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The effect of hydrogen diffusion and trapping was studied in a high-Cr ferrous alloy using an inverted scanning Kelvin probe and thermal desorption spectroscopy in correlation with microstructure and residual stress study. In addition, different processing of ferritic/martensitic 9Cr1WTaV alloy (EUROFER97) was tested in correlation with observed selected properties to observe induced changes in material degradation and surface. The activation energies for hydrogen traps were shown to have distinct peaks corresponding to different trapping mechanisms, including matrix dislocations and grain boundaries. For the cryogenically treated sample, an additional peak was also identified and correlated with increased carbide precipitation. [ABSTRACT FROM AUTHOR]

Depending on the specific alloy composition and iron content, iron can have various effects on aluminum alloys. This work examines the influence of varying Fe content on the Charpy impact, tensile, and hardness properties of cast AlSi7Mg0.3 alloy (356). The samples contained 0.11, 0.25, 0.42, and 0.65 wt% Fe levels. The instrumented Charpy V-notch impact tests, conducted according to the ISO EN 148-3 standard, provided data on maximum impact force, crack initiation, crack propagation, and total Charpy impact resistances. Tensile tests, performed according to EN ISO 6892-1 standard, evaluated the yield strength (YS), ultimate tensile strength (UTS), and elongation (%ε) values. Hardness and density measurements were also taken. Additionally, the fracture surfaces of Charpy V-notch and tensile test samples underwent optical macroscopic and scanning electron microscopic analysis to understand the effects of Fe content. The study revealed that as the Fe content in AlSi7Mg0.3 alloy increases, the tensile properties and Charpy impact resistances decrease. [ABSTRACT FROM AUTHOR]

Materials like metallic iron and its alloys are essential to daily living and industrial production. The benefits of using electrolysis technology to prepare iron and its alloys are great efficiency, controllability, and environmental protection. This study focuses on the feasibility of the electrochemical method for the direct preparation of metallic iron and Si–Fe alloys in iron ores with high fluoride content. The electrochemical behavior of Fe(II) and Fe(III) in molten SiO2–CaO–CaF2 slag on tungsten electrodes was investigated by using cyclic voltammetry and square wave voltammetry methods. It was determined that the reduction of Fe(II) ions follows a one-step two-electron transfer process: Fe(II) + 2e− → Fe(0). The reduction of Fe(III) involves a two-step electron transfer process: Fe(III) + e− → Fe(II) and Fe(II) + 2e− → Fe(0), respectively. The Fe(II)/Fe(0) process is an irreversible reaction controlled by diffusion. The diffusion coefficient of Fe(II) is DFe(II) = 1.5 × 10−6 cm2 s−1. The cathodic deposits of iron were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) combined with energy dispersive X-ray spectroscopy (EDS). The findings indicate that the production of Fe2Si alloy through electrolysis is more favorable when Fe(II) is present in the slag, while the production of metallic iron is more favorable when Fe(III) is present in the slag. This work provides a basis for the electrochemical direct preparation of Fe–Si alloy and metallic iron in high fluorine iron ore. [ABSTRACT FROM AUTHOR]

The influence of dopant molecules on the structure and functionality of spin-crossover (SCO) materials is surveyed. Two aspects of the topic are well established. Firstly, isomorphous inert metal ion dopants in SCO lattices are a useful probe of the energetics of SCO processes. Secondly, molecular alloys of iron(II)/triazole coordination polymers containing mixtures of ligands were used to tune their spin-transitions towards room temperature. More recent examples of these and related materials are discussed that reveal new insights into these questions. Complexes which are not isomorphous can also be co-crystallised, either as solid solutions of the precursor molecules or as a random distribution of homo- and hetero-leptic centres in a molecular alloy. This could be a powerful method to manipulate SCO functionality. Published molecular alloys show different SCO behaviours, which may or may not include allosteric switching of their chemically distinct metal sites. [ABSTRACT FROM AUTHOR]

An Fe-based amorphous coating, with the composition Fe48Cr15Mo14C15B6Y2, was synthesized by the high-velocity oxygen fuel spray (HVOF) process on a substrate of AISI 1035. The effect of crystallization on the electrochemical and tribological properties of the HVOF-sprayed Fe-based coating was systematically studied. The XRD results validated the fully amorphous nature of the as-sprayed coating by showing a broad peak at 43.44° and crystallization of this coating after heat-treatment at 700 °C by demonstrating sharp peaks of Fe-, Mo-, and Cr-based carbides. After crystallization, an increase in the corrosion current density from 4.95 μAcm−2 to 11.57 μAcm−2 and in the corrosion rate from 4.28 mpy to 9.99 mpy, as well as a decrease in the polarization resistance from 120 Ωcm2 to 65.12 Ωcm2, were observed, indicating the deterioration of the corrosion resistance of the as-sprayed Fe-based coating. This can be attributed to the formation of porous ferrous oxide, providing an easy channel for charge transfer and promoting pit formation. However, a decrease in the coefficient of friction from 0.1 to 0.05 was observed, highlighting the significant improvement in the wear resistance of the Fe-based coating after crystallization. This can be associated with the precipitation of hard carbides (MxCy) at the boundaries of the crystallized regions. [ABSTRACT FROM AUTHOR]

The paper presents the results of testing the wear resistance and coefficient of friction (COF) tools made of SikaBeresin® F50 polyurethane resin intended for dies and punches for the cold sheet metal forming process. Seven sets of composite tools (rotating rings) additionally reinforced with waste metallic powders from Al and Cu alloys (5-20% by volume) from the dry cutting process of pipes and rods were tested. Wear resistance tests and determination coefficient of friction were carried out using the T-05 block-on-ring tribotester. The tests were performed for heat and corrosion resistant sheets made of nickel alloy AMS5599 (Inconel 625), iron alloy AMS5510 (321) and aluminum alloy sheets AMS4026 (6061-T4). Composite tools with the addition of 20% aluminum powder (A+B+C+20%Al) tested with a specimen of steel alloy AMS5510 and nickel alloy AMS5599 were characterized by the lowest wear resistance. In each case, the composite rotating ring without reinforcements was characterized by the lowest coefficient of friction. The use of Cu powder reinforcements in each case had a positive effect on increasing wear resistance. The best wear resistance of 0.011% was obtained for composite rotating ring with the addition of 10% copper powder paired with specimen of nickel alloy AMS5599 sheet. [ABSTRACT FROM AUTHOR]

Nowadays, the use of metal processing additive technologies is a rapidly growing field in the manufacturing industry. These technologies, such as metal 3D printing (also known as additive manufacturing) and laser cladding, allow for the production of complex geometries and intricate designs that would be impossible with traditional manufacturing methods. They also offer the ability to create parts with customized properties, such as improved strength, wear resistance, and corrosion resistance. In other words, these technologies have the potential to revolutionize the way we design and produce products, reducing costs and increasing efficiency to improve product quality and functionality. One of the significant advantages of these metal processing additive technologies is a reduction in waste and environmental impact. However, there are also some challenges associated with these technologies. One of the main challenges is the cost of equipment and materials, which can be prohibitively expensive for small businesses and individuals. Additionally, the quality of parts produced with these technologies can be affected by factors such as printing speed, temperature, and post-processing methods. This review article aims to contribute to a deep understanding of the processing, properties, and applications of ferrous and non-ferrous alloys in the context of SLM to assist readers in obtaining high-quality AM components. Simultaneously, it emphasizes the importance of further research, optimization, and cost-effective approaches to promote the broader adoption of SLM technology in the industry. [ABSTRACT FROM AUTHOR]

In order to improve the mechanical properties of the wear-resistant layer of the hob cutter ring in shield construction, the influence of different composite matrix powders on the comprehensive performance of the cladding layer was investigated. In this study, TiC-reinforced Fe-Ni-based cladding layers with different matrix compositions were prepared on a modified H13 steel base material using plasma cladding (PC) technology. The matrix powders included Ni-based alloy powder, iron powder Y, and iron powder R. The two iron powders were mixed in different proportions, and then an equal amount of Ni-based alloy powder and TiC ceramic particles were added to form five kinds of composite cladding layer alloy powders. The cladding layers of five different matrices were obtained by cladding. The microstructure and mechanical properties of the composite cladding layer were studied using a metallographic microscope (OM), an X-ray diffractometer (XRD), a scanning electron microscope (SEM), an energy dispersive spectrometer (EDS), an electronic universal testing machine, an image processing microhardness tester, and an abrasive belt friction and wear testing machine. The results showed that the cladding layers of different samples had good metallurgical bonding with the base material. And the microstructure gradually refined from the bottom of the cladding layer to the top of the cladding layer. The cladding layer phases were mainly composed of Fe, FeO, TiC, FeNi, and CrNi. With the increase in the iron powder R ratio, the aggregation of alloy elements gradually alleviated. The ratio of iron powder R was increased from 1/10 to 2/5, the longitudinal shear strength between the cladding layer and the matrix was increased from 318 Mpa to 333 Mpa, and the transverse shear strength was increased from 303 Mpa to 342 Mpa. The hardness of the modified wear-resistant layer was better than that of the cladding layer without iron powder R, but the hardness of the cladding layer gradually decreased. After the modification of iron powder R, the wear resistance of the cladding layer was improved to varying degrees. When Y:R was 9:1, its wear resistance was the best, and the change trend of the wear resistance was consistent with that of hardness. The wear forms of different samples were adhesive wear and abrasive wear. And the height difference of the wear surface gradually increased with the improvement in wear resistance. [ABSTRACT FROM AUTHOR]

Classification of cast iron alloys based on graphite morphology plays a crucial role in materials science and engineering. Traditionally, this classification has relied on visual analysis, a method that is not only time‐consuming but also suffers from subjectivity, leading to inconsistencies. This study introduces a novel approach utilizing convolutional neural networks—MobileNet for image classification and U‐Net for semantic segmentation—to automate the classification process of cast iron alloys. A significant challenge in this domain is the limited availability of diverse and comprehensive datasets necessary for training effective machine learning models. This is addressed by generating a synthetic dataset, creating a rich collection of 2400 pure and 1500 mixed images based on the ISO 945‐1:2019 standard. This ensures a robust training process, enhancing the model's ability to generalize across various morphologies of graphite particles. The findings showcase a remarkable accuracy in classifying cast iron alloys (achieving an overall accuracy of 98.9 ± 0.4%—and exceeding 97% for all six classes—for classification of pure images and ranging between 84% and 93% for semantic segmentation of mixed images) and also demonstrate the model's ability to consistently identify and graphite morphology with a level of precision and speed unattainable through manual methods. [ABSTRACT FROM AUTHOR]

The strategic regulation of the electronic properties and coordination environment of single‐atom sites through the integration of metal nanoclusters emerges as a promising route to enhance the oxygen reduction reaction (ORR) performance of Fe–N–C materials. Here, a catalyst (FeIn–NC) is successfully developed in which Fe–N–C materials encapsulate Fe–In alloy nanoclusters, and it shows excellent ORR activity and durability under alkaline conditions, with a high half‐wave potential of 0.924 V (vs RHE) and a zinc–air battery power density of 202.1 mW cm−2, superior to commercial Pt/C catalysts. Theoretical calculations unravel that the synergistic interaction between the Fe–In alloy and the FeN4 single‐atom site modifies the electronic structure and charge distribution at the FeN4 site, thereby enhancing the electrocatalytic activity and durability of the ORR. Potential‐dependent microkinetic modeling (MKM) further discloses the ORR mechanisms on the identified FeN4 sites. This work provides a viable strategy for the ORR improvement of Fe–N–C materials via p‐block metal‐based alloy nanoclusters. [ABSTRACT FROM AUTHOR]

In this study, pure iron, S45C carbon steel (Fe–0.45mass%C), carburized iron, and nitrided iron are bonded with two types of stainless steels, i.e., SUS304 austenitic stainless steel (Fe–18mass%Cr–8mass%Ni) with face center cubic structure or SUS430 ferritic stainless steel (Fe–18mass%Cr) with body center cubic structure by a spark plasma sintering (SPS) machine. Bonding experiments are carried out by SPS bonding. It is found that the bonding temperature of the S45C/SUS samples is lower than that of Fe/SUS samples, and carbon atoms in the S45C play important role on the bonding performance. The bonding temperature for SUS304/SUS430 sample is more than 30 °C higher than those for the Fe/SUS and S45C/SUS samples. The presence of thin chromium oxides on both stainless steels reduces the bonding performance of SUS304/SUS430 sample. Better bonding performance is found for the carburized and nitrided iron for bonding with stainless steels. However, continuous single‐phase layer on the surface leads to reduce the bonding performance. It is concluded that not only the concentration of carbon and nitrogen but also the phase configuration in the iron at interface strongly influences the bonding performance between iron alloys and stainless steels by SPS bonding. [ABSTRACT FROM AUTHOR]

This experimental investigation is the first to generate a surface iron-tantalum (Fe/Ta) alloy as a sublayer-layer using a plasma focus device. Examining how ion beams from a plasma focus device alloy iron and tantalum with varying melting points is one of the key objectives of this study. Fe/Ta thin film nanostructure and surface morphology were also examined. The distance from the tip anode and the varied number of shots are the experimental variables. Although tantalum's melting point (3020 ∘ C ) is generally known to be near to that of iron (2862 ∘ C ), it is possible that iron vaporizes and partial alloying of iron with tantalum occurs before tantalum reaches its melting point. Fe/Ta thin film identification techniques include scanning electron microscopy, mapping of cross-section, energy dispersive X-ray spectroscopy, and X-ray diffraction pattern. Additionally, the composition of multilayer structures is examined using EDS. In conclusion, the results of the X-ray diffraction pattern showed that the number of shots had a significant impact on the residual strain degree of the thin films that were deposited. Furthermore, structures made of FeTa and Fe2Ta were produced. Additionally, photos from scanning electron microscopy and cross-section mapping verify that the sample with five shots at an 8 cm distance from the tip anode formed a uniform Fe/Ta alloy structure. The sample with five shots at a distance of 4 cm from the tip anode formed micro-island structures, as seen by scanning electron microscopy, with decreasing distance. Furthermore, depth elemental distribution revealed that the optimal depth of penetration in a homogenous material to develop alloying is best determined by number of PF shots. Highlights: Selected parameters of experiment impact on the lattice parameters, as well as the fabricating Fe2Tahexagonal and FeTarhombohedral structures. The degree of residual strain in the crystal lattice of the thin films, remarkably dependent on the number of shots. Homogenous alloy only observed in one sample. The creation of black-lines and micro-structures is attributed to enhance of O2 ratio. [ABSTRACT FROM AUTHOR]

Three titanium alloys with 0.5, 6, and 9 wt.% iron were investigated, and the samples were pre-annealed in three different regions of the Ti–Fe phase diagram, namely β, α+β, and α+FeTi. After annealing, five samples of different phases and structural compositions were studied. They were then subjected to the high-pressure torsion (HPT). The microstructure of the samples before and after HPT treatment was studied using transmission and scanning electron microscopy. The microstructure of the samples obtained during heat treatment before HPT treatment had a fundamental effect on the microstructure after HPT. Grain boundary layers and chains of particles formed during the annealing process made it difficult to mix the material during HPT, which led to the formation of areas with non-uniform mixing of components. Thus, the grain boundary layers of the α-phase formed in the Ti–6wt % Fe alloy after annealing at 670 °C significantly decreased the mixing of the components during HPT. Despite the fact that the microstructure and phase composition of Ti–6wt % Fe alloys pre-annealed in three different regions of the Ti–Fe phase diagram had significant differences, after HPT treatment, the phase compositions of the studied samples were quite similar. Moreover, the measured micro- and nanohardness as well as the Young's modulus of Ti–6wt % Fe alloy had similar values. It was shown that the microhardness of the studied samples increased with the iron content. The values of nanohardness and Young's modulus correlated well with the fractions of β- and ω-phases in the studied alloys. [ABSTRACT FROM AUTHOR]

Recent seismological studies of the Martian core revealed its relatively low density, suggesting the presence of large amounts of light elements including oxygen and carbon in addition to sulfur. In order to reveal crystallizing solids in the light-element-rich core of Mars, we performed high-pressure melting experiments on Fe-S-O-C alloys at 26–49 GPa using a laser-heated diamond-anvil cell. The liquidus phase relations in the Fe-S-O-C system were determined based on textural and chemical characterizations of recovered samples. The results show that Fe-S-O-C liquids crystallize FeO or Fe 3 C in the presence of small amounts of O or C in liquids. Accordingly the liquidus fields of Fe 3 S and Fe 2 S are small, and the quaternary eutectic point is found to be close to the Fe-Fe 3 S binary eutectic point. Under Martian core conditions, S-rich liquids have low liquidus temperatures to crystallize FeO or Fe 3 C compared to S-poor liquids. The pressure dependence of liquidus temperatures suggests that crystallization of Mars' core starts at the center upon cooling. According to the FeO-Fe 3 C cotectic surfaces and their liquidus temperatures, an FeO and/or Fe 3 C inner core is predicted unless the Martian core remains entirely liquid. [ABSTRACT FROM AUTHOR]

In this work, wire arc additive manufactured (WAAM-ed) Inconel 617- and 625-wmo grade alloys are characterized in detail for the type and distribution of precipitates in as-built and heat-treated conditions. The analyses are carried out near (~1 mm) and away (~10 mm) from the substrate along the build direction to investigate the effect of the substrate on the nature of precipitate formation. For each analysis location, morphological and chemical information of at least 400 precipitate features was identified and classified using stoichiometric analysis of SEM-EDS data combined with feature analytics. Carbides and carbonitrides are present in both Inconel 600 series alloys but Laves phase precipitates are identified only in the case of Inconel 625 wmo alloy. It is observed that the nature of precipitates size distribution is not altered significantly when compared between the two analysed locations for a particular grade. Furthermore, Laves phase precipitates closer to the substrate (1 mm) are richer in iron because of the effect of mild steel substrate on precipitation characteristics in Inconel 625 alloy. Our novel characterization approach will pave the way for comparing the microstructures of additively manufactured samples printed using different process parameters and variations. [ABSTRACT FROM AUTHOR]

Worldwide, light water reactors (LWRs) have been using zirconium (Zr)-based alloys for the cladding of the uranium dioxide fuel for more than 6 decades. Zr alloys oxidize rapidly in the presence of water and steam at temperatures > 450°C; therefore, they do not respond well to scenarios of loss of coolant accidents. There is a global effort by nuclear materials technologists to find more robust or stronger cladding materials for LWRs. One option is to use an iron-chromium-aluminum (FeCrAl) alloy since they have excellent resistance to high temperature oxidation and superior mechanical properties at LWR operation temperatures. Results show that (1) FeCrAl alloys have better mechanical properties than Zr alloy and are orders of magnitude more resistant to creep at temperatures higher than LWR normal operation conditions. (2) FeCrAl alloys have better resistance to fretting wear than Zr alloys at the normal operation conditions of LWRs. [ABSTRACT FROM AUTHOR]

Diamond‐like carbon (DLC) is an amorphous material widely used in industrial applications due to its chemical, mechanical, and tribological properties and, also, for decorative purposes. However, its low adhesion to ferrous alloys reduces its effectiveness in certain applications, necessitating the use of adhesion interlayers to reduce stresses at the interfaces and enhance the density of strong bonds. In this context, the factors that promote good adhesion in this system and specify the parameters must be understood in detail. Thus, the present study aims to assess the influence of the base pressure on the deposition of an amorphous silicon carbide adhesion interlayer between DLC coating and a ferrous alloy substrate. Microstructural, physicochemical, morphological, and mechanotribological analyses were conducted to understand the adhesion behavior in terms of structural and chemical aspects. In addition to the influence of the interlayer thickness, the elemental Si/C ratios and the relative oxygen content have an impact on the maximum load supported by the coatings, as well as the different delamination mechanisms generated in adhesion tests. [ABSTRACT FROM AUTHOR]

We investigate how the magnetic state influences the interaction of Cr substitutional impurities with ½⟨111⟩ screw dislocations in bcc Fe via density functional theory (DFT). We compare the paramagnetic state, modeled with a non-collinear disordered local moment (DLM) model, with the ferromagnetic state. In a previous work [Casillas-Trujillo et al., Phys. Rev. B 102, 094420 (2020)], we have shown that the magnetic moment and atomic volume landscape around screw dislocations in the paramagnetic state of iron are substantially different from that in the ferromagnetic state. Such a difference can have an impact in the formation energies of substitutional impurities, in particular, magnetic solutes. We investigate the formation energies of Cr solutes as a function of position with respect to the screw dislocation core, the interaction of Cr atoms along the dislocation line, and the segregation profile of Cr with respect to the dislocation in paramagnetic and ferromagnetic bcc iron. Our results suggest that with increasing temperature and connected entropic effects, Cr atoms gradually increase their occupation of dislocation sites, close to twice the amount of Cr in the DLM case than in the ferromagnetic case, with possible relevance to understand mechanical properties at elevated temperatures in low-Cr ferritic steels in use as structural materials in nuclear energy applications. [ABSTRACT FROM AUTHOR]

10.1063/5.0085292 85 R. Knepper, S. Rupper, S. DeJong, M. P. Marquez, D. E. Kittell, R. L. Schmitt, and A. S. Tappan, "Investigating growth to detonation in vapor-deposited hexanitrostilbene and pentaerythritol tetranitrate films using high-throughput methods", J. Appl. Phys. Such investigations can be applied to a wide range of materials such as pure metals,[[23], [25], [27]] steels,[29] other metallic alloys[[15], [30], [32]] including additively manufactured alloys,[[34]] ceramics,[36] polymers,[37] energetic materials,[38] or nanoporous materials.[[39]] B. Equation of state and phase transitions under shock compression I In situ i x-ray diffraction (XRD) has been used to investigate the occurrence and nature of phase transitions upon shock compression at large laser facilities, synchrotron, and x-ray free electron lasers. 10.1063/5.0076869 52 P. E. Specht, W. Reinhart, and C. Scott Alexander, "Measurement of the Hugoniot and shock-induced phase transition stress in wrought 17-4 PH H1025 stainless steel", J. Appl. Phys. R. Armstrong, H. B. Radousky, R. A. Austin, O. Tschauner, S. Brown, A. E. Gleason, N. Goldman, E. Granados, P. Grivickas, N. Holtgrewe, M. P. Kroonblawd, H. J. Lee, S. Lobanov, B. Nagler, I. Nam, V. Prakapenka, C. Prescher, E. J. Reed, E. Stavrou, P. Walter, A. F. Goncharov, and J. L. Belof, "Highly ordered graphite (HOPG) to hexagonal diamond (lonsdaleite) phase transition observed on picosecond time scales using ultrafast x-ray diffraction", J. Appl. Phys. [Extracted from the article]

Introduction: As an economical and fast process method for surface modification of materials, overlay welding is increasingly widely used in the manufacturing and repair of parts in various industrial sectors. Methods: This study combines grating projection measurement to design an economical mold arc additive process, and introduces point cloud simplification algorithm for wear and repair design of the mold structure. Then, a new method for manufacturing low-cost, long-life, and economical hot stamping die inserts is designed, using low-cost forged steel and cast steel as substrates and surface welding of high-temperature alloy wear-resistant layers. Results and Discussion: The experiment shows that the proposed algorithm for simplifying scattered molds has a good evaluation effect, without any gaps, and has a good retention effect on point clouds. The maximum and minimum distances are 0.45mm and 0.025 mm, respectively. The friction coefficient of cobalt based alloys at 300°C is lower than that at 200°C, and the fluctuation period at 200°C is significantly longer than that at 300°C. HSTS steel has the highest wear resistance, and the performance of cobalt-based alloys is significantly better than that of other alloys. The compressive yield strength of iron-based alloys is the highest, and the hardness of iron-based alloys is the highest, at 53.2 HRC. Therefore, iron-based alloys were selected as a surface wear-resistant layer welding material for economical molds with cooling channels, and cobalt-based alloys were also selected as a surface wearresistant layer welding material for variable strength economical molds. The research results provide a reference for economic mold manufacturing and repair. [ABSTRACT FROM AUTHOR]

This study develops briquettes from fines generated in the processing of manganese ore from a strategic manganeferous district of Minas Gerais–Brazil. The briquettes were produced based on the following variables: compaction pressure (20 and 25MPa), curing time (7 and 28 days), percentage by mass of binder (5% and 10%), and replacement with tailings (0% and 10%). Technological tests evaluated the compressive, abrasion, impact strength and water absorption. The best conditions for briquette included 10% Portland cement, 10% Mn tailings, compaction pressure of 25MPa and 7 days of curing, as well as 10% Portland cement, compaction pressure of 25MPa and 28 days of curing. The briquettes primarily contained the spessartine, todorokite, quartz, and pyrolusite minerals. The storage time tests indicated that the briquettes responded satisfactorily to storage for three months in a dry environment and at room temperature. Through crackling tests, the briquettes have potential to be commercially used. [ABSTRACT FROM AUTHOR]

Hydrogen is a reaction product during the oxidation of alloys in steam. A fraction of the hydrogen produced diffuses into the alloy, while the remainder is released back into the gas phase. Hydrogen permeation experiments on iron and nickel foils were made to quantify the fraction of hydrogen which permeated through the metal and the fraction which went back into the gas phase. Tests were conducted at 750 °C in Ar-3% H2O on one side of the foil to track hydrogen transport during oxidation. Exposure tests at 650 and 700 °C in atmospheric pressure steam on ferritic steel T23 and ferritic/martensitic steel T92, as functions of gas velocity and sample orientation, provide evidence that the transport of hydrogen back into the gas phase influences the oxidation kinetics. Boundary layer controlled hydrogen diffusion away from the scale and into the gas phase was modelled to predict the effects of gas velocity and pressure. [ABSTRACT FROM AUTHOR]

This article provides an overview of the powder metallurgy (PM) industry in North America in 2024. The automotive market is a major driver of the industry, with a shift towards hybrid and plug-in hybrid electric vehicles (HEV and PHEV) due to environmental concerns. Lightweight metals like aluminum, magnesium, and titanium are expected to increase in use, but ferrous alloys will remain the most used due to their strength and cost-effectiveness. Other growth opportunities for PM include energy, aerospace, medical, electrical, defense, and consumer products. Metal powder shipments in 2023 decreased overall, with iron powder shipments down by over 10%. However, there is optimism for the future of PM in various industries, including AM and MIM. The P&S parts makers in the automotive industry faced challenges, but new opportunities are emerging with the shift to electric motors. The metal additive manufacturing (AM) sector is dependent on advancements in materials and manufacturing processes, with new materials and equipment being developed. Overall, the PM industry in North America is facing both challenges and opportunities in various sectors. The article also discusses the use of advanced simulation software in metal AM parts, the standard test methods issued by the Association for Metal Additive Manufacturing (AMAM), the healthy state of the metal injection molding (MIM) industry, the impact of the Russian-Ukrainian war on tungsten powder demand, and the need for investment in R&D and the development of people to advance PM technology. [Extracted from the article]

This study investigates the influence of cobalt (Co) addition on the microstructural and wear properties of an aluminum (Al) scrap alloy containing high iron (Fe) impurity content (3%). Microstructural analysis using scanning electron microscopy and optical microscopy confirmed the presence of Co in Fe-rich intermetallics. Upon increasing the Co concentration, β-Al5FeSi phase was seen to be refined without significant morphological modifications. Furthermore, Co addition promoted the formation of a new quaternary phase Al32Si7Fe4Co phase, which was finely distributed throughout the microstructure and acts as a tribo-layer in the Al scrap alloy, offering enhanced wear resistance and improved stability against wear. Standard EN-31 steel disk with compositions chromium (Cr)-1.6%, manganese (Mn)-0.75%, silicon (Si)-0.35%, and carbon (C)-0.9% was used for the wear test. Microhardness and wear properties were evaluated for both the as-cast and heat-treated alloys, with the as-cast samples exhibiting superior wear resistance and a lower coefficient of friction compared to the T6 heat-treated samples. Addition of Co showed refinement in the β-Fe rich intermetallics over the morphological modifications. Similarly, Co addition enhanced the hardness and wear resistance in the as cast alloys. This work provides a detailed analysis contributing significant understandings into the wear mechanisms and potential applications of Co modified recycled Al in various industrial sectors. [ABSTRACT FROM AUTHOR]

Comparative experimental studies have been carried out on the influence of the type and particle size distribution of the original metal granulated materials, which were used as a flux-cored wire charge, on its welding and technological properties during submerged arc surfacing. High-speed steel powder PG-R6M5 with 50-300 µm and 200-250 µm granulation, obtained by spraying of a melt metal, was used as a charge for experimental wires. The standard was flux-cored wire, the charge of which consists of ferroalloys with 50-300 µm granulation, calculated to ensure a similar chemical composition of the deposited metal and manufactured using standard technology. It has been experimentally determined that the welding and technological properties of three types of wires are at a high level, while the surfacing process with flux-cored wires, the charge of which contains granulated powder PG-R6M5, is characterized by greater stability, which results in an increase in melting and surfacing coefficients, and a decrease in the loss coefficient, compared to analogue wire with a charge of ferroalloy powders. It was also determined that the content of harmful impurities in the sample deposited with experimental wires with a charge of granulated powders is lower than in the standard sample. The patterns noted above indicate that the use of granulated powder in a fluxcored wire charge is not only technically feasible, but also leads to an increase in flux-cored wire homogeneity, which has a positive effect on their welding and technological properties. [ABSTRACT FROM AUTHOR]

One of the hottest research topics over the last decades was the valorization or/and recycling of agro-industrial wastes into different valuable liquid or solid products, which is considered a sustainable and low-cost approach. In this study, we developed zero-valent iron nanoparticles from Palm Petiole Extract (P-NZVI) using a green and straightforward approach. The as-synthesized P-NZVI was used to adsorb Cr(VI) in water. The physico-chemical characterizations of P-NZVI, including the particle size, crystalline structure, surface area, morphology, and functional groups, were investigated via several techniques such as UV-vis spectroscopy, SEM, TEM, XRD, FTIR, AFM, DLS, pHZPC measurement, and BET analysis. The adsorption performance of P-NZVI was studied under different operational parameters, including pollutant concentration, pH, temperature, and adsorbent mass. The adsorption rate was found to be 89.3% within 40 min, corresponding to the adsorption capacity of 44.47 mg/g under the following conditions: initial Cr(VI) concentration of 40 mg/L, pH 5, and a P-NZVI dosage of 1 g/L. It was found that the adsorption pattern follows the Langmuir and the pseudo-second-order kinetic models, indicating a combination of monolayer adsorption and chemisorption mechanisms. The thermodynamic study shows that the adsorption process is endothermic and spontaneous. The reusability of P-NZVI was carried out four times, showing a slight decrease from 89.3 to 87%. These findings highlight that P-NZVI's could be an effective green adsorbent for removing Cr(VI) or other types of toxic pollutants from water. [ABSTRACT FROM AUTHOR]

In this study, the effect of joint metallurgy on the mechanical performance and formability of dissimilar microplasma arc welding of austenitic steel (SS 316L) and Inconel 625 (IN 625) is represented. The welded blanks (WB) are stretched from uniaxial to biaxial by tensile test and limiting dome height test (LDH) in order to measure the joint efficiency and formability of the WBs, respectively. The joint metallurgy is characterized by transmission electron microscopy and field emission scanning electron microscopy. The results indicate that the fusion zone (FZ) consists of a homogeneous mixture of Nickel (γNi) and iron-based austenite (γFe) with different types of dendritic structure interconnected with brittle Laves phase network and some secondary phases like MC, M6C, and NbC. The presence of such phases increases the weld hardness and affects the formability of the WB. The obtained maximum elongation of the WB is 30.5%, which is 100.4% of IN 625 and 52.6% of SS 316L. Moreover, the achieved joint strength is 643.7 MPa, which is 67% of IN 625 and 94% of SS 316L. The maximum LDH of the WB, SS 316L and IN 625 is 6.7, 12.3 and 9.7 mm, respectively, in dry condition. During the tensile and LDH tests, the failure of the WB is taken place from the week partially melted zone. The thickness distribution profile of the WB shows that the thickness reduction of SS 316L side is higher than the IN 625 side. [ABSTRACT FROM AUTHOR]

Despite the historical position of the F-expansion method as a method for acquiring exact solutions to nonlinear partial differential equations (PDEs), this study highlights its superiority over alternative auxiliary equation methods. The efficacy of this method is demonstrated through its application to solve the convective–diffusive Cahn–Hilliard (cdCH) equation, describing the dynamic of the separation phase for ternary iron alloys (Fe–Cr–Mo) and (Fe–X–Cu). Significantly, this research introduces an extensive collection of exact solutions by the auxiliary equation, comprising fifty-two distinct types. Six of these are associated with Weierstrass-elliptic function solutions, while the remaining solutions are expressed in Jacobi-elliptic functions. I think it is important to emphasize that, exercising caution regarding the statement of the term 'new,' the solutions presented in this context are not entirely unprecedented. The paper examines numerous examples to substantiate this perspective. Furthermore, the study broadens its scope to include soliton-like and trigonometric-function solutions as special cases. This underscores that the antecedently obtained outcomes through the recently specific cases encompassed within the more comprehensive scope of the present findings. [ABSTRACT FROM AUTHOR]

In this work, Fe-based alloy coatings were prepared on the surface of ductile iron by laser cladding. To improve its wear resistance and consider the economic and time cost of other post-treatment processes, laser remelting was chosen to strengthen the coatings. The effect of laser remelting energy density (0−11.45 J/mm2) on the phase composition, microstructure evolution, hardness, and wear resistance of the coatings were investigated. The results show that the coating consists of γ-(Fe, Cr) and carbides and that remelting energy density has little effect on its phase composition. After remelting, the hardness uniformity of the coating was significantly improved, but increasing the remelting energy density had little effect on it. The hardness and wear resistance of the coatings were inversely related to remelting energy density. At a low remelting energy density of 5.66 J/mm2, the hardness and wear mass loss of the coating were 111.49% and 54.36% of the original coating, respectively. The mechanism for the improved hardness and wear resistance is the microstructure refinement induced by laser remelting. Increased remelting energy density reduces the microstructure refinement of the coating, but the coatings still showed good hardness and wear resistance due to the diffuse distribution of carbides at higher remelting energy density conditions of 9.43-11.45 J/mm2. [ABSTRACT FROM AUTHOR]

In this study, existing and promising methods of processing fine fractions and dust of aspiration systems for the production of ferroalloys were analyzed. The technological properties of high-carbon ferrochrome screenings and dust of the ferrochrome crushing aspiration system of the Aktobe Ferroalloy Plant as raw materials for the production of low-carbon ferrochrome briquettes using the vacuum-thermal method were studied. The contents of basic and impurity elements, including gas-forming ones, were determined. The oxygen content in the dust reached 4.2 and 0.12% in the screening. The average size of aspiration dust particles was 9.6 μm, whereas that of the ferrochrome screenings was 1.44 mm. In the dust and screening samples, the main phase was Cr7C3, and graphite was present in the dust sample. During thermal analysis, the dust sample completely melted at 1453 °C, and a liquid phase was not observed when ferrochrome was heated. At 1340 °C, the formation of iron silicide was noted. With increasing temperature, the concentrations of carbon and chromium carbide decreased. From thermodynamic calculations, recommendations were given on the parameters of vacuum-thermal decarburization of high-carbon ferrochrome. The results of preliminary experiments confirmed the possibility of removing carbon from screenings and aspiration dust. From samples containing 9.04–9.11% carbon, ferrochrome with a content of 0.10% carbon could be obtained. At the next stage of our work, we plan to work out in detail the parameters affecting the vacuum-heat treatment of ferrochrome. We assume that ferrochrome with a carbon content of 0.00x% can be obtained. [ABSTRACT FROM AUTHOR]

Iron palaeometallurgy was carried out on three artefacts, classified as nails and excavated from the archaeological site of Loiola (La Arboleda, Biscay, northern Spain), to investigate Roman manufacturing techniques. Energy Dispersive Spectroscopy (EDS) coupled with Environmental Scanning Electron Microscopy (ESEM) and micro-Raman spectroscopy were used to obtain elemental composition and structural characterization of mineral phases. Metallurgical properties and crystallographic texture were studied by combining microscopic methods such as optical microscopy (OM), Electron Backscatter Diffraction realized in environmental mode (EBSD) and measurements of local Vickers microhardness. The three artefacts had different microstructures, distinguished by a large gradient of carbon content, although important segregations (inclusions) were observed in all of them. Two pearlite-rich artefacts showed a high density of structural defects (geometrically necessary dislocations and large crystallographic orientation gradients in pearlitic ferrite, curved pearlitic cementite) resulting from a high level of plastic deformation that occurred during the manufacturing process. The third artefact consisted of pure ferrite without structural defects. This one was clearly manufactured differently from the two others, so it probably had another functionality. [ABSTRACT FROM AUTHOR]

SiMo ductile cast iron combines ease of part fabrication with good mechanical properties, including a usable plasticity range. Its poor corrosion resistance inherited from grey cast iron could be alleviated through alloying with Al or Cr additions capable of forming a dense oxide scale protecting the substrate. However, the presence of Al and Cr in cast iron tends to make the material brittle, and their optimum alloying additions need to be studied further. The present work was aimed at investigating the effect of crystallization rates on microstructure changes during directional crystallization of SiMo-type alloys with up to 3.5% Al and 2.4% Cr. The experiment was performed using the Bridgman–Stockbarger method. The tubular crucible was transferred from the hot section to cold section at rates ranging from 5 mm/h to 30 mm/h with a 4/5 crucible length and then quenched. The introduced Al promoted graphitization up to a point, wherein, at the highest applied addition, the graphite precipitation preceded crystallization of the rest of the melt. A rising level of Cr in these alloys from 1% to 2.4% resulted in the formation of low and high contents of pearlite, respectively. The higher crystallization rates proved effective in increasing the ferrite content at the expense of pearlite. In the investigated cast iron samples with smaller applied alloying additions, Widmanstätten ferrite or ausferrite, i.e., fine acircular phase, were often found. The switch from directional crystallization to quenching caused a transition from a liquid to solid state, which started with nucleation of islands of fine austenite dendrites with chunky graphite eutectic separating them. As these islands expanded, they pushed alloying additions to their sides, promoting carbide or pearlite formation in these places and forming a super-cell-like structure. The performed experiments helped gather information concerning the sensitivity of the microstructure of SiMo cast iron modified with Al and Cr to crystallization rates prevailing in heavy cast structures. [ABSTRACT FROM AUTHOR]

In differentiated planetesimals, the liquid core starts to crystallize during secular cooling, followed by the separation of liquid–solid phases in the core. The wetting property between liquid and solid iron alloys determines whether the core melts are trapped in the solid core or they can separate from the solid core during core crystallization. In this study, we performed high‐pressure experiments under the conditions of the interior of small bodies (0.5–3.0 GPa) to study the wetting property (dihedral angle) between solid Fe and liquid Fe‐S as a function of pressure and duration. The measured dihedral angles are approximately constant after 2 h and decrease with increasing pressure. The dihedral angles range from 30° to 48°, which are below the percolation threshold of 60° at 0.5–3.0 GPa. The oxygen content in the melt decreases with increasing pressure and there are strong positive correlations between the S + O or O content and the dihedral angle. Therefore, the change in the dihedral angle is likely controlled by the O content of the Fe‐S melt, and the dihedral angle tends to decrease with decreasing O content in the Fe‐S melt. Consequently, the Fe‐S melt can form interconnected networks in the solid core. In the obtained range of the dihedral angle, a certain amount of the Fe‐S melt can stably coexist with solid Fe, which would correspond to the "trapped melt" in iron meteorites. Excess amounts of the melt would migrate from the solid core over a long period of core crystallization in planetesimals. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of High Pressure Physics is the property of Chinese Journal of High Pressure Physics 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.)

Aluminum-oxygen equilibria for varying concentration of aluminum (0.0008–23.35 wt pct) content have been established at 1873 K. The experiments were carried out in an inert (high-purity argon) atmosphere by melting pure electrolytic iron with master alloy of Fe-Al in an alumina crucible and equilibrating the Fe-Al-O melt at 1873 K for two hours. A two-stage heating method in an inert gas fusion absorptiometry and scanning electron microscopy-automated inclusion analysis (SEM-AIA) have been employed to estimate the insoluble oxygen content in the samples. Aluminum-oxygen equilibria have been established separately for the total and dissolved oxygen contents. Thermodynamic analysis has been carried out using higher order interaction parameters, namely, Wagner interaction parameter formalism (WIPF) truncated at 2nd order, Darken's quadratic formalism, and the Cubic formalism. Among these formalisms, the experimental analysis has been found to be in good agreement with thermodynamic analysis based on Cubic formalism. [ABSTRACT FROM AUTHOR]

Conventional powder metallurgy processes are often associated with poor strength due to the presence of porosity. Warm die compaction methods have been shown to be effective in reducing porosity while also being highly economical. This study investigated the impact of warm die compaction behavior on the sintered mechanical properties of iron-based PM. Iron-based alloys were fabricated using four types of powders, namely ASTALOY CRA, ASTALOY 85Mo, DISTROY AE, and DISTROY AQ, by compacting them under different compacting pressure using both warm die compaction at a temperature of 90 °C and cold die compaction at room temperature. The findings revealed that warm die compaction at 90 °C exhibited superior ejection performance relative to compaction at room temperature. The green density increased by 0.01-0.1 g/cm3, and the green strength improved by 2.68-8.25 MPa. The hardness, tensile strength, and yield strength of the sintered specimens fabricated by warm die compaction were improved by 0.25-0.94%, 2.23-7.08%, and 1.23-13.23%, respectively. [ABSTRACT FROM AUTHOR]

This paper presents the effect of the complex strain state resulting from the asymmetric rolling of TRB products on the changes and distribution of the stress state in the material. The evaluation of the stress state in the material was based on measurements of the magnetoelastic parameter (MP) using the Barkhausen magnetic noise method. The key characteristics of the material under study that enabled the use of changes in the MP parameter to assess the stress state were ferromagnetism and a lack of texture. The first of these enabled the detection of the magnetic signals produced when a magnetic field is applied to the material, causing magnetic domains to align and sudden changes in magnetization. On the other hand, the absence of texture in the material precluded the occurrence of magnetocrystalline anisotropy, which could disturb the results of measurements of the magnetoelastic parameter in the material. In order to determine these features in the material under study, its chemical composition was determined, and a phase analysis was carried out using the X-ray diffraction method. The results of these tests showed the possibility of determining the stress state of the material by means of changes in the values of the MP parameter. On this basis, it was shown that in the TRB strips studied, there is a complex state of stress, the values of which and the nature of the changes depending on the direction of the measurements carried out, as well as on the amount of rolling reduction in the studied area of the strip. [ABSTRACT FROM AUTHOR]

