Search

Abstract The work evaluated the usage of various filler materials, namely aluminium oxide (Al2O3), magnesium (Mg), and glass powder, in the bidirectional glass fibre reinforced polymer (GFRP) composites. The required samples were fabricated using the hand lay-up technique by varying the filler material proportions from 0%wt. to 7.5%wt., including individual and hybrid mixture combinations. The prepared samples were evaluated for their microhardness, tensile strength, deflection characteristics, and drop-weight impact resistance. It was observed that the optimal addition of individual filler material improved the microhardness and tensile strength more than that of neat composites. In contrast, hybrid compositions at higher proportions exhibited brittleness and lower enactment due to their poor interfacial bonding and particle agglomerations. The deflection characteristics and drop-weight impact tests also showed enhanced stiffness and impact resistance with the addition of hybrid mixtures of filler materials to the composites. The study supports the potential use of adding filler materials to the composites for lightweight structural applications.

One of the challenges facing our current and future generations is the effective management of energy and its acquisition through more sustainable means. One solution is using materials capable of generating energy from temperature differences. Construction materials could be the answer, as they are already integrated into structures and have good thermoelectric properties. Geopolymers, emerge as a promising candidate due to their enhanced sustainability compared to alternative materials. Our research explored the use of geopolymers for electricity generation from heat. To minimize the usage of kaolin, we incorporated 50 % of two mining residues obtained from old mines located in Portugal. This approach optimizes the utilization of mineral resources and mitigates the environmental impact. Various methods were used to characterize this material, such as X-ray diffraction, simple compressive strength tests and evaluation of thermoelectric properties, such as the Seebeck coefficient and figure of merit. The geopolymers tested exhibit semiconductor characteristics, demonstrating poor heat conduction due to their low thermal conductivity. Regarding thermoelectric properties, these materials display N-type behavior, with a Seebeck Coefficient between −643 μV/°C and −2760 μV/°C. These findings underscore the advantages of utilizing this sustainable material for the widespread implementation of energy management in buildings on a large scale. [ABSTRACT FROM AUTHOR]

The present article investigates the possibility of Extruded Polystyrene (XPS) waste to be used as a lightweight aggregate in cement-based materials for structural applications. The developed material offers a promising solution for rehabilitation and energy efficiency upgrades of existing civil infrastructures, providing thermal insulation without adding excessive weight to reinforced concrete structures. Through a comprehensive experimental approach, this contribution evaluates the mechanical and thermal performance of cement-based composites with varying XPS content (up to 100 %) as sand replacement. Results demonstrate a balance between enhanced thermal insulation and maintained mechanical robustness, with optimal XPS content ranges identified for specific application needs. The incorporation of XPS waste into construction materials supports sustainability by repurposing non-biodegradable materials, while meeting the dual requirements of structural performance and energy efficiency. This research supports the exploitation of XPS-modified cement-based materials in structural rehabilitation of existing structures and innovative construction applications, promoting greener and more efficient building materials that could be utilized in ground structures, such as buildings.

Ni‐based alloys provide good brazing filler characteristics for the many applications of SiC ceramics. Nevertheless, the presence of graphite is unavoidable in the reaction between Ni and SiC, leading to a significant degradation of the mechanical properties of the joint. This study investigates the effect of Mo in Ni–30Si alloy on the brazing of SiC at 1300°C, to regulate interfacial reactions and reduce residual stresses by decreasing overall coefficient of thermal expansion (CTE) values throughout the brazing process. The addition of Mo up to 8 at.% efficiently suppresses graphite accumulation by converting it into Mo2C + Ni3Mo3C phases and lowering the CTE to 5.4 × 10−6/°C. When the Mo loading exceeds 12 at.%, the interactions between the filler and SiC are reduced as a result of the non‐homogeneous dispersion of Mo. The experimental findings indicate that the joint without graphite has a lap shear strength of 107 MPa, which is nearly three times greater than the joint with graphite. Thermodynamic analyses are performed to provide a comprehensive understanding of the underlying mechanisms responsible for the formation of distinct phases in brazed joints. [ABSTRACT FROM AUTHOR]

