strength, low weight, non-magnetic, and corrosion resistance. At the same time, resistance to low temperatures is declared, which offers the material's applicability for, e.g., aircraft or ship technology. Additive technologies are part of the industrial spectrum of material processing, especially the Laser Powder Bed Fusion of Metals method for metal alloys, which creates a layered structure of the resulting body. The topology of the internal structure, in relation to the temperature history of the functional environment, influences thermal expansion and the associated functional characteristics. Knowledge of the thermal expansion of printed strength and non-strength functional components and accessories is essential for future applications, especially in environments with high repeatable temperature changes, such as the aerospace industry. This paper presents the results of testing the expansion, mechanical, microstructural, and mineralogical characteristics of Ti6Al4V over the temperature range of −70 to 60 °C using a combination of instrumental techniques such as X-ray diffraction and nanoindentation. It was found that the topological orientations of the printed samples directly influenced the tested properties, e.g., the coefficient of thermal expansion in the direction perpendicular to the printed layers showed approximately 12% lower value compared to the other directions. Due to the progression of the application of the manufacturing method and its applicability within selected industries, the research provides results in a new area, which is supported by the relevant research. [ABSTRACT FROM AUTHOR]

The non-equilibrium solidification process in the additive manufacturing of titanium alloy leads to special microstructures, and the resulting changes in corrosion behavior are worthy of attention. In this paper, the microstructure and electrochemical corrosion behavior of Ti6Al4V alloys prepared using laser powder bed melting (LPBF) and casting are systematically compared. The results show that the LPBF-processed Ti6Al4V alloy is composed of dominant acicular α′ martensite within columnar prior β phase, and less β disperses have also been discovered, which is significantly different from the α + β dual-phase structure of cast Ti6Al4V alloy. Compared to the as-cast Ti6Al4V alloy, LPBF-processed Ti6Al4V alloy has a thinner and unstable passive film, and exhibits slightly poorer corrosion resistance, which is mainly related to its higher porosity, a large amount of acicular α′ martensite and less β phase compared to as-cast Ti6Al4V alloy. This result proves that suitable methods should be taken to control the relative density and phase composition of LPBF-processed Ti6Al4V alloys before application. [ABSTRACT FROM AUTHOR]

Phase contrast is widely used in all fields for visualization of the internal structure of objects using Xray radiation. The paper proposes a new approach to modeling a phase-contrast X-ray image by the method of free propagation using the Fresnel-Kirchhoff diffraction theory. A simple calculation model was developed, which makes it possible to determine the value of the change in the intensity of X-rays on three-dimensional models of objects of arbitrary shape with macroscopic dimensions. It also allows you to establish the conditions for observing a contrast image with known characteristics of the detector system and the intensity of the radiation source. The possibility of obtaining clear images of objects with small decrements of refraction of matter, determining their geometric dimensions and thickness was shown. A method of calculating the optical properties of metal alloys in the X-ray range has been developed. The approaches presented in the paper can be useful to developers of compact devices for detecting structural inhomogeneities inside the studied objects by a non-destructive method. [ABSTRACT FROM AUTHOR]

Hydrogen embrittlement (HE) remains a pressing issue in materials science and engineering, given its significant impact on the structural integrity of metals and alloys. This exhaustive review aims to thoroughly examine HE, covering a range of aspects that collectively enhance our understanding of this intricate phenomenon. It proceeds to investigate the varied effects of hydrogen on metals, illustrating its ability to profoundly alter mechanical properties, thereby increasing vulnerability to fractures and failures. A crucial section of the review delves into how different metals and their alloys exhibit unique responses to hydrogen exposure, shedding light on their distinct behaviors. This knowledge is essential for customizing materials to specific applications and ensuring structural dependability. Additionally, the paper explores a diverse array of models and classifications of HE, offering a structured framework for comprehending its complexities. These models play a crucial role in forecasting, preventing, and mitigating HE across various domains, ranging from industrial settings to critical infrastructure. [ABSTRACT FROM AUTHOR]

MCrAlY (M = Ni and/or Co) metallic coatings are essential for the protection of hot-end components against thermal and corrosion damage. Increasing the Al content is considered a feasible solution to improve the high-temperature performance of MCrAlY coatings. In this paper, the effects of high Al contents (12–20 wt.%) on the phase constituents and cast microstructures in MCrAlY alloys were studied by high-energy X-ray diffraction and electron microscopy techniques combined with phase equilibria calculations. High Al content improved the stability of β, σ, and α phases. Meanwhile, an evolution of the cast microstructure morphology from a dendrite structure to an equiaxed grain structure was observed. The thermal properties were analyzed, which were closely related to the phase constituents and solid-to-solid phase transitions at evaluated temperatures. This work is instructive for developing high-Al-content MCrAlY coatings for next-generation thermal barrier applications. [ABSTRACT FROM AUTHOR]

This paper reports the results of our study on electrochemical polishing of titanium and a Ti-based alloy using non-aqueous electrolyte. It was shown that electropolishing ensured the removal of surface defects, thereby providing surface smoothing and decreasing surface roughness. The research was conducted using samples made of titanium and Ti6Al4V alloy, as well as implant system elements: implant analog, multiunit, and healing screw. Electropolishing was carried out under a constant voltage (10–15 V) with a specified current density. The electrolyte used contained methanol and sulfuric acid. The modified surface was subjected to a thorough analysis regarding its surface morphology, chemical composition, and physicochemical properties. Scanning electron microscope images and profilometer tests of roughness confirmed significantly smoother surfaces after electropolishing. The surface profile analysis of processed samples also yielded satisfactory results, showing less imperfections than before modification. The EDX spectra showed that electropolishing does not have significant influence on the chemical composition of the samples. [ABSTRACT FROM AUTHOR]