The effectiveness of transformation‐induced plasticity (TRIP)/twinning‐induced plasticity (TWIP) effects in Fe–0.06C–26Mn–3Si–3Al advanced ferrous alloy is analyzed over a wide temperature range of −40 to 200 °C. The specific deformation mechanisms in the steel are experimentally investigated and predicted using thermodynamic calculations of stacking fault energy (SFE). These predictions were correlated with the microstructure of the steel and its mechanical behavior. The study finds that applied thermodynamic models effectively predict the occurrence of TRIP/TWIP effects at different deformation temperatures, aligning well with experimental observations in terms of ε/α′ martensite formation, indicative of the TRIP mechanism. Some discrepancies in SFE results are observed at Mn contents significantly higher or lower than the nominal composition of steel. [ABSTRACT FROM AUTHOR]

While the density of materials is important for their mechanical and service properties, it is striking that so little is known in the case of silicon cast irons, which are essentially Fe–C–Si alloys with graphite precipitates in an iron-rich matrix. In this work, a review of literature data was used to establish an expression for the lattice parameter of ferrite based on that of pure iron, to which were added the individual effects of carbon, silicon, manganese, phosphorus, and copper. The expression thus obtained is valid for a homogeneous material, and a correction is proposed to take into account of the presence of graphite in Fe–C–Si ferritic alloys. Next, the ferrite lattice parameter of a series of 12 alloys containing carbon between 1.0 and 4.1 wt pct, silicon between 0.5 and 4.3 wt pct, up to 0.7 wt pct Mn and up to 0.9 wt pct Cu, was measured by XRD from room temperature to a temperature of 1150 °C. These recordings showed that the mirror polishing used to prepare the samples resulted in surface alteration and a significant overestimation of the ferrite lattice parameter for temperatures below 500 °C. We therefore carried out high-energy XRD at room temperature, which was free of any surface effects and validated our analysis. Valid measurements at room temperature and XRD values obtained at temperatures above 500 °C were then successfully compared with the predictions given by the proposed expression for the lattice parameter of ferrite as a function of temperature and alloying elements. This work provides the necessary information to calculate the theoretical density of ferritic cast irons. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology Journal is the property of Springer Nature 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.)

As promising energy-storage devices, zinc–air batteries (ZABs) exhibit slow reaction kinetics for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) occurring at their electrodes. High-performance bifunctional catalysts must thus be synthesized to accelerate the reversible conversion of oxygen and improve the rate and overall performance of ZABs. Herein, we reported the promising prospects of self-supported composite electrodes composed of wood-derived carbon (WDC) and bimetallic cobalt-iron alloys/oxides (CoFe-CoFe2O4@WDC) as efficient electrocatalysts for alkaline ORR/OER. WDC provided a favorable three-phase interface for heterogeneous reactions owing to its layered porous structure and genetic stability, thereby enabling mass diffusion and improving reaction kinetics. The CoFe2O4 spinel surface was reduced to bimetallic CoFe alloy to form abundant heterostructure interfaces that promote electron transfer. Under alkaline conditions, the optimized composite electrode exhibited a remarkable high half-wave potential of 0.85 V and an exceptionally low overpotential of 1.49 V. It also exhibited stable performance over an impressive 2340 cycles in a ZAB. Theoretical calculations also confirmed that the heterointerface addresses the issue of proton scarcity throughout the reaction and actively facilitates the creation of O–O bonds during the reversible transformation of oxygen. This study introduces a new concept for developing bifunctional and efficient electrocatalysts based on charcoal and encourages the sustainable and high-value use of forest biomass resources. Highlights: Water dissociation was regulated to provide proton for smooth response under alkaline conditions and accelerate the conversion of *O2 to *OOH. The alloy surface formed CoFe oxyhydroxide in the OER voltage range, and the adsorption capacity of intermediates was adjusted to facilitate O–O bond formation. The d-band center moved downward due to interface electron interaction, modifying the binding ability of intermediates. [ABSTRACT FROM AUTHOR]

An organic–inorganic hybrid is a promising electrode material for aqueous batteries due to its larger potential in improving electrochemical performance. Herein, we designed and prepared a naphthoquinone@FeOx(OH)/iron foam (NQ@FeOx(OH)/IF) hybrid electrode as a highly-efficient anode in Ni/Fe batteries via combining electro-deposition of FeOx(OH) and in situ hydrothermal growth of naphthoquinone. The as-prepared hybrid electrode materials present a 2D nanosheet morphology of FeOx(OH) and a branch/band-like structure of NQ, with the formation of NQ–FeOx(OH) interfaces. Such an interface structure is revealed to have more electron active sites, with increased electron delocalization caused by the aromatic ring structure, thereby enhancing the transport of the electrons in the electrode materials. Thus, a superior electrochemical performance of the NQ@FeOx(OH)/IF electrode was received, with a large areal capacity of ∼2.23 mA h cm−2 and a favorable rate capability of 1.09 mA h cm−2 at 40 mA cm−2. Besides, the NQ@FeOx(OH)/IF anode was coupled with the NiCo2O4 cathode to assemble a Ni/Fe battery, as a result, an admirable energy density of 235.2 W h kg−1 and a maximum power density of 5.4 kW kg−1 were obtained. The study on high-performance NQ@FeOx(OH)/IF electrode materials paves the way to design and synthesize better iron-based materials for Ni/Fe batteries. [ABSTRACT FROM AUTHOR]

This study aimed at characterizing some properties of an Fe-Al alloy obtained from a congruent melt within 53–57 wt.% composition range. It focused on checking the homogeneity and uniqueness of the constituent's phase. Different analyses and examination techniques were used to explore and assess these properties. The obtained results were compared with those published in the literature. The obtained compound was also submitted to a verification for its homogeneity and phase uniqueness. The main results showed that the obtained alloy has a measured density similar to that reported in the literature. The water immersion method was used. Furthermore, the global and local chemical composition obtained by x-ray fluorescence (XRF) and scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS), respectively, are in agreement with the concentration range of the η Fe2Al5 stoichiometric compound. Analysis by Differential Thermal Analysis (DTA) showed that the alloy exhibits a single transformation peak during solidification, which testifies that the phase is unique. The latter exhibits a melting temperature that is identical to that mentioned by many authors. This result is in agreement with the one obtained by x-ray diffraction (XRD) analysis, attesting again that the phase is unique. The typical quadrupole doublet of an Al-rich paramagnetic material in the case of two different environments is represented by Mössbauer spectra. It corresponds to single-phase disordered solid solutions with a η-Fe2Al5 crystal structure. On the other hand, the measured hardness for the studied alloy reaches 912 Hv, which attests of its fragility and its grindability. This last result is supported by the SEM fracture surface analysis, which reveals an intergranular fracture of the brittle type. [ABSTRACT FROM AUTHOR]