Natural fiber-based polymer composite has great potential and is in high demand due to its high specific strength, low carcinogenic nature and economic market value. Tamarindus Fruit Fiber (TFF) has low density, high tensile strength and is easily available. It is one of the industrial waste materials. Polylactic acid (PLA) possesses an entangled coherence with fiber, since it is more compatible. A sample was prepared by integrating TFF as fiber and PLA as the binding agent. The fiber variations in all samples were 10 to 50 wt.% step by 10 wt.%. A pure PLA sample was also fabricated for the purpose of comparison. Mechanical properties such as tensile strength, flexural strength, impact and hardness have been evaluated. It was revealed that TFF reinforcement increased the mechanical properties of the samples. The highest mechanical properties were observed in Sample S5, which had 40 wt.% TFF and 60 wt.% PLA. Fracture failure was found using fractographic analysis. In conclusion, this study demonstrates the potential of utilizing TFF as an agricultural waste product for enhancing the mechanical properties of biodegradable polymer composites. These sustainable compositions of materials have been used for many applications in various industries, including packaging, automotive, and construction, while also providing an environmentally friendly solution for agricultural waste products. [ABSTRACT FROM AUTHOR]

This study uses high magnesium nickel slag (HMNS) directly as a raw material, to prepare high-temperature-resistant HMNS silico-aluminophosphate geopolymer (HMNSGP) activated by different types of acid activators including Al(H2PO4)3, H3PO4 and KH2PO4. By using characterization techniques such as XRD, FTIR, SEM-EDS, and MIP, the micro-properties, pore structure, and reaction mechanism of HMNSGP were investigated. The high temperature resistance of HMNSGP was evaluated by comparing compressive experiments before and after high temperature and TG-DSC. The results showed that the best samples were prepared using aluminium dihydrogen phosphate (ADP) at a P/Al molar ratio of 0.6. At room temperature, the main phases geopolymerized of the sample are crystalline products (Newberyite) and amorphous hydrated products (-Si-O-P-O-Si-, -Al-O-P-O-, -Si-O-Al-O-Si- and -P-O-Mg-). At 1200 °C, HMNSGP can still maintain its integrity, and its compressive strength can be increased to 48.4 MPa. The HMNSGP prepared using H3PO4 has the same hydration products as the optimal samples, but the lower amount of gel phase causes spallation at high temperatures. Besides primary phases geopolymerized with ADP as activator, the KH2PO4 sample includes crystalline products (K-struvite). However, this phase decomposes at 207 °C, affecting its high-temperature resistance while a significant volume shrinkage occurs at 1200 °C. In summary, using ADP with a P/Al molar ratio of 0.6 can directly prepare HMNS into an environmentally friendly refractory geopolymer material, the compressive strength shows stable growth after being exposed to 1200 °C. This results suggested that HMNSGP prepared with ADP can be used for structural applications, laying the foundation for future replacement of refractory cement.

Magnesium and its alloys have such advantages with lightweight, high specific strength, good damping, high castability and machinability, which make them an attractive choice for applications where weight reduction is important, such as in the aerospace and automotive industries. However, their practical applications are still limited because of their poor corrosion resistance, low high temperature strength and ambient formability. Based on such their property shortcomings, recently degradable magnesium alloys were developed for broadening their potential applications. Considering the degradable Mg alloys for medical applications were well reviewed, the present review put an emphasis on such degradable magnesium alloys for structural and functional applications, especially the applications in the environmental and energy fields. Their applications as fracture ball in fossil energy, sacrificial anode, washing ball, and as battery anodes, transient electronics, were summarized. The roles of alloying elements in magnesium and the design concept of such degradable magnesium alloys were discussed. The existing challenges for extending their future applications are explored.

As the lightest structural metal and one of the most abundant metallic elements on earth, magnesium (Mg) has been used as an “industrial metal” for lightweighting in the transportation and electronics industries, in addition to other traditional applications in aluminum alloying, steel desulfurization and protective anodes. In recent years, research has shown significant potential for Mg to become a “technology metal” in a variety of new applications from energy storage/battery to biomedical products. However, global Mg production has shown steady but moderate growth in the last three decades. Mg applications as an industry metal are still limited due to some sustainability concerns of primary Mg production, as well as a number of technical issues related to the structural and corrosion performance of commercial Mg alloys. New Mg applications as an industrial or technology metal face tremendous technical challenges, which have been reflected in the intensified global research efforts in the last twenty years. This paper will review some past and present applications, and discuss future opportunities and challenges for Mg research and applications for the global Mg community.

