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Steel slag powder-cement composite mortar (SSP-cement mortar), a low-carbon building material with industrial solid waste can effectively utilize SSP. However, the low hydration activity of SSP has a significant adverse effect on its early-age behavior. In this study, the early-age compressive behavior and stress–strain relationship of a high-strength SSP-cement mortar at the first curing period of 7 days were comprehensively studied. The mix proportion parameters include the replacement ratio of SSP Rs, cement strength grade fce, mesh of SSP ν, and water-binder ratio W/B. The curing temperature was set at T = 20℃ and T = 80℃. The results indicate that: firstly, at T = 20℃ and T = 80℃, the optimal values for cube compressive strength fcu are 71.2 MPa and 112.4 MPa, respectively, axial compressive strength fc are 50.1 MPa and 85.4 MPa, respectively. Secondly, with the increase of Rs, the fc, elastic modulus Ec, and toughness U, showed decreasing trends, the peak strain εcp shows an increasing trend. The trends have weakened at T = 80 ℃. With the increase of fce and ν, all the indexes (fc, εcp, Ec, and U) show an upward trend. With the increase of W/B, all the indexes show a decreasing trend and are more pronounced at T = 20℃. Finally, an early compressive stress–strain relationship of SSP-cement mortar was established. Based on the given parameters and curing temperatures, a compressive strength prediction model is provided to guide engineering applications. [ABSTRACT FROM AUTHOR]

A high-strength Al-Mg-Si alloy was prepared using mechanical alloying (MA) combined with press-forming (PF) technology, achieving a strength of up to 715 MPa and a hardness of 173 HB. The microstructures were comparatively analyzed with conventional cast Al-Mg-Si alloys using XRD, TKD, and TEM. The XRD results showed that the full width at half maximum (FWHM) of the alloy prepared by MA+PF was significantly broadened and accompanied by a shift in the diffraction peak. TKD revealed that the grain size of the MA+PF processed alloy was significantly reduced to approximately 260 nm, indicating substantial refinement compared to the cast alloy. Additionally, using TEM, it was found that the newly developed MA+PF alloy exhibited a distinct morphology of Mg2Si precipitation phases and a high density of stacking faults (SFs), characteristics that differed from those in the cast alloy. The significant enhancement in strength can be attributed to the synergistic strengthening effects of grain refinement, second-phase precipitation, and stacking fault strengthening, as synthesized and analyzed. [ABSTRACT FROM AUTHOR]

With the depletion of fossil fuels, more and more green products are appearing in daily necessities. Bamboo is a common sustainable biomaterial with the characteristics of fast growth, easy bending, low cost, and easy processing, and it is widely used in furniture design. However, the poor aging resistance and UV resistance of natural bamboo materials limit their application in outdoor furniture. In order to improve the service life of outdoor bamboo furniture, this study prepared bamboo boards from bamboo powder and utilized them in the design of outdoor furniture. The research was conducted in two stages. In the first stage, functional modification was carried out on the surface of bamboo fibers (BF). Epoxy resin and UV absorber ZnO were introduