Journal of Material Science and Technology Research
Journal of Material Science and Technology Research provides a platform for researchers, academicians and scientists to discuss, share and promote their research work in the field of Material Science and Technology. Our aim is to publish outstanding and latest research articles concerning fundamental and applied research of Material Science. The information can be made at hand in the form of research articles, review articles, case reports, short communications etc.
Fungal Foams from Teak Leaves: Effect of Cold Shock and Species Variation on Growth and Mechanical Strength
Fungal foams represent sustainable alternatives to synthetic materials, yet optimization of growth and mechanical properties remains challenging. This study evaluated the effects of cold shock treatments at 0 °C for different interval days (3, 5, 7 days) on Pleurotus species including P. djamor, P. florida, and P. sajor-caju cultivated on teak leaves. Mycelial growth rates, mechanical properties (hardness, springiness, resilience), and scanning electron microscopy (SEM) were systematically evaluated. Results demonstrated that 3-day cold shock treatment consistently maximized growth, with P. florida (W3) achieving 1.41 cm/day. Mechanical testing revealed superior performance in 3-day treated samples: P. florida (W3) recorded peak hardness at 7904 g.sec, while springiness and resilience value reached 0.681 and 0.399 respectively for P. sajor-caju (G3) surpassing controls samples. SEM confirmed denser, thicker and intertwined hyphal networks in cold-treated samples, correlating with mechanical properties. These findings establish 3-day cold shock as an effective, non-chemical strategy to enhance fungal foam quality from agricultural residues.
Copyright (c) 2025 Journal of Material Science and Technology Research
Formation Mechanism of Eutectic Microstructure for CaHfO3/HfO2
The mechanism of fine eutectic structure formation for CaHfO3/HfO2 was investigated. CaHfO3/HfO2 eutectic solidification film was prepared using a high-power laser with 1400W. The film preparation was conducted in a furnace at 1300oC. The scanning speed of laser was set to 500 to 2000 mm/s. The scanning speed of the laser was greatly varied to create a solidified film and the intermediate steps of micro-structure formation were observed. The micro-structure morphology immediately after solidification was a structure in which an intermediate phase was surrounded by an HfO2 phase. CaHfO3 phase deposited in dot-like form from the intermediate phase. It was confirmed that the dot-like deposit phase connected through atomic diffusion at high temperatures, ultimately forming a fine lamellar structure. It was confirmed that the fine eutectic microstructure of CaHfO₃/HfO₂ is not formed by competitive growth at the melting point during conventional eutectic solidification, but rather is ultimately formed through repeated phase separation after the solidification.
Development of Polymeric Matrix Composite to Replace Grey Cast Iron in Precision CNC Machinery Structures
The structure of CNC machines must withstand the machining loads and have adequate rigidity to ensure the dimensional accuracy of the product. Gray cast iron is the material normally used in the bases of these machines because it has a relatively low cost, is easy to manufacture, has high compressive strength, and has a high vibration damping capacity. The objective of this work was to develop a rock particle reinforced polymer matrix composite with mechanical properties suitable for the design of precision CNC machining machine structures. Different resin and rock types were analyzed and 3 limestone particulate reinforced composites with 13%, 16% and 23% by weight of epoxy matrix phase were developed, and determinate their mechanical properties through compression tests ABNT NBR 5739/2018 standard. With the obtained values, tests were performed in a finite element software to evaluate the use of the material in the structure of the aircraft aircraft wing CNC machine. The results showed that the best mechanical properties were observed in the composite samples containing 16% epoxy, which by FEM test showed an increase in structural stiffness and a 25% reduction in the maximum deformation resulting from the application of machining loads.
Waste- and Refuse-Derived Fuels: Circular Energy Solutions from Waste Streams
This review explores the potential of waste-derived fuels (WDF) and refuse-derived fuels (RDF) as sustainable alternatives to conventional fossil fuels, addressing both energy recovery and waste management challenges. WDF and RDF are generated from diverse feedstocks—such as municipal solid waste (MSW), industrial by-products, and biomass—via mechanical, thermochemical, and biochemical processing. These fuels can be utilized in cement kilns, power plants, and industrial furnaces, contributing to reduced fossil fuel consumption. The manuscript classifies WDF and RDF into solid, liquid, and gaseous forms, examining their energy characteristics and combustion properties in comparison to coal, diesel, and natural gas. A detailed analysis of calorific value, moisture and ash content, and emissions profiles is provided to assess their performance. The environmental benefits, including decreased landfill usage, methane mitigation, and lower greenhouse gas emissions, are emphasized through life cycle assessments (LCA). Economic aspects such as production costs, energy substitution potential, and global market adoption trends are also discussed. Technological pathways including shredding, drying, gasification, pyrolysis, and anaerobic digestion are analyzed for their efficiency, capital investment requirements, and environmental impacts. The review also highlights current challenges—such as feedstock heterogeneity, emissions control, and public perception—and outlines future prospects enabled by technological advancements, regulatory support, and integration into circular economy frameworks. This comprehensive evaluation positions WDF and RDF as viable contributors to a low-carbon energy future, offering pathways for sustainable waste valorization and renewable energy generation.
Magnetocaloric Effect in La0.7Sr0.3Mn0.95Ni0.05O3 Manganite Via Mean Field Theory
This study investigates the magnetocaloric effect of La0.7Sr0.3Mn0.95Ni0.05O3 manganite, with a primary focus on leveraging the mean-field theory as a powerful tool for analysis. By applying this theoretical framework, alongside the Law of Approach to Saturation (LAS), key parameters such as saturation magnetization (Mo), total angular momentum (J), gyromagnetic factor (g) , and exchange parameter (λ) were determined. The mean-field theory proved essential for simulating the isothermal magnetization M (H,T) and the magnetic entropy change -∆SM (T)curves, providing a comprehensive understanding of the material’s magnetocaloric behavior. Despite its simplifications, the mean-field approach serves as a crucial starting point for modeling complex magnetic systems and offers valuable insights into the material’s thermodynamic properties.
Exploring the Potential of Chicken Feather-Reinforced Thermoplastic Polyurethane Composites for Sustainable Materials
This study explores the viability of chicken feather-reinforced thermoplastic polyurethane (TPU) composites as environmentally sustainable materials. Chicken feathers, an abundant keratin-rich biowaste generated by the poultry industry, were processed into both powder and fiber forms and subsequently subjected to chemical modification using (3-aminopropyl) triethoxysilane to enhance interfacial compatibility with the TPU matrix. Four composite formulations were produced via melt compounding, incorporating TPU-to-feather weight ratios of 90:10 and 85:15 for each morphological variant. Standardized test specimens were fabricated and evaluated through tensile, compressive, hardness, and density analyses. Among the formulations, the composite containing 85% TPU and 15% feather fiber exhibited the most favorable mechanical properties. The improved interfacial adhesion was attributed to the dual functional role of the silane coupling agent, which facilitated both covalent and hydrogen bonding at the filler–matrix interface. The findings underscore the potential of chemically treated feather waste as an effective and economical reinforcement for polymeric materials, advancing the development of high-performance, sustainable composites.
Temperature Characteristics of Magnetoelectric Effect in a Monolithic Langatate-Metglas Heterostructure: The Effect of Annealing
Magnetoelectric (ME) effects in ferromagnetic-piezoelectric heterostructures manifest themselves as a change in the polarization of the structure in an external magnetic field or a change in magnetization in an electric field. The effects are used to create magnetic field sensors, tunable electronic devices, and n1 ew data processing elements. To ensure the thermal stability of these devices, it is important to understand the temperature dependence of the ME effect characteristics. In this paper, we investigated the direct resonant ME effect in a monolithic heterostructure consisting of a langatate single crystal with FeBSiC amorphous ferromagnet films deposited on its surface. It was shown that heating of the structure from 220 K to 340 K resulted in a decrease in the quality factor of the acoustic resonance followed by a decrease in the ME coefficient. Annealing the structure in the presence of magnetic field led to an enhancement in the ME coefficient, a decrease in the optimal bias field, and improvement in thermal stability of the ME effect.