Coffee is the most popular beverage after water in the world, which has an important role in health as a result of various minerals and vitamins but it may be pollution source of potentially toxic elements (PTEs) that can threate the health. Thus, the current study intended to detect the level of PTEs such as Cadmium (Cd), Copper (Cu), Lead (Pb), Nickel (Ni), Znc (Zn) and Iron (Fe), in various coffee and coffee-based products (powder, ground, processed, infusion and bean). Considering the databases of Scopus, Google scholar, PubMed, and Web of Science, the concentration of PTEs in coffee and coffee-based products was retrieved and meta-analyzed. Additionally, the non-carcinogenic risks in terms of total hazard quotient (TTHQ) were assessed using Monte Carlo simulated (MCS) model. According to the findings of 23 articles, the ranking of metal concentration in different coffees was Fe > Zn > Cu> Ni > Pb > Cd in powder, Fe > Cu > Zn> Ni in ground, Fe > Zn > Ni> Cu> Pb > Cd in processed and infusion and Fe > Zn > Ni> Cs > Pb in bean. Moreover, based on WHO regions, the highest concentrations of Cd and Pb (0.742 mg/kg) were related to the South-East Asia Region (SEARO) and European region (EURO) respectively. However, the highest concentrations of Fe (81.161 mg/kg), Zn (33.392 mg/kg), Cu (9.408 mg/kg), and Ni (18.064 mg/kg) were related to Pan American health organization (PAHO), PAHO, PAHO and Eastern Mediterranean Region (EMRO), respectively. On the other hand, the risk pattern was different in different countries. Moreover, consumers in some countries were not at significant non-carcinogenic risks because of ingestion of PTEs via coffee and consumption of coffee-based products. [ABSTRACT FROM AUTHOR]

Metallic bioresorbable orthopaedic implants based on magnesium, iron and zinc-based alloys that provide rigid internal fixation without foreign-body complications associated with permanent implants have great potential as next-generation orthopaedic devices. Magnesium (Mg) based alloys exhibit excellent biocompatibility. However, the mechanical performance of such implants for orthopaedic applications is contingent on limiting the rate of corrosion in vivo throughout the bone healing process. Additionally, the surgical procedure for the implantation of internal bone fixation devices may impart plastic deformation to the device, potentially altering the corrosion rate of the device. The primary objective of this study was to develop a computer-based model for predicting the in vivo corrosion behaviour of implants manufactured from a Mg-1Zn-0.25Ca ternary alloy (ZX10). The proposed corrosion model was calibrated with an extensive range of mechanical and in vitro corrosion testing. Finally, the model was validated by comparing the in vivo corrosion performance of the implants during preliminary animal testing with the corrosion performance predicted by the model. The proposed model accurately predicts the in vitro corrosion rate, while overestimating the in vivo corrosion rate of ZX10 implants. Overall, the model provides a "first-line of design" for the development of new bioresorbable Mg-based orthopaedic devices. Biodegradable metallic orthopaedic implant devices have emerged as a potential alternative to permanent implants, although successful adoption is contingent on achieving an acceptable degradation profile. A reliable computational method for accurately estimating the rate of biodegradation in vivo would greatly accelerate the development of resorbable orthopaedic implants by highlighting the potential risk of premature implant failure at an early stage of the device development. Phenomenological corrosion modelling approach is a promising computational tool for predicting the biodegradation of implants. However, the validity of the models for predicting the in vivo biodegradation of Mg alloys is yet to be determined. Present study investigates the validity of the phenomenological modelling approach for simulating the biodegradation of resorbable metallic orthopaedic implants by using a porcine model that targets craniofacial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

This study reports on the magnetic hardening phenomenon of heavily helium ion-irradiated iron–chromium alloys. The alloys are important structural materials in next-generation nuclear reactors. In some cases, problems may arise when the magnetic properties of the materials change due to neutron irradiation. Therefore, it is necessary to understand the effects of irradiation on magnetism. Helium irradiation was conducted as a simulated irradiation, and the effect of cavity formation on magnetic properties was thoroughly investigated. High-quality single-crystal Fe-x%Cr (x = 0, 10, 20) films, with a thickness of 180–200 nm, were fabricated through ultra-high vacuum evaporation. Subsequently, irradiation of 19 dpa with 30 keV He+ ions was conducted at room temperature. X-ray diffraction measurements and electron microscopy observations confirmed significant lattice expansion and the formation of high-density cavities after irradiation. The magnetization curve of pure iron remained unchanged, while magnetic hardening was noticed in iron–chromium alloys. This phenomenon is believed to be due to the combined effect of cavity formation and changes in the atomic arrangement of chromium. [ABSTRACT FROM AUTHOR]

This paper deals with the possibility of smelting quasi-high-entropy alloys (QHEAs) with the partial use of ferroalloys in the charge instead of pure metals. The Cantor alloy (CoCrFeMnNi) was used as the base alloy and the comparison sample, into which niobium was introduced in the amount of 14 to 18% by weight. The structure, hardness, strength, and tribological properties of prototypes were studied. The results obtained showed, on the one hand, the possibility of using ferroalloys as charge components in the smelting of QHEAs and, on the other hand, the positive effect of niobium in the amount of 14–17% on the strength and wear resistance of the alloy. Increasing the niobium content above 18% leads to its uneven distribution in the structure, consequently decreasing the strength and wear resistance of the alloy. The structure of the studied alloys is represented by a solid solution of FCC, which includes all metals, and the niobium content varies widely. In addition, the structure is represented by the phases of implementation: niobium carbide NbC 0.76–1.0, manganese carbide Mn7C3, and a CrNi intermetallic compound with a cubic lattice. [ABSTRACT FROM AUTHOR]

The performance and quality of steel products are significantly impacted by the alloying element control. The efficiency of alloy utilization in the steelmaking process was directly related to element yield. This study analyses the factors that influence the yield of elements in the steelmaking process using correlation analysis. A yield prediction model was developed using a t-distributed stochastic neighbor embedding (t-SNE) algorithm, a whale optimization algorithm (WOA), and a long short-term memory (LSTM) neural network. The t-SNE algorithm was used to reduce the dimensionality of the original data, while the WOA optimization algorithm was employed to optimize the hyperparameters of the LSTM neural network. The t-SNE-WOA-LSTM model accurately predicted the yield of Mn and Si elements with hit rates of 71.67%, 96.67%, and 99.17% and 57.50%, 89.17%, and 97.50%, respectively, falling within the error range of ±1%, ±2%, and ±3% for Mn and ±1%, ±3%, and ±5% for Si. The results demonstrate that the t-SNE-WOA-LSTM model outperforms the backpropagation (BP), LSTM, and WOA-LSTM models in terms of prediction accuracy. The model was applied to actual production in a Chinese plant. The actual performance of the industrial application is within a ±3% error range, with an accuracy of 100%. Furthermore, the elemental yield predicted by the model and then added the ferroalloys resulted in a reduction in the elemental content of the product by 0.017%. The model enables accurate prediction of alloying element yields and was effectively applied in industrial production. [ABSTRACT FROM AUTHOR]