Modern Materials Science Research Articles

Phase prediction in high-entropy alloys with multi-label artificial neural network

The prediction of phase composition in metallic alloys is one of the main challenges in modern material science. The most effective and promising methods to solve this problem are currently based on machine learning (ML) algorithms. The most urgent issues in developing such methods are the choice of input features (descriptors) and the search for the most effective ML models. Here we address these issues for the problem of phase composition prediction in high-entropy alloys (HEAs). We combine two ideas recently proposed in this field: the use of genetic algorithms to search for optimal sets of descriptors and a multi-label classification scheme. By using this approach, we achieve the value of balanced accuracy of more than 91% in the prediction of selected phases.

Obtaining functional-gradient Ti-HA coatings by detonation spraying

Functional-gradient titanium/hydroxyapatite (TiHA) coatings were obtained using detonation spraying technology to improve the structure and mechanical properties. To obtain functional-gradient coatings, pulsed energy sources are best suited, namely, detonation spraying, in which the energy of the explosion of gas mixtures is used as a source of pulsed action. By controlling the modes of detonation spraying, it is possible to vary the temperature and rate of coating deposition; accordingly, it is possible to obtain a certain structuralphase structure of the coatings. The structural-phase state and tribological properties of TiHA detonation coatings were investigated by modern materials science methods: X-ray phase analysis (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX-mapping), profilometry and ball-disk wear-resistance test. The results showed that the coatings had a continuously gradient elemental composition across the cross-section of the coatings with no boundary between the elemental layers of the coatings. The amount of Ti gradually decreased and the amount of hydroxyapatite gradually increased in the direction from the substrate to the surface of the coatings, which allows to expand the possibilities of using TiHA-coatings for bone implants. Since the surface layer is composed of HA, the resulting functional-gradient coating demonstrates excellent biocompatibility and the ability to create new bone tissue. The excellent mechanical strength of the functionally graded coatings is ensured by the Ti phase.

Significance of nanoparticles aggregation on the dynamics of rotating nanofluid subject to gyrotactic microorganisms, and Lorentz force

The significance of nanoparticle aggregation, Lorentz and Coriolis forces on the dynamics of spinning silver nanofluid flow past a continuously stretched surface is prime significance in modern technology, material sciences, electronics, and heat exchangers. To improve nanoparticles stability, the gyrotactic microorganisms is consider to maintain the stability and avoid possible sedimentation. The goal of this report is to propose a model of nanoparticles aggregation characteristics, which is responsible to effectively state the nanofluid viscosity and thermal conductivity. The implementation of the similarity transforQ1m to a mathematical model relying on normal conservation principles yields a related set of partial differential equations. A well-known computational scheme the FEM is employed to resolve the partial equations implemented in MATLAB. It is seen that when the effect of nanoparticles aggregation is considered, the temperature distribution is enhanced because of aggregation, but the magnitude of velocities is lower. Thus, showing the significance impact of aggregates as well as demonstrating themselves as helpful theoretical tool in future bioengineering and industrial applications.

Computational prediction of new magnetic materials.

The discovery of new magnetic materials is a big challenge in the field of modern materials science. We report the development of a new extension of the evolutionary algorithm USPEX, enabling the search for half-metals (materials that are metallic only in one spin channel) and hard magnetic materials. First, we enabled the simultaneous optimization of stoichiometries, crystal structures, and magnetic structures of stable phases. Second, we developed a new fitness function for half-metallic materials that can be used for predicting half-metals through an evolutionary algorithm. We used this extended technique to predict new, potentially hard magnets and rediscover known half-metals. In total, we report five promising hard magnets with high energy product (|BH|MAX), anisotropy field (Ha), and magnetic hardness (κ) and a few half-metal phases in the Cr-O system. A comparison of our predictions with experimental results, including the synthesis of a newly predicted antiferromagnetic material (WMnB2), shows the robustness of our technique.