Hardness and Indentation Size Effect in Cubic Boron Nitride Materials (BL and BH Groups)
This paper investigates the hardness and indentation size effect (ISE) in cubic boron nitride (cBN) materials, specifically focusing on two groups: BL (below 70 vol.% cBN) and BH (more than 70 vol.% cBN). The study examines the load dependence of hardness in both groups, determining the load at which hardness becomes constant. Fracture toughness, (by the length of the crack) around indentations, is also evaluated for load dependence. The materials were synthesized using different additive combinations (Al, TiC, TiN, Mo) and sintered under high pressure and temperature. Hardness was measured using a Vickers indenter, and the ISE was analyzed using Meyer's law and the proportional sample resistance (PSR) model. Fracture toughness was calculated using the Niihara equation. Results show a significant ISE in BL materials, while BH materials exhibit less “load-hardness” dependence.
Proportional Sample Resistance (PSR) model
High Pressure High Temperature (HPHT) sintering
Fabrication of Free-Standing Porous BaTiO3 Thick Films by Indirect Selective Laser Sintering
The fabrication of free-standing porous thick films of ferroelectric BaTiO3, using a laser-assisted technique, is presented as a novel alternative to conventional methods. This approach adapts Indirect Selective Laser Sintering (ISLS) to create green films in a single laser pass, avoiding the complexities of traditional processes. Using commercial BaTiO3 powder and polyamide 12 as raw materials, laser processing parameters such as scanning laser speed and power were optimized to produce green BaTiO3 thick films with different thicknesses. After laser processing, the films were conventionally sintered and characterized for phase composition, microstructure, porosity, and electrical properties. X-ray diffraction and Raman spectroscopy confirmed the tetragonal BaTiO3 phase, while mercury intrusion porosimetry revealed a bimodal pore distribution. Impedance spectroscopy demonstrated a positive temperature coefficient of resistivity (PTCR) effect, with a peak resistivity near the Curie temperature. The PTCR behavior is hypothesized to arise from better oxygen adsorption due to the porosity and oxygen vacancies generated during sintering by carbon residues from polyamide degradation. The results demonstrate that ISLS is a versatile technique for producing high-quality, free-standing porous ceramic thick films with potential for a wide range of applications.
Reflections on the Potential of Applying Artificial Intelligence (AI) and Machine Learning (ML) for Screening Topical Hemostatic Agents Based on Inorganic Solids for Hemorrhage Control
Despite significant advances in medical interventions, fatal traumatic hemorrhage remains a leading cause of death worldwide. This persistent challenge has driven extensive research and development efforts aimed at creating more effective hemostatic agents to control bleeding. While most existing hemostatic agents are organic in nature, recent studies have highlighted the promising potential of mineral and synthetic inorganic materials for hemorrhage control. These materials demonstrate remarkable properties, such as rapid water adsorption from blood via their porous structures, which leads to the local concentration of proteins and cellular elements crucial for clot formation. Additionally, their negatively charged surfaces create a favorable environment for the activation of the intrinsic coagulation cascade. Although a variety of minerals and synthetic inorganic materials are currently employed as topical hemostatic agents, a vast array of emerging classes of inorganic materials remains underexplored. Many of these materials possess untapped hemostatic potential, but their properties and mechanisms for controlling bleeding are poorly understood. Moreover, synthesizing these materials with the precise characteristics required for effective hemostasis presents significant challenges. Recent advances in artificial intelligence (AI) offer a promising avenue to address these hurdles. By leveraging the growing availability of large datasets and sophisticated algorithms, AI can identify complex relationships within multidimensional systems, such as the synthesis of advanced inorganic materials. This capability is particularly critical for materials lacking well-characterized mechanisms or those with implications for hemostasis disorders, such as severe bleeding or thrombosis. AI-driven approaches could enable the design of innovative topical hemostatic agents capable of rapidly diagnosing and efficiently intervening in life-threatening situations, revolutionizing the field of hemorrhage control.
Seepage Analysis Beneath Gravity Concrete Dam Using Flow Net Method and PLAXIS 2D
Dam is a hydraulic structure that built across a river that construct especially for water supply, flood control, energy production, irrigation, recreation, and other. Many problems can occur on the dam construction such as seepage problem, which is seepage need to be controlled in purpose to meet the community’s requirement. In this study, the design and seepage analysis of the construction of a dam built on a river with spanning 400 meters which has a water height of up to 12 meters were carried out. The selection of the solution was obtained based on a numerical method using PLAXIS 2D and analytical analysis with the flow net method of seepage discharge Based on the analysis results, the best solution is obtained by making a dam design that suits the needs where the dam is made with a width of 20 m and a height of 20 m and with the addition of a cut-off structure at the foot of the dam on the left and right sides to a depth of 18 m so that the seepage discharge that occurs in less than 500 m3/day which is meet the community’s requirement. This result indicate that a cutoff wall beneath the dam can reduce and control the seepage on a hydraulic structure, but to design the dam with cutoff wall a couple of analysis need to do to predict the seepage which is with the analysis the seepage problem can be handled.