This study investigated the effects of using egg and snail shells, along with sugarcane bagasse, on various properties of hybrid reinforced epoxy composites for structural applications. The particulate shells and sugarcane bagasse serve as reinforcements while the matrix consists of epoxy resin and hardener. The composites were produced using the hand lay-up technique, and the mechanical, wear and physical properties of the prepared samples were evaluated. The fractured surfaces of the samples were examined using a scanning electron microscope. The results revealed that the source of the shell had an impact on the properties of the composites as eggshell-sugarcane bagasse particulate reinforced epoxy composites exhibited improved strengths, while snail shell-sugarcane bagasse particulate reinforced epoxy composites showed improved moduli. Optimal values were obtained for flexural and tensile strengths at 15 and 18 wt%, respectively, while flexural and tensile moduli were optimal at 12 and 15 wt%, respectively. Eggshell-sugarcane bagasse particulate reinforced epoxy composites demonstrated an optimal impact strength value of 21.81 J/m2, while snail shell-sugarcane bagasse particulate reinforced epoxy composites showed optimal results in all other properties mostly at 20 wt%. Conclusively, the use of snail shell-sugarcane bagasse particles was found to be more effective than eggshell-sugarcane bagasse particles for enhancing the properties of epoxy-based composites for structural applications while particulate reinforcement content within the range of 12–20 wt% are responsible for optimum performances. [ABSTRACT FROM AUTHOR]

Owing to the fast‐emerging nature and rapid advancements in the construction industry, huge volumes of marble dust (MD) are generated as reject during slab cutting in marble processing, causing significant environmental hazards. Nowadays, quartz composite slabs have increasingly been preferred in building works due to their excellent hygienic property and mechanical strength. Composite slab is produced using micronized quartz as filler, the grinding of which is an energy‐intensive process. Substitution of micronized quartz with MD at different percentages was investigated in natural form and after roasting. Natural MD offered appreciable physical properties closer to those of a quartz composite slab. Physical properties slightly retrograded by quartz supplementation in the raw form. Roasting the filler led to the formation of rounded Ca–silicate. Wollastonite was the first phase formed after sintering at the lowest MD percentage and shortest roasting times. Larnite became dominating phase first by increasing MD percentage and roasting time, and then calcio‐olivine formed. Physical characterization test results demonstrated that hardnesses of new phase and particle shape were the key parameters that improved slabs' mechanical properties of. Hard rounded larnite particles improved mechanical behavior of slabs having the synergic effect of quartz, whereas wollastonite did not show a significant effect. [ABSTRACT FROM AUTHOR]

• Summarize and discuss the roles of alloying elements in alloy design of degradable structural magnesium alloys. • Review the applications of such degradable structural magnesium alloys in various industries, including oil and gas industry, environment and energy industry. • Present and discuss the future challenges for the extensive applications of such degradable structural magnesium alloys. Magnesium and its alloys have such advantages with lightweight, high specific strength, good damping, high castability and machinability, which make them an attractive choice for applications where weight reduction is important, such as in the aerospace and automotive industries. However, their practical applications are still limited because of their poor corrosion resistance, low high temperature strength and ambient formability. Based on such their property shortcomings, recently degradable magnesium alloys were developed for broadening their potential applications. Considering the degradable Mg alloys for medical applications were well reviewed, the present review put an emphasis on such degradable magnesium alloys for structural and functional applications, especially the applications in the environmental and energy fields. Their applications as fracture ball in fossil energy, sacrificial anode, washing ball, and as battery anodes, transient electronics, were summarized. The roles of alloying elements in magnesium and the design concept of such degradable magnesium alloys were discussed. The existing challenges for extending their future applications are explored. [ABSTRACT FROM AUTHOR]

• Non/low-carbon production of primary Mg. • Increased end-of-life recycling of Mg components. • Corrosion-resistant and "stainless" Mg alloys. • Flame-resistant Mg alloy development. • Alloy development for high thermal and electric conductivity. • Mega-casting development. • Room temperature sheet applications. • Additive manufacturing. • Mg-ion battery development. • Hydrogen storage. As the lightest structural metal and one of the most abundant metallic elements on earth, magnesium (Mg) has been used as an "industrial metal" for lightweighting in the transportation and electronics industries, in addition to other traditional applications in aluminum alloying, steel desulfurization and protective anodes. In recent years, research has shown significant potential for Mg to become a "technology metal" in a variety of new applications from energy storage/battery to biomedical products. However, global Mg production has shown steady but moderate growth in the last three decades. Mg applications as an industry metal are still limited due to some sustainability concerns of primary Mg production, as well as a number of technical issues related to the structural and corrosion performance of commercial Mg alloys. New Mg applications as an industrial or technology metal face tremendous technical challenges, which have been reflected in the intensified global research efforts in the last twenty years. This paper will review some past and present applications, and discuss future opportunities and challenges for Mg research and applications for the global Mg community. [ABSTRACT FROM AUTHOR]