Structural Formation of Alkali-Activated Materials Based on Thermally Treated Marl and Na2SiO3.

Modern materials science is aimed towards abandoning Portland cement in the production of building materials. The scientific novelty of this study lies in its being the first time a comprehensive study of the structure formation of alkali-activated materials (AAM) based on thermally treated marl and Na2SiO3 is carried out. The tasks for achieving this goal were to characterize the thermally treated marl as a new binder, and to comprehensively research the microstructure, fresh, physical, and mechanical properties of the AAM based on the binder. Received active particles of marl with a smaller size than Portland cement have a specific surface area of 580–590 m2/kg. The mineral composition of heat-treated marl is characterized by calcium silicates, which guarantee good binding properties. The results of X-ray diffraction analysis of the samples based on the clinker-free binder of alkaline activation using opoka-like marl confirmed the presence of calcite, quartz, and feldspar close to albite, micas, and zeolites. The obtained products of the chemical interaction of the components of the binder confirm the effectiveness of the newly developed AAM. As a result of comparing several binders, it was found that the binder “thermally treated marl—Na2SiO3” is the most effective, since for specimens based on it, a maximum compressive strength of 42.6 MPa, a flexural strength of 4.6 MPa, and minimum setting time were obtained (start 26 min, end 32 min) as well as a water absorption of 10.2 wt.%. The research results will be of interest to specialists in the construction industry, since the proposed recipes for clinker-free cements are an alternative to expensive and energy-intensive Portland cement and provide the creation of strong and durable concrete and reinforced concrete composites.

Direct conversion of methane to zeolite-templated carbons, light hydrocarbons, and hydrogen

Efficient direct valorization of methane to value-added chemicals and materials remains an unsolved challenge for modern chemistry and materials science. In this work, we explored direct non-oxidative conversion of methane to hydrogen, hydrocarbons, and valuable zeolite-templated carbon materials. First, using a set of spectroscopy and microscopy characterization tools, we investigated how the reaction conditions influence the process of carbon formation inside the typical zeolite-based catalyst Mo/ZSM-5. Then, we explored the effect of the zeolite topology on the growth of carbon materials from methane decomposition over Mo/MFI, Mo/MOR, Mo/BEA, and Mo/FAU templates. Finally, we applied the obtained insights to prepare high-quality zeolite-templated carbons directly from methane using Fe/BEA and Fe/FAU templates. Altogether, our results represent a carbon-economic method of methane conversion to COx-free hydrogen gas, a mixture of light aliphatic and aromatic hydrocarbons, and valuable carbon materials.

Significance of SWCNTs and MWCNTs on the dynamics of hybrid nanofluid flow over a stretching surface

In this article, the hybrid nanofluid flow across the hot substrate of a heated sink coated with an open-cell metallic foam is explored to increase the rate of heat transfer. Two sorts of nanoparticles are considered to be specific MWCNT and SWCNT taking water as the base liquid. Tiny particles are examined because of their remarkable properties, such as exceptional thermal conductance, which is important in modern nano-technology, cooling systems, material sciences, and electronic parts. The primary goal of this extensive study is to improve heat transportation. The mathematical equations for the considered flow are the Navier–Stokes equations in the form of the Darcy–Brinkman–Forchheirmer model. Using similarity variables, a system of PDEs is converted into a system of dimensionless ODEs. The subsequent ODEs are settled by utilizing the numerical technique bvp4c in MATLAB. The significant results are presented with the guide of figures and tables. From this analysis, it is observed that the Xue model has a larger heat transport rate than the Yamada–Ota and Tiwari–Das models. Furthermore, the Xue model achieves a higher skin friction coefficient and Nusselt number values than the Yamada–Ota and Tiwari–Das models.