Bacterial Cellulose: A Multifunctional Platform for Biomedical Applications
Bacterial cellulose (BC), a biopolymer synthesized by various bacterial species, has emerged as a promising material for biomedical applications due to its unique properties, including high purity, biocompatibility, mechanical strength, and structural similarity to the extracellular matrix. This review explores the advancements in BC research over the last decade, focusing on its applications in tissue engineering, wound healing, and drug delivery systems. While BC offers numerous benefits, challenges such as large-scale production, structural modification, however regulatory approval hinder its broader clinical use. Recent studies have introduced innovative solutions, such as using agro-industrial waste to lower production costs and combining BC with other materials to enhance its bioactivity. As research progresses, BC has the potential to revolutionize the field of biomedicine, offering sustainable, versatile, and effective solutions for a wide range of medical applications.
Detecting Magneto-Optical Interactions in Nanostructures
Effects due to magneto-optical interactions are responsible for most of the phenomena discovered in optoelectronics and spintronics. Magneto-optical interactions can generate elementary excitations of the order of light-magnetic matter, which can flow under certain conditions. Here, we observe the intensities of magneto-optical interactions in hexagonal arrays of magnetic nanowires using experimental measurements and simulations. Nanowires of three materials (cobalt-Co, iron-Fe, and nickel-Ni) were electrodeposited on alumina membranes by the AC electrodeposition method. Our results reveal that the magneto-optical behavior can produce, under certain conditions, a kind of avalanche of magneto-optical interactions, which is dynamic. Such an observation shows the possibility of generating a magneto-optical current (spin-opto current).
Circular Economy: A Network Analysis of the Solid Waste Collection in the City of Rome (Italy)
Solid waste management represents a complex issue involving political, socioeconomic, institutional, urbanistic and environmental aspects. Separate collection of waste in the Municipality of Rome is a matter of particular interest due to the size of the city (with an urban area of 1,287 km²) and the considerable amount of waste produced (approximately 1,690,000 tons/year). In this context, this paper proposes an in-depth analysis with the aim of optimizing the delivery of waste to collection centres. The optimization focuses on several key elements, including the strategic distribution of collection centres within the city to make them easily accessible, particularly in densely populated areas or where waste production is higher. Based on the data provided by the Municipality of Rome, the waste materials that should be advantageously recycled as part of the Life Cycle Assessment (LCA) have also been identified. This comprehensive approach can improve the city’s waste management system, promoting the efficient use of resources and reducing environmental impact for greater urban sustainability.
Organic and Inorganic Modified Montmorillonite as a Scavenger of Formaldehyde in Modified Urea-Formaldehyde Composites
This research used montmorillonite (K10) modified with Hexadecyltrimethylammonium bromide (HDTMABr), and sulfuric acid (H2SO4). The samples are marked with MMT, OMMT for organic-modified montmorillonite, and AMMT for inorganic-modified montmorillonite. UF resin with a molar ratio FA/U = 0.8 was synthesized in situ with modified and unmodified MMT. X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), non-isothermal thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) were used to characterize the MMT samples. The degree of activation was determined based on the measurement of specific surface area, which was determined by the Sears method. The sulfite method was used to determine free and released formaldehyde from synthesized urea-formaldehyde/montmorillonite (UF/MMT) composites. SEM analysis showed changes in the OMMT morphology and the formation of a hollow network, affecting the clay's absorption capacity. Measurement of the specific surface area shows that higher values were obtained for AMMT (183 m2/g) compared to OMMT (13.5 m2/g). Despite that, the free and released formaldehyde amount was 0.06% and 4.6% for UF/AMMT and 0.1% and 1.0% for UF/OMMT. The larger interlayer spacing and hydrophobic nature of OMMT make it an effective barrier within the UF resin matrix.