This study focuses on developing cost-efficient engineered cementitious composites (ECCs) with glass and polypropylene fibers, using local materials for sustainable construction in developing countries. The ECC exhibits unique properties such as strain hardening, enhancing structural resilience and crack mitigation. The composite utilizes 1–2% volume of 6mm fibers, with fly ash as a supplementary cementitious material and a superplasticizer. The PPGF-ECC surpasses PC in mechanical properties, making it suitable for various applications, including rigid pavements in developing countries. This research recommends 2% PPGF-ECC for various applications in developing countries, including rigid pavements, due to its superior performance. [ABSTRACT FROM AUTHOR]

Ultra-high-performance concrete commonly known as UHPC is rising curiosity among structural engineers all over. Though early research on this material dates back to a couple of decades, some initial knowledge about this material, its behavior, and its properties is largely limited to a few research circles in a handful of advanced countries. This paper introduces UHPC as a material, elaborates on its ingredients, and describes its properties. A detailed review of available research literature about UHPC is made. The contributions made by several researchers have been discussed in detail. Following this, the structural behavior and strength of the material are reviewed comprehensively. Comparisons are made between conventional concrete and UHPC with respect to their properties, stress-strain relation, cracking behavior, compressive, tensile, and shear strengths. A detailed evaluation is made of the enhanced properties of the material with respect to its durability and long-term performance. The resistance of this material to moisture permeability, chloride ingress, and chemical attacks is understood. The impact resistance and energy absorption characteristics of the material are compared with conventional concrete. The study documented the structural applications of UHPC as well as the potential applications in the field of civil engineering. Finally, the authors enlisted the impacts of this new material (UHPC) on the future direction of structural engineering and the innovative solutions it can provide to structural engineering problems. [ABSTRACT FROM AUTHOR]

Abaca is a strong competitor among natural fibres for use as the reinforcement of polymer composites. Due to its high durability, considerable fibre length, flexibility and mechanical strength, abaca shows good potential as a renewable source of fibres for application in technological and industrial fields. Discussing the influence of various treatment strategies, such as alkali and silane, for the preparation of abaca-based composites results in the improvement of their properties over that of bare polymer materials and that of other synthetic fibres. The enhanced characteristics of abaca fibre reinforced composites are widely explored for a variety of applications in automotive and other industries. These include for example roping and woven fabrics, currency notes, cigarette filter papers, vacuum bags, tea bags, cellulose pulp for paper and packaging, and materials for automotive components, etc. In particular, the effective use of abaca fibre reinforced polymer composite in manufacturing external parts of cars, using therefore also thermoplastic matrices, has become popular. The gaps in research from the literature that show the scarcity of studies on topics such as simulation and designing of mechanical characteristics of abaca fibre composites constructed on polymer matrices, such as epoxy, polylactide, high density polyethylene, phenol formaldehyde and polyester are also highlighted. The results indicate that abaca is particularly flexible to be used in different sectors, in combination with various matrices, and in hybrid composites with various fibres. Further work would necessarily involve the larger consideration of abaca textiles with different areal weights in the production of composites, and a widespread introduction of abaca in datasets for the automated selection of natural fibres for composites reinforcement. [ABSTRACT FROM AUTHOR]

Present review is focused on recent experimental and computational advances of the liquid‐phase deuterium nuclear magnetic resonance (NMR). Nowadays, isotropic liquid‐phase 2H NMR became one of the most important instruments for the identification and certification of organic compounds of biological interest together with natural products and biosynthetic molecules. Of special interest are the 2H NMR biochemical and microbiological applications. This review consists of three main parts. The first part deals with the practical applications of 2H NMR to organic compounds of biological interest. The second part is connected with natural products and biosynthetic molecules, while the third part exemplifies and outlines 2H NMR advances in biochemistry and microbiology. [ABSTRACT FROM AUTHOR]

The design of porcelain stoneware tile composition is a very complex and time-consuming task, in the industry. After the long way to accomplish the product, processing, and cost requirements, the microstructure is seldom analyzed. If it is checked, it is not adjusted. The raw materials' chemical composition is one of the most helpful information to design. However, it has certain limitations because the mineralogy information is hidden. The paper approach formulates and optimizes porcelain stoneware compositions regarding raw materials' microstructure and mineralogy. Meta-analysis was applied to build models for mullite formation, firing temperature, and pyroplastic deformation. Kaolinite, illite/muscovite, talc, quartz, and feldspar were used as regressors. The robust microstructure is formed with interconnected mullite crystals. This feature could be numerically correlated to the mullite content ranging from 14% to 17%. Optimization was performed with mullite constrained from 13.5% to 17.5%, firing temperature <1230 °C and pyroplastic deformation <4.8x10−5 cm−1. It was possible to find feasible compositions' intervals. For instance, kaolinite needs to be between 23% and 37%. The comparison with 34 industrial compositions found that 90% of them have kaolinite content below the robust interval. This means it has opportunities to improve product and process performance in terms of stability, quality, cost, productivity, waste material incorporation, and sustainability. [ABSTRACT FROM AUTHOR]

Thermal insulating materials are such materials that do not allow the movement of heat through themselves. The material must have lower thermal conductivity to work efficiently as an insulator. Conventionally glass wool, calcium silicates, concrete, and processed wood particle boards are well‐known thermal insulators used for construction purposes. The thermal conductivity of glass wool is near about ~0.02–0.04 W/mK, and calcium silicates are also around ~0.08 W/mK. In contrast to these fabrication techniques, 3D printing or additive manufacturing has emerged as the most in‐demand fabrication method. The scope of versatility in shapes, design, dimension, and finish that 3D printing yields are enormous, and their performance is significantly comparable and, in some cases, better than conventionally prepared materials. 3D printing includes various methods such as FDM, SLA, SLS, DIW, and so on. Recent literature has shown the fabrication of thermally insulating material using raw materials like silk fiber, fly ash, cement, polymer composite, metal oxides, and so on, through additive manufacturing. These materials have very low thermal conductivity, as low as 0.03–0.08 W/mK for SLA and DIW printed silivoxel, cellulose nanocrystals composites having 0.08–0.09 W/mK and 0.04 for PU and cork composites. The low thermal conductivity values indicate their possible and efficient application as thermal insulators. [ABSTRACT FROM AUTHOR]

Natural fiber-based polymer composite has great potential and is in high demand due to its high specific strength, low carcinogenic nature and economic market value. Tamarindus Fruit Fiber (TFF) has low density, high tensile strength and is easily available. It is one of the industrial waste materials. Polylactic acid (PLA) possesses an entangled coherence with fiber, since it is more compatible. A sample was prepared by integrating TFF as fiber and PLA as the binding agent. The fiber variations in all samples were 10 to 50 wt.% step by 10 wt.%. A pure PLA sample was also fabricated for the purpose of comparison. Mechanical properties such as tensile strength, flexural strength, impact and hardness have been evaluated. It was revealed that TFF reinforcement increased the mechanical properties of the samples. The highest mechanical properties were observed in Sample S5, which had 40 wt.% TFF and 60 wt.% PLA. Fracture failure was found using fractographic analysis. In conclusion, this study demonstrates the potential of utilizing TFF as an agricultural waste product for enhancing the mechanical properties of biodegradable polymer composites. These sustainable compositions of materials have been used for many applications in various industries, including packaging, automotive, and construction, while also providing an environmentally friendly solution for agricultural waste products.

Two new high-pressure modifications of sodium yttrium germanate NaYGeO 4 are described. A reversible pressure-induced phase transition of olivine-type NaYGeO 4 to new phases has been studied in the pressure range of 4–10 GPa at temperatures from 400 to 1000°C. It was shown that NaYGeO 4 olivine is stable at 400–600°C up to 10 GPa. A high-pressure polymorph of NaYGeO 4 with NaNdSiO 4 crystal structure is formed at 800°C starting from 6 GPa. Along with this polymorph, another new high-pressure modification of NaYGeO 4 with NaSmSiO 4 crystal structure was found in small amount. In addition, a yet undescribed polymorph of Y 2 Ge 2 O 7 with pyrochlore-type structure was isolated at 8 GPa and 800°C. The crystal structures of the new phases were determined by X-ray powder diffraction. The results of DFT calculations confirmed the experimental crystallography and gave a preliminary insight into the relative thermodynamic stability and electronic properties for all three new compounds. [ABSTRACT FROM AUTHOR]