Study on the difference in adsorption performance of graphene oxide and carboxylated graphene oxide for Cu(II), Pb(II) respectively and mechanism analysis

Graphene oxide has been widely studied as a new type of adsorbent due to its strong affinity for heavy metal ions. However, limited by the number of oxygen-containing functional groups on its surface, there are still some defects in the field of heavy metal ion adsorption. In this paper, graphene oxide (GO) was prepared by modified Hummers method, and carboxylated graphene oxide (GO-COOH) was further synthesized by the derivatization reaction of bromoacetic acid with hydroxyl group under strong alkali conditions. The physical and chemical properties of the material were characterized by XRD, SEM, TEM, XPS and FT-IR. Taking copper and lead ion solutions as pollution models, the adsorption behaviors of the two heavy metal ions solutions on GO were investigated through batch adsorption experiments, adsorption kinetic model, adsorption isotherm model and Van't Hoff equation. The experimental results showed that the maximum adsorption capacity of GO for Cu(II) after carboxyl group treatment increased from 55.47 mg/g to 62.02 mg/g, and the maximum adsorption capacity of GO-COOH for Pb(II) increased from 85.17 mg/g to 96.21 mg/g. In this paper, the reasons for the difference in the adsorption capacity of GO for Cu(II) and Pb(II) and the significant enhancement of the adsorption performance of GO-COOH were discussed, and the possible adsorption mechanism was proposed. The research in this paper provides a new way to realize the efficient utilization of graphene oxide materials in the purification process of water environment and the development of modern materials science.

Development and Physio-Mechanical Characterization of Sustainable Jute-Wood Dust Reinforced Hybrid Composites

ABSTRACT Composite materials are the subject of modern material science developments. It’s been employed in a variety of real-world scenarios. Researchers have increasingly focused on natural fibers in composite materials because of its long-term influence and environmental concern. Conversion of waste into useful product is something the researchers are concentrating upon nowadays. The present work deals with Physio-Mechanical characterization of the sustainable jute and wood dust reinforced polymer matrix composite (PMC). The proposed composites are prepared using hand layup technique in five different combinations of compositions. The results exhibited better physio-mechanical properties and showed that optimum addition of wood dust is 30 wt% for obtaining improved mechanical properties of proposed composites. These proposed composites are found to be suitable for internal constructions such as partition walls at low cost.

A system for analyzing abnormal physico-mechanical properties and processability of non-ferrous alloys based on equilibrium diagrams

The database of modern materials science contains numerous empirical equilibrium diagrams (state diagrams) of non-ferrous alloys, with the help of which one can predict possible interactions of the components based on different ratios and temperatures and also get an insight into the phase composition and structure of these alloys. In general, there exists a good correlation between the structure and properties of non-ferrous alloys, which can help control their properties and predict possible changes. However, in certain cases, the relationship between actual physico-mechanical properties and processability of non-ferrous alloys established through experiments and their structure may deviate from the established trend. This makes it harder to control the properties and predict how they will possibly change during manufacturing and operation of machine building materials. Having looked at a great amount of data from the literature, the authors developed a system that helps analyze relationships between abnormal physicomechanical properties and processability of non-ferrous metals (Cu – Zn, Cu – Sn, Cu – Mn, Al – Si, Al – Cu, Al – Zn, Al – Mg, Mg – Al, Pb – Sb, Pb – Zn, Cd – Pb, Sn – Pb, Sn – Bi, Sn – Zn, Sn – Al) and their equilibrium diagrams. The system enables to relate abnormal properties of alloys to equilibrium diagrams using the criterion К , which reflects a qualitative change (temperature-based length) of the crystallization (recrystallization) interval. It also helps relate abnormal properties of alloys to the different structural heredity (genealogy) of atoms constituting the binary components, explain the existing abnormal properties and predict them by looking at equilibrium diagrams.