Material Selection and Design for Assembly Applied in the Development of an Energy Generating Device
This study used the Design for Assembly (DFA) and material selection methods as tools to aid the development of a conceptual design of a functional device to transform alternate movement into rotational movement on the axis of a microgenerator. Also, material selection software was used to define the most suitable thermoplastic materials for some components of the projected device, focusing both on performance and low cost. There was a considerable reduction in the number of parts in the set from the basic device (prototype), which had 47 parts, to the conceptual design I, with 34 parts, and the conceptual design II, with 14 parts. The total mass of the set was also considerably reduced, from 160 grams for the basic device to 57.01 grams in the conceptual design I and, finally, 18.30 grams in the conceptual design II. Of thermoplastic materials analysed, considering a selection focused only on performance the most promising candidate, with an ideal set of properties is PEEK. But for a selection that considers the price, that is one of the key variables in the materials selection for most products, PEEK shows is prohibitively price.
Vibrocasting of Silicon Carbide Based Concrete Materials
In order to reduce the water demand of silicon carbide vibratory casting masses with high-alumina cement additives, the impact of various deflocculant of different natures to silicon carbide vibratory casting masses was investigated. The deflocculants used included polycarboxylate ether-based, sodium polyacrylate, high-molecular-weight poly-N-vinylpyrrolidone, and sodium salts of polymethylene-β-naphthalenesulfoxylic acid. Multifractional compositions of silicon carbide (2-3 mm, 1-2 mm, 0,5-1 mm, 0,2-0,5 mm, 0,063-0,12 mm fractions) with high-alumina cement and silicon additives, as well as with deflocculants, were studied. The firing of the materials was conducted in an oxygen atmosphere at temperatures between 1000 and 1400˚С. The adverse effect was demonstrated for deflocculant based on sodium polyacrylate and high-molecular-weight poly-N-vinylpyrrolidone, as the usage of these additives increases the water demand of the mix. A smaller amount of water used for the mass production allows the processing of more dense materials with reduced open and closed porosity. Using deflocculants, the moisture content of the material is reduced to 6.5%.
Evaluation of Mechanical Properties and Hydrophilicity of Alkaline and Plasma Treated Abaca Fiber Epoxy Composite with Mineral Waste as Fillers
Abstract: Natural fiber composites (NFC) are increasingly recognized for their sustainability and versatility. Abaca fiber is one of the prominent natural fibers that are sourced from the leaf sheaths of the abaca plant. This study provides an overview of the comparison of the mechanical properties and water uptake behavior of surface-modified N2 plasma and alkali treated abaca fiber-reinforced epoxy composites with granite powder used as fillers. It mentions the use of varying filler content (0 wt.%, 10 wt.%, 20 wt.%, and 30 wt.%) in both the pre-treated composites and compares their properties. Plasma-treated granite filler samples showed superior tensile strength and flexural properties, despite a negative effect on impact properties. A lower water absorption is observed in plasma-treated composites with fillers compared to those without fillers. Overall, the potential of surface modification techniques with granite-based mineral fillers is apparent in improving the performance of N2 plasma treated NFCs, thus expanding their applications across different industries aiming for the good mechanical hygroscopic properties.
Formation Mechanism of Eutectic Microstructure for Ca(Zr,Hf)O3/(Zr,Hf)O2 by Rapid Solidification Process at High Temperature
Abstract: Ca(Zr1-x,Hfx)O3/(Zr1-xHfx)O2 (x=0, 1/3, 0.5) eutectic film was prepared by rapid solidification process using high power laser irradiation method. The coating process was performed in an electric furnace at 1300°C. Solidified film with fine lamellar structure were obtained. When the Zr site was substituted with Hf, the lamellar spacing increased with the amount of the substitution. Separate from the solidification film prepared by laser irradiation, rapidly solidifying sample with x=0.1 composition was prepared using optical floating zone apparatus. The melt of the sample was free-fallen onto a copper dish. No film-like rapidly solidified sample was obtained. Hf ion was homogeneously solid-soluble in both phases of CaZrO3 and phase ZrO2.