In the present study, andesite basalt originated from the deposit site “Donje Jarinje”, Serbia, was examined as a potential raw material for high-density ceramics production. The production of high-density ceramics included dry milling, homogenization, cold isostatic pressing and sintering in the air. To determine the optimal processing parameters the sintering was conducted at 1040, 1050, 1060, 1070 and 1080°C, and afterwards the sintering duration was varied from 30 to 240min at the optimal sintering temperature of 1060°C. Characterization of the starting and sintered materials included the estimation of particle size distribution, density, hardness and fracture toughness complemented with X-ray diffraction, optical light microscopy, scanning electron microscopy and energy dispersive spectroscopy analysis. Phase transformations did not occur during processing in the investigated temperature range from 1040 to 1080°C. The obtained research results showed that 99.5% of relative density and the highest hardness and fracture toughness values of 6.7GPa and 2.2MPa•m1/2, respectively, were achieved for the andesite basalt sintered at 1060°C for 60min in the air. The results of the present study confirmed that the sintered andesite basalt can be used as a high-density ceramic material for various industrial applications.

Designing a building material with excellent heat resistance is crucial for protection against catastrophic fires. Geopolymer materials have been investigated as they offer better heat resistance than traditional cement owing to their ceramic-like properties. Curing temperature and conditions are crucial factors that determine the properties of geopolymers, but their impacts on the heat resistance of geopolymers remain unclear. This study produced geopolymers from fly ash and ground granulated blast furnace slag by using sodium silicate and sodium hydroxide solutions as alkaline solutions. To examine the effect of curing conditions on the high-temperature performance of geopolymer, four different curing conditions, namely, heat curing (70 °C for 24 h), ambient curing (20 °C), water curing, and the combination of heat and water curing (70 °C for 24 h followed by water curing), were applied. At 28 d, the specimens were subjected to high temperatures (500 °C, 750 °C, and 950 °C), and their mechanical and microstructural evolutions were studied. The results revealed that the curing condition significantly affects the properties of the unexposed geopolymer; the effect on its high-temperature performance is insignificant. Furthermore, all the specimens could maintain adequate compressive strength after exposure to the maximum temperature of 950 °C, promising the use of geopolymer for structural applications. [ABSTRACT FROM AUTHOR]

In the present work, lithium aluminosilicate (LAS) reinforced with SiC nanoparticles (nSiC) is successfully prepared by slip-casting for the first time. The stability of aqueous suspension is investigated in terms of its rheological properties. The isoelectic point (IEP) of β-Eucryptite particulate system was found to be at pH 6.1. To obtain the best processing conditions, LAS-nSiC suspension with 55 wt% of solids and 0.06 wt% of Tetramethyl ammonium hydroxide (TMAH) as dispersant is recommended. The slurry is slip-casted in plaster of Paris molds and sintered at 1430ºC for different holding times in controlled atmosphere. Microstructure, mechanical and coefficient of thermal expansion (CTE) properties of the sintered samples have been evaluated. LAS-nSiC composite sintered at 1430ºC shows dense and free-cracked microstructure with a CTE close to zero. • LAS-nSiC samples with large and complex symmetry are obtained by slip-casting. • High density, good mechanical properties and CTE close to zero are reached. • Glassy phase allows controlling the grain growth and avoiding the microcracking. • The material is suitable for a wide range of technological applications. [ABSTRACT FROM AUTHOR]

This study focuses on developing cost-efficient engineered cementitious composites (ECCs) with glass and polypropylene fibers, using local materials for sustainable construction in developing countries. The ECC exhibits unique properties such as strain hardening, enhancing structural resilience and crack mitigation. The composite utilizes 1–2% volume of 6mm fibers, with fly ash as a supplementary cementitious material and a superplasticizer. The PPGF-ECC surpasses PC in mechanical properties, making it suitable for various applications, including rigid pavements in developing countries. This research recommends 2% PPGF-ECC for various applications in developing countries, including rigid pavements, due to its superior performance.