In industrial production, the deformation inhomogeneity after metal forging affects the mechanical properties of various parts of the forgings. The question of whether the organization and mechanical properties of β-titanium alloy can be improved by controlling the amount of forging deformation needs to be answered. Therefore, in this paper, a new sub-stable β-Ti alloy TB 18 (Ti-5.3Cr-4.9Mo4.9V-4.3Al-0.9Nb-0.3Fe) was subjected to three different levels of deformation, as well as solid solution-aging treatments, and the variation rules of microstructure and mechanical properties were investigated. During the solid solution process, the texture evolution pattern of the TB18 alloy at low deformation (20–40%) is mainly rotational cubic texture deviated into α-fiber texture; at high deformation (60%), the main components of the deformed texture are α-fiber texture with a specific orientation of (114)<1 13 - 3>. After subsequent static recrystallization, the α-fiber texture is deviated to an α*-fiber texture, while the specific orientation (114)<1 13 - 3> can still be inherited as a major component of the recrystallized texture. The plasticity of the alloy in the normal direction (ND) after the solid solution is influenced by the existence of the <110>//ND texture, and the plasticity of the alloy in the ND direction after aging is determined by a combination of the volume fraction of the <110>//ND texture in the matrix phase and the volume fraction of [11 2 - 0]α//ND in the α phase. The results show that it is feasible to change the characteristics of the recrystallization texture of TB18 by controlling the deformation level of hot forging, thus realizing the modulation of the mechanical properties. [ABSTRACT FROM AUTHOR]

Based on the first principle, this paper uses the generalised gradient approximation density functional theory and slab model to investigate the dissociation of methane (CH4→CH3 + H) on the surfaces of Co group (Co, Rh, Ir) and Ni group (Ni, Pd, Pt), and investigate the influence of PtIr(100), PdRh(100) and PtPd(100) on methane decomposition. From the calculated activation energies of methane dissociation on single metal surfaces and alloy surfaces,we find that Pt and Ir are better catalysts for methane dissociation in the single metals studied. In addition, methane dissociation (CH4→CH3 + H) on PtIr(100) and PdRh(100) surfaces are easier than that on single metal surfaces(Co, Rh, Ir, Ni, Pd, Pt). [ABSTRACT FROM AUTHOR]

This paper reports on the development and validation of a formal model for an automotive adaptive exterior lights system (ELS) with multiple variants in Alloy 6, which is the most recent version of the Alloy lightweight formal specification language that supports mutable relations and temporal logic. We explore different strategies to address variability, one in pure Alloy and another through an annotative language extension. We then show how Alloy and its Analyzer can be used to validate systems of this nature, namely by checking that the reference scenarios are admissible, and to automatically verify whether the established requirements hold. A prototype was developed to translate the provided validation sequences into Alloy and back to further automate the validation process. The resulting ELS model was validated against the provided validation sequences and verified for most of requirements for all variants. [ABSTRACT FROM AUTHOR]

Aluminium-Silicon (Al-Si) based alloys are gaining more prominence among researchers for automotive applications. In this paper, the impact of copper alloying element and artificial ageing treatment on the mechanical response and microstructural evolution of Al-Si based alloys synthesised from aluminium scrap are examined, as there is need to gear up the urge for the usage of metallic scraps for production of alloys for automotive applications. The as-cast Al-Si alloy and its form with copper as alloying element (1.5% and 3% Cu) were produced using liquid metallurgy route. Solution heat treatment was carried out at 500℃ and artificial ageing was carried out at 190℃ for 0.5, 1, 1.5, 2 and 2.5 h. Mechanical properties and microstructural characterisations of the as-cast and artificially aged forms of Al-Si based alloys were performed. The hardness tests were performed according to ASTM A29/A29M–15. Impact strength was determined according to ASTM D256. Tensile tests were performed based on ASTM E8. Microstructures of the synthesised Al-Si alloys were examined using optical microscopy and scanning electron microscopy techniques. In as-cast condition of the Al-5Si-Cu alloy, impact strength increases with increase in copper content. Al5Si-Cu alloy with 3% copper content and artificially aged at 190°C for 2.5 h exhibited the highest impact strength. Hardness number increases with the increase in copper content up to 1.5% and the ageing time. Additional increase in the ageing time yielded decrease in the hardness number. Results revealed that artificial ageing enhances mechanical and microstructural characteristics of the Al-Si alloys. Ageing treated Al-Si alloys exhibited peak hardness, impact strength and ultimate tensile strength (UTS) values of 77.47 kgf/mm2, 17 J/mm2 and 137.80 MPa, respectively. The obtained results are indicative of mechanical properties enhancement when compared with as-cast Al-Si alloys with maximum hardness, impact strength and UTS of 43.71 kgf/mm2, 12.92 J/mm2 and 123.18 MPa, respectively. Significant improvement in mechanical properties was achieved in Al-Si-Cu alloy with copper content and artificial ageing when compared to that without copper inclusion. This may be attributed to the evolution of equiaxed precipitates and the fact that copper-rich Al-Si-Cu alloys promotes formation of precipitation strengthening phases of α-AlFeMnSi. This study shows that the mechanical properties of Al-5Si-Cu alloys produced using aluminium scrap-based materials were enhanced using artificial ageing treatment and the benefit can be utilised for automotive applications. [ABSTRACT FROM AUTHOR]