Enhancing Mechanical Properties of a Lightweight TiAlCrNbVZr Medium-Entropy Alloy: Fine-Tuning Alloy Composition and Thermomechanical Treatment
Abstract: The quest to reduce fuel consumption and environmental pollution in the transportation sector has heightened the demand for developing lightweight alloys with enhanced mechanical properties. Accordingly, this study focused on optimizing the mechanical properties of a lightweight Ti65(AlCrNbV)28Zr7 medium entropy alloy (MEA) by strategically adjusting its Al, Cr, Nb, and V elemental contents. Hardness testing indicated a strengthening ability hierarchy of Cr > Al > V > Nb. Furthermore, tensile tests revealed that although a high Cr content significantly enhances strength, it also reduces the ductility of an MEA. Drawing on mechanical insights gained from a previously studied Ti60Al10Cr10Nb10V10 MEA and the present findings, a novel Ti60Al10Cr4Nb10V9Zr7 (Ti60Zr7) MEA was developed. This new alloy retains a single body-centered cubic structure and demonstrated exceptional mechanical performance in tensile testing, with a yield strength of 1066 MPa and 22% ductility. The Ti60Zr7 MEA underwent a series of thermomechanical treatments, including 50% hot rolling, 80% cold rolling, and rapid annealing up to 800 °C at a rate of 25 °C/s. After thermal processing, the Ti60Zr7 MEA not only preserved its single body-centered cubic structure but also achieved a remarkable combination of yield strength (>1200 MPa) and ductility (measured as >15% elongation). These advancements underscore the alloy’s considerable potential for application in sports equipment and transportation vehicles.
Microwave Absorption Performance of One-dimensional Mixed Metal Oxide Nanocomposite
Abstract: Microwave-absorbing materials have received numerous attentions in terms of their key roles in the fields of stealth technology and controlling electromagnetic radiation pollution. In this paper, we aim to develop one-dimensional CoFe2O4-TiO2 mixed metal oxide nanocomposite via combination of sol-gel method and electrospinning technique. and investigate its microwave absorbing capability. The phase evolution from precursor fiber to final product and corresponding micromorphology are characterized, and microwave absorption performance for different CoFe2O4-TiO2 composite fibers are investigated with a vector network analyzer in 2-18 GHz. The prepared CoFe2O4-TiO2 mixed metal oxide composite fibers exhibit excellent microwave absorbing ability. The low reflection loss can reach -32.8 dB, and the maximum effective bandwidth is up to 6 GHz (12-18 GHz) at the thickness of 4 mm. The results further reveal that the lightweight mixed metal oxide composite fiber is promising for applications in electromagnetic attenuation and other related research fields.
The Numerical Simulation of Welding Residual Stress of Dissimilar Transparent Thermoplastics with MZA Powder Absorbent
Abstracts: There are residual stresses in the joint caused by swift temperature variation in the process of laser transmission welding with metal absorbent. However, the related forming process is hard to detect through experimental methods. Herein, a physical model is established to describe the evolution of stress during the welding of polyarylsulfone (PASF) and polycarbonate (PC). The evolution of heat stress and the forming of residual stress is analyzed through the method of heat-force sequential coupling. In this process, the condensate transition, metal powder deformation, and clamping forces are involved in the mathematical model of stress-strain. In this model, the stress history can be divided into n time intervals according to the principle of superimposed stresses. The results revealed a significant correlation between the thermal history and stress evolution. Furthermore, the maximum von-mises stress appeared at the time of 1.7 s, then there was a decreasing tendency and stabled at 9 s. The von-mises stress was considered as residual stress after that time and the related stress distribution was investigated. The findings of this study provide a comprehensive understanding of residual stress on the joint.
Evaluation of Thermal and Mechanical Properties of Epoxy Resin/Aluminum Nanoparticle Composites
Abstract: In this study, we explored the development of epoxy resin nanocomposites with 0.1, 0.3%, and 1.0% by weight of aluminum nanoparticles. These nanocomposites were evaluated for mechanical properties (tensile test and Izod strength test) and thermal properties (differential scanning calorimetry and thermogravimetric analyses), and their morphology was assessed using field emission gun scanning electron microscopy. Adding even small amounts of aluminum nanoparticles led to notable improvements in the mechanical and thermal resistance. Remarkably, composites with 1.0 wt% of aluminum nanoparticles presented a 25% increase in the elastic modulus, a 20 °C increase in the glass transition temperature, and a 30 °C increase in the degradation temperature. These findings hold significant promise for advancing the field of polymer-metal nanocomposites.