Sialons are the spotlight of current investigation as low-cost and outstanding alternatives to the currently used metal alloys in various applications. The excellent high-temperature properties, high mechanical properties, structural reliability, good sinterability, easy densification with its low-cost processing make them superior candidates in many applications such as automotive engines, high-performance bearings, wear components, and gas turbine blades. In addition, the existence of two interstitial crystallographic sites in their crystal structure gives the opportunity to accommodate some rare earth element activators such as Eu2+, Yb2+, Ce3+, and Pr3+. These types of sialon-based materials have recently found a new promising application as a luminescent material for white light-emitting diodes. The aim of this review is to survey and provide a comprehensive look at the most relevant and significant publications regarding the development of sialons and their processing into both structural and luminescent materials. Such information forms a database that could enable scholars and engineers to tailor a final product derived from sialons with specific characteristics for a certain application. This review article should be of concern to engineers and scientists interested in the development and utilization of sialons for structural and wLEDs applications.

Sustainability and environmental protection have given rise to the use of renewable and biobased materials in several application areas. Fibre reinforced composites are currently gaining a high market value in both structural and semi-structural applications. Making these materials environmentally friendly, renewable and lighter will protect the environment and increase resource use efficiency. Opposed to synthetic fibres such as carbon and glass, natural plant fibres are less expensive, lighter, degradable, easy to produce, non-toxic and environmentally friendly. However, natural plant fibres are inferior to their synthetic counterparts in both mechanical performance and tolerance to harsh environmental conditions. One method of compensating for these disadvantages is to combine natural and synthetic fibres in a single matrix forming a hybrid composite where the disadvantages of one are compensated by the other. In this way, sustainability and cost minimisation are achieved with acceptable mechanical and physical responses. However, successful implementation and advancement in the development of natural plant fibre reinforced polymer (FRP) hybrid composites require the development of workable conceptual design, suitable manufacturing techniques and understanding of the strengthening mechanisms. The main objectives of this review are to critically review the current state of knowledge in the development of natural FRP hybrid composites, outlining their properties and enhancing them while reducing environmental impact of the product through the hybridisation approach.

This work presents a new CFD model developed to investigate the SiC film growth over a fuel combustion nozzle in the commercial hot-wall CVD reactor. A detailed 3D model consisting of the compressive transport models and the reaction mechanism to account for the chemistry of the gas-phase and surface reactions are developed. The velocity, temperature, and concentration profiles inside the reactor are predicted numerically. The multispecies transport and its interplay with the gas and surface reactions are understood to operate the reactor effectively. The natural convection and hydrodynamics stability of the flow is investigated using various dimensionless groups (Re, Pr. Pe, and Gr/Re2). It has been observed that the buoyancy-driven flow is dominant at a large Reynolds number (Re) and Gr/Re2 ratio. This results in flow recirculation, which ultimately deteriorates the film uniformity. A sensitivity analysis is performed to identify how critical parameters affect the deposition process. Besides, the optimisation of the CVD reactor is also served by combining the support vector machine, a versatile supervised machine learning method, and the Nelder-Mead algorithm to improve the film quality. Our results demonstrate that the present methodology effectively obtains optimal process conditions, significantly enhancing the film performance. [ABSTRACT FROM AUTHOR]

The mechanical properties of plantation Eucalyptus Nitens timber are currently assessed by applying visual stress grading (VSG) designed for the sawn timber from the mature plantation and do not represent the actual characteristics of the resource. However, the well-known limitation of VSG application for this resource led to the discovery of other methods to grade the timber to its relevant structural grade. There is potential for hardwood plantations in Australia to supply wood to the timber industry and be used in structural applications. However, it is necessary to employ criteria to evaluate the structural properties of this resource before it could be satisfactorily used for structural purposes. This research aimed to assess the use of non-destructive technique (NDT) through acoustic wave velocity (AWV), machine stress grading (MSG), and multiple linear regression (MLR) model to predict the modulus of elasticity (MOE) as a grade-determining factor. The results showed that there was a strong correlation (R2 = 0.88) between the dynamic MOE (MOEdyn) and static MOE (MOEs) of the boards, proving the NDT as a reliable method for the MOE estimations of E. nitens timber. The results from the MLR model also showed that the density and AWV are effective parameters and their combination can be practical to estimate the MOE. There was a high correlation between the MOE obtained from MSG and MOE obtained from four-point bending, demonstrating that the MSG method through the flat-wise bending can be a suitable method for fast grading. The results also indicated that the measured MOE in the edgewise direction correlates with both the flatwise and longitudinal directions. The results also showed that the E. nitens timber resource has the potential to be used in structural applications with a wide range of MOE from 7 GPa to 21 GPa. [ABSTRACT FROM AUTHOR]