Structure and properties of high-entropy FeCoCrNiAl alloy coating

The coating of a high-entropy alloy (HEA) of non-equiatomic composition was formed on a substrate of alloy 5083 using the technology of wire-arc additive manufacturing (WAAM) in an atmosphere of pure nitrogen. Analysis of the structure, elemental composition, micro-hardness, and wear resistance of the coating/substrate system was carried out using the methods of modern physical materials science.

Practical quantum advantage in quantum simulation.

The development of quantum computing across several technologies and platforms has reached the point of having an advantage over classical computers for an artificial problem, a point known as 'quantum advantage'. As a next step along the development of this technology, it is now important to discuss 'practical quantum advantage', the point at which quantum devices will solve problems of practical interest that are not tractable for traditional supercomputers. Many of the most promising short-term applications of quantum computers fall under the umbrella of quantum simulation: modelling the quantum properties of microscopic particles that are directly relevant to modern materials science, high-energy physics and quantum chemistry. This would impact several important real-world applications, such as developing materials for batteries, industrial catalysis or nitrogen fixing. Much as aerodynamics can be studied either through simulations on a digital computer or in a wind tunnel, quantum simulation can be performed not only on future fault-tolerant digital quantum computers but also already today through special-purpose analogue quantum simulators. Here we overview the state of the art and future perspectives for quantum simulation, arguing that a first practical quantum advantage already exists in the case of specialized applications of analogue devices, and that fully digital devices open a full range of applications but require further development of fault-tolerant hardware. Hybrid digital-analogue devices that exist today already promise substantial flexibility in near-term applications.

THERMODYNAMIC ANALYSIS OF THE CHEMICAL RESISTANCE OF CERAMIC MATERIALS IN THE RO- Al2O3-SiO2 SYSTEM

Operational characteristics, properties of modern aircraft and aerospace devices and their technical characteristics owe a lot to the radio engineering systems that are installed on them. Therefore, their protection and the selection of the necessary ceramic material, which will ensure the protection of electronic devices from interaction with the external environment, is an important task of modern materials science.
 In order to substantiate the choice of a crystalline phase as the basis of a radio-transparent ceramic material that will be used in aggressive environments, it is advisable to conduct thermodynamic calculations, namely changes in the Gibbs free energy of chemical reactions of the interaction of the crystalline phase with an aggressive environment. To carry out thermodynamic calculations of chemical stability reactions, the three-component system RO- Al2O3-SiO2 (RО – SrО, BaО) was chosen and the crystalline phases that can exist within them were determined. When choosing experimental crystalline phases, a complex of physico-chemical and operational requirements for radio-transparent materials was taken into account. From the point of view of thermodynamics, the corrosion behavior of the selected crystalline phases: celsian BaO·Al2O3·2SiO2, slavsonite SrO·Al2O3·SiO2, SrO·SiO2, and 2SrO·SiO2 is considered.
 The paper presents the results of thermodynamic calculations of changes in enthalpy, entropy, and Gibbs free energy of reactions to determine acid resistance (HСl, H2SO4, HNO3) and alkali resistance (NaОН, Na2CO3) of these compounds under standard conditions. It was established that all considered compounds have a thermodynamic probability of corrosion resistance to the action of alkaline reagents. In relation to an acidic environment, under normal conditions, celsian and slavsonite show acid resistance to hydrochloric acid, and they are least prone to interaction with sulfuric acid, but are able to actively interact with HNO3. Regarding the investigated binary compounds SrO·SiO2 and 2SrO·SiO2, all calculated reactions are thermodynamically favorable, i.e. interaction with acidic reagents occurs.
 The obtained results are analyzed and the correlation of the calculations of the reaction of celsian and hydrochloric acid with experimental data is given. It was concluded that it is rational to plan the production of ceramic products based on celsian and slavsonite or their heterophase mixture with a minimum content of binary oxides of strontium and barium.