Ballistic Energy Absorption of Thermally Aged DGEBA/TETA System and Fique-Fabric Reinforced Epoxy Composite
Abstract: For many applications, such as vests or parts of vests, the fibers are used in fabric, mat, or mesh. Ballistic resistance properties are also improved by the development of special fabrics architectures. It is known that heat and oxygen are the main factors in the aging process of polymers. The mechanisms of aging by oxidation can be investigated by monitoring the mechanical properties of a material exposed to prolonged aging in an oven, which is called the accelerated aging process by thermal oxidation. In previous studies, the epoxy matrix composite reinforced with 40% by volume of fique fabric, already tested and with good ballistic performance, was developed and proposed for individual ballistic protection applications. However, the impact of different environmental conditions on the dynamic properties of the composite has not been studied. Therefore, the present study, for the first time, aimed to apply accelerated weathering through high temperature to the composite, as well as to the epoxy matrix, aiming to evaluate the influence of aging.
One-Step Sol-Gel Facile Synthesis and 3D Nanoscale Morphology Investigation of Bi0.5Na0.5TiO3-BaTiO3 Thin Films
Abstract: Bismuth sodium titanate, denoted as Bi0.5Na0.5TiO3-BaTiO3 (BNT-BT), possessing a perovskite-like structure, has emerged as a highly prospective material in recent years. It is considered a prime contender for replacing PZT-based compounds due to its exceptional piezoelectric and ferroelectric properties, coupled with the presence of loosely bound pairs of chemically active electrons. This study delves into the micromorphological properties of BNT-BT thin film electrodes, fabricated using sol-gel spin-coating and subsequent annealing processes. Employing Atomic Force Microscopy (AFM), comprehensive 2D and 3D topographical maps were acquired, enabling the extraction of pivotal parameters crucial for surface characterization. Notably, the investigation encompasses Minkowski Functionals, which encompass normalized Minkowski volume, boundary, and connectivity analyses. In conjunction, various roughness parameters, encompassing arithmetic mean height, maximum peak height, maximum valley depth, arithmetic mean depth, and the ten-point height parameter, were quantified across these analyses to facilitate a comprehensive comparison of surface morphologies among distinct samples. The morphological analysis outcome underscores the potential for elucidating material performance through microstructural shape and quantitative roughness evaluation of respective surfaces. This holds significant promise for applications such as predictive assessment of functional behavior, including industrial quality control during sample manufacturing processes.
Crystal Structure and Magnetic Properties of Bi1-yBa(Sr)Fe1-yTiyO3 Solid Solutions
Abstract: Usages of various chemical substitution schemes of the initial multiferroic BiFeO3 can significantly reduce known drawbacks specific for the functional oxides based of iron ions and thus foster a creation of novel magnetoelectric compounds perspective for various technological applications. In the present study the co-doped compounds of the system Bi1-y(Ba1- xSrx)yFe1-yTiyO3 (x = 0.0 – 1.0; y ≤ 0.4) synthesized using sol-gel technique were analyzed focusing on the crystal structure stability and the correlation between the structure and magnetic properties. The concentration driven evolution of the crystal structure as well as the unit cell parameters were investigated based on the X-ray diffraction data, the correlation between the crystal structure and the magnetic properties of the compounds has been studied by magnetometry techniques. The compounds Bi1-y(Ba1- xSrx)yFe1-yTiyO3 with x = 0; y = ≤ 0.2 are characterized by single-phase rhombohedral structure, and increase in the dopant concentration to y = 0.4 leads to the stabilization of the pseudocubic phase. An increase in the Sr content leads to the phase transition in the compounds to the single phase state with the cubic structure which is accompanied by an increase in the value of the remanent magnetization.
Crystal Engineering for Achievement of Functional Materials Through Facile Intercalation of Lamella Mineral Kaolinite
Abstract: Kaolinite, a layered clay mineral, has attracted widely attention due to its versatile advantages including low cost, environmentally friendly processing and easy modification. By comparison of the wide studies of the intercalation processes of kaolinite via the replacement of diverse intercalated agents, the multiple functional properties of intercalated kaolinites are ignored as well as such kind of study is very limited. In this review, we have summarized a series of intercalated compounds of kaolinites with organic molecules or organic salts by means of a simple intercalation strategy. Additionally, their multiple functional properties (such as dielectricity, ferroelectricity and ionic conductivity) will also be mentioned.