Developments of lignocellulosic natural fibers reinforced hybrid thermosetting composites (LNFRHTCs) are essential in the current scenario as far as the environmental safety is concerned. The hybrid composites develop from this type of materials are aiming to introduce new dimensions for sustainability. LNFRHTCs exhibit a wide range of high-end properties suitable for structural applications. Moreover, the improvement of hybrid composites by incorporation of natural fibers is economical and possesses several advantages including recyclability, cost-effectiveness, biodegradability, and their abundant availability. Presently, LNFRHTCs are one of the developing materials that have been found in current researches that are gaining attention for structural applications in various sectors such as automobiles, marines, defense military, aircraft, buildings, and constructions etc. In this review paper, we present several recently published studies associated with physical, mechanical, thermal, properties and processing techniques of natural fibers, their hybrids with thermosetting matrix materials. This paper will illustrate the importance of hybridization of natural/synthetic fiber and their hybrid composites as well ensuing to enhanced desired properties for high-end structural applications. [ABSTRACT FROM AUTHOR]

Sialons are the spotlight of current investigation as low-cost and outstanding alternatives to the currently used metal alloys in various applications. The excellent hightemperature properties, high mechanical properties, structural reliability, good sinterability, easy densification with its low-cost processing make them superior candidates in many applications such as automotive engines, high-performance bearings, wear components, and gas turbine blades. In addition, the existence of two interstitial crystallographic sites in their crystal structure gives the opportunity to accommodate some rare earth element activators such as Eu2+, Yb2+, Ce3+, and Pr3+. These types of sialonbased materials have recently found a new promising application as a luminescent material for white light-emitting diodes. The aim of this review is to survey and provide a comprehensive look at the most relevant and significant publications regarding the development of sialons and their processing into both structural and luminescent materials. Such information forms a database that could enable scholars and engineers to tailor a final product derived from sialons with specific characteristics for a certain application. This review article should be of concern to engineers and scientists interested in the development and utilization of sialons for structural and wLEDs applications. [ABSTRACT FROM AUTHOR]

In this paper, we present an efficient and effective method to predict the pressure dependence and temperature dependence of second-order elastic constants (SOECs) by introducing third-order elastic constants (TOECs) in the monocarbide ultrahigh temperature ceramics. The method is validated by comparing with experiments and previous calculations in four TMCs (TM = Nb, Ti, V, Zr). Using this method, we investigate the derivatives of SOECs against pressure and temperature as well as the anisotropic properties of polycrystalline modulus. In addition, we fit the SOECs with pressure and temperature under the framework of CALPHAD for practice usage. [ABSTRACT FROM AUTHOR]

The sinterability of 3Y-TZP/TiO 2 materials using micrometre-sized ZrO 2 and nanometre-sized TiO 2 (16 wt%) by one-step fast microwave sintering at low temperature (1200–1300 °C) was investigated. Firstly, in situ detailed analysis of the dielectric properties of the material with temperature was carried out in order to measure the capacity of the material to transform microwave energy into heat. Another related parameter associated to microwave sintering is the penetration depth of the microwave radiation into the material, which showed great homogeneity from 400 °C. Secondly, the effect of sintering conditions on microstructure, density, hardness and coefficient of thermal expansion was evaluated. The X-ray diffraction study and microstructural characterization demonstrate that it is possible to obtain fully dense pieces (>99%) by microwave sintering, a condition yielding to a coarse-grained (~1–2 μm), quite hard (~13.7 GPa) 3Y-TZP/TiO 2 material. However, the most important feature is the significant reduction of the thermal expansion coefficient (8·10−6 K−1) as compared to that of 3Y-TZP. In addition, the results from conventional sintering at 1400–1500 °C with 2 and 6 h of dwell time are examined and compared. The materials obtained at 1500 °C showed high density with grain size and hardness similar to those obtained by microwave but with a dramatic difference in the power consumption of the sintering cycle, since the materials obtained by microwave used a maximum absorbed power of 120 W and a heating cycle of only 40 min. [ABSTRACT FROM AUTHOR]