THERAPEUTIC PROPERTIES OF CAPSAICIN: A MEDICINALLY IMPORTANT BIO-ACTIVE CONSTITUENT OF CHILLI PEPPER

Plants are the source of numerous pharmaceutically important compounds that have been employed to cure various human ailments since ancient times. With the assistance of modern chemistry and materials science, such pharmaceutically important compounds have been identified and isolated to produce new drugs. Alkaloids are one of the most significant classes of naturally occurring secondary-metabolites, which are synthesized and widely distributed in various parts of plants. They regulate various metabolic activities and induce physiological responses in the human body. Capsaicin is a naturally occurring alkaloid found in many species of peppers and is attributed to their spicy nature and pungent flavor. This alkaloid is a member of the Capsaicinoids group, which includes capsaicin, homocapsaicin, homodihydrocapsaicin, dihydrocapsaicin, and nordihydrocapsaicin. Capsaicin has a wide range of therapeutic potential against various human ailments. In this article, we provide a comprehensive overview of the capsaicin molecule as well as an examination of its medicinal properties in a variety of human disorders, including pain, various types of cancer, ulcers, diabetes, obesity, inflammation, cardiovascular diseases, and neurodegenerative diseases.

Properties of Steel Modified by Surface Ion Implantation with Mo, Ti, and Al

Modification of metals by a surface treatment is one of the first problems of modern materials science. The use of ion-plasma technologies for a modification of initial specimens, in particular, by ion implantation, for this purpose can be considered a promising solution. We study the microstructure, phase and elemental compositions, wetting forces, and electrical properties of steel with implanted ions of titanium, aluminum, and molybdenum. The results obtained by means of XRD, XPS, optical microscopy, and laboratory experiments show significant differences between the treated and untreated specimens. The modification of metal by ion implantation causes changes in the wettability and electrical characteristics and indicates the prospects of this technology for mechanical engineering, chemical, food, pharmaceutical industries, for the construction of structures and vehicles, including their work under severe atmospheric conditions.

Formulation and characterization of Wrightia Tinctoria loaded zinc oxide nanoparticles by green synthesis

In the recent years, nanotechnology has become an important research field of modern material sciences. Green synthesis has garnered wide interest due to its inherent features like rapidity, eco-friendly and cost effectiveness. Zinc oxide nanoparticles were synthesized using Wrightia Tinctoria leaf extract using sol-gel method. The formation of Zinc oxide nanoparticles is confirmed by FTIR. The characterization of the formulated nanoparticles was done by X-ray diffraction (XRD) studies showed the crystalline nature and revealed the purity of Zinc oxide nanoparticles. The morphological studies Transmission electron microscopic (TEM) the shape of the nanoparticles can be identified. The zinc oxide nanoparticles were found to be rod-shaped on Scanning Electron Microscopy (SEM). The in-vitro antibacterial activity showed that the Wrightia tinctoria loaded zinc oxide nanoparticles were found to act against both gram-positive and gram-negative bacteria.

Green synthesis of silver nanoparticles using medicinal Fern Blenchnum Orientale leaves and its application as an antimicrobial agent against food borne pathogens

Nanotechnology is the most active research area in modern materials science. Though there are numerous chemical and physical methods, green synthesis of nanomaterials is the most recent. In the present study, silver nanoparticles were synthesized by plant mediated green approach method using leaf extracts of medicinal fern Blechnum orientale Linn, provides necessary bioactive for reduction of silver ions to silver nanoparticles. Blechnum orientale was commonly known as ‘Centipede fern’, which is an important edible medicinal fern. Synthesized nanoparticles were elucidated using UV-visible spectrophotometer, Fourier transform infrared spectroscopy (FT-IR), surface emission microscopy analysis (SEM) and its antioxidant activity was evaluated by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay as well as antimicrobial properties were studied against common food-borne pathogens. The highest absorbance of the produced silver nano particles (AgNPs) was 433 nm and the conversion of Ag+ ions to AgNPs was validated using Fourier transform infrared spectroscopy. FTIR result revealed the existence of O–H stretching and N–H amide group peaks. The as-synthesized AgNPs exhibited effective antibacterial action against food borne pathogens E. coli, Salmonella typhi, Pseudomonas aeruginosa and Shigella dysenteriae.

Significance of bioconvection and mass transpiration for MHD micropolar Maxwell nanofluid flow over an extending sheet*

Motivated by several practical submissions, the current modeling addresses the theoretical and numerical aspects of Maxwell micropolar nanofluids with diluted homogeneous diffusion of nanoparticles and gyrotactic microorganisms. Nanoparticles are considered due to extraordinary thermal conductivity, which are very useful in modern technology, electronics, heat exchangers, and material sciences. Further, gyrotactic microorganisms are incorporated to avoid possible sedimentation. The similarity variables are used to transform the flow equations into corresponding non-dimensional ODEs, furthermore these ODEs are transmuted into linear form by adopting shooting technique. The graphical and numerical results are utilized by computational software Matlab with Runge–Kutta order 4 method. Numerical and graphical consequences of velocity, micro-rotation, temperature, concentration and motile density profiles are displayed. As uplifting values of magnetic parameter, a twisting behavior is observed on micro-rotational profile but velocity profile is diminishing. The motile density profile is decline when Lewis and Peclet numbers are boosted. Temperature distribution increased for larger values of Brownian motion, Rayleigh number, and thermophoresis parameters.

MODIFICATION OF CEMENT-CONCRETE MIXTURES WITH POLYMER ADDITIVES, STRUCTURED CARBON NANOTUBES

The use of complex modifiers for cement-concrete mixtures and concretes is becoming increasingly popular in modern materials science. The paper presents studies of the effect of a polymer additive structured with carbon nanomaterial on the physical and mechanical characteristics of cement-concrete mixtures. IR spectroscopy and thermogravimetry revealed that the use of carbon nanomaterial significantly changes the structure of cement-concrete mixtures. As a result of the fact that high-strength nanomaterial is the center of crystallization of cement stone formations, a denser reinforced microstructure is formed, which significantly increases the strength characteristics of cement-concrete mixtures. Inclusion in the composition of cement-concrete mixtures of polymer complex additives leads to higher and longer plasticization, which plays an important role in the production of monolithic products. It is established that in the presence of a complex modifier (polymer additive structured with carbon nanotubes) the crystal structure of calcium hydrosilicates is compacted, which causes high physical and mechanical characteristics of modified cement-concrete mixtures. It is experimentally shown that the additive acts as an accelerator of hardening and hardening of cement paste, as well as increases its strength characteristics. In general, for all cement-concrete mixtures in this study there is a water-reducing effect of the additive. Water consumption decreases by 5 wt. %, while the strength increases by 19%. Formulations of cement-concrete mixtures modified with polymer additives, structured carbon nanotubes, with high performance characteristics have been developed.

Multicomponent Aging Al-Li-Based Alloys of the Latest Generation: Structural and Phase Transformations, Treatments, Properties, and Future Prospects.

An overview of modern material science problems is presented for ultralightweight high-modulus commercial Al-Li-based alloys in historical retrospect. Numerous particular examples of the Soviet and Russian aviation whose various designs were made of these alloys confirm their successful innovative potential. The key regularities of multicomponent alloying are discussed for the master alloys and modern commercial Al-Li-based alloys of the latest generation; the features typical of their microstructures, phase composition, and properties formed during aging are analyzed. The main mechanisms of phase formation are generalized for standard thermal and thermomechanical treatments. Recent original achievements have been obtained in designing of unique structural and phase transformations in these commercial alloys by means of methods of severe plastic deformations followed by heat treatment and storage. Using the example of three Russian commercial alloys of last generation, the basic principles of creating and controlling an ultrafine-grained structure, the origin and growth of stable nanophases of various types and chemical composition that determine the physicomechanical properties of alloys are established.