3D Printing of β-TCP/S53P4 Scaffolds: Physicochemical, Mechanical, and Biological in vitro Evaluation
Abstract: The focus of bone tissue engineering is on the new strategies for developing bioactive and resorbable scaffolds, which have become an alternative to the treatment of bone diseases and trauma. β-tricalcium phosphate (β-TCP) is considered resorbable and has excellent osteoconductivity. In an attempt to achieve good densification of the β-TCP scaffold and improve its biological properties, it arises the possibility of combining this material with S53P4 bioactive glass. Several techniques are used to produce bioceramic scaffolds, among them, direct ink writing (DIW) a type of additive manufacturing based on material extrusion, which allows the production of customized parts, with high complexity and good reproducibility. This work prepared β-TCP and β-TCP/S53P4 (β-TCP/10-S53P4 = 10% wt of S53P4 and β-TCP/20-S53P4 = 20% wt of S53P4) scaffolds by DIW. The ceramic inks showed pseudoplastic behavior and the 3D-printed scaffolds showed similar aspects to the digital model. Also, the β-TCP/S53P4 scaffolds (β-TCP/10-S53P4 = 1.6 ± 0.6 MPa and β-TCP/20-S53P4 = 2.1 ± 0.9 MPa) showed an increase in compressive strength when compared to β-TCP scaffolds (0.9 ± 0.1 MPa). All scaffolds showed apatite-mineralization ability in SBF after soaking for 7 and 14 days, being that the β-TCP/20-S53P4 scaffold showed a higher ability of apatite formation compared to the other scaffolds. Concerning the biological in vitro assays, all the scaffolds showed good cell viability. Thus, the β-TCP/S53P4 scaffolds showed adequate properties which become them, good candidates, to be used in bone tissue engineering.
Enhancing the Catalysis for Electrochemical Water Splitting using Tri-metallic Phosphide Surface
Abstract: Hydrogen has been considered as one of the sustainable energy carriers and displays great potential for the ever-increasing energy and environmental demands. Electrochemical water splitting has been recognized as a clean and effective method to product hydrogen in future. Transitionally, the catalysts for water splitting are noble metal base materials but suffer from high cost and low reserves. Thus, developing cost-effective electrocatalysts is significantly important for the hydrogen generation. Here, we report a tri-metallic phosphide of NiCoFe-P as an effective electrocatalyst for both HER and OER, which can be prepared by a facile gas-phase reaction. Compared with monometallic or bimetallic phosphides, the tri-metallic NiCoFe-P exhibits outstanding activity. Specially, it obtains an OER current density of 10 mA cm-2 at an overpotential of 248 mV. Additionally, the NiCoFe-P catalyst shows remarkable stabilities even at a large current density of 50 mA cm-2. Moreover, a practical electrode of carbon paper supported NiCoFe-P only requires an overpotential of 267 mV to obtain an HER current density of 10 mA cm-2, and overpotentials of 235 mV and 296 mV for the OER current densities of 50 mA cm-2 and 100 mA cm-2, respectively. After a severe durability test of 5000 cycles of linear scan voltammetry, the carbon paper supported catalyst show no degradation. The remarkable catalytic performance should be due to the unique nanostructure and the synergism effect among the hetero-atoms.
Optimization with a Genetic Algorithm for Multilayer Electromagnetic Wave Absorption Cement Mortar Filled with Expended Perlite
Abstract: Due to the complexity of the design of multilayer electromagnetic (EM) wave absorbing materials, it is difficult to establish the relationship between material parameters (type and filling ratios) and EM properties using traditional trial and error methods. Based on the measured EM parameters within a few materials and Boltzmann mixing theory, a database of EM parameters was thereafter built up. In this study, the genetic algorithm (GA) was used to design the multilayer wave-absorbing cement mortar. In order to verify this method, a multilayer mortar was fabricated and measured. The simulated and measured results are well consistent, which convincingly verifies computer-aided design. In addition, the optimized result expresses that the first layer as a matching layer guides EM waves into the interior of the material, while the other layers as absorption layers attenuate EM waves. The multilayer material may not meet the impedance gradient principle but still exhibits better EM wave absorption performance. The reflection loss (RL) of all optimized three layer sample is below –6.89 dB in the full frequency band and the minimum RL is –26.21 dB. This composite absorbing material and the GA method provide more design ideas for the design of future cement-based wave-absorbing materials and save a lot of time and material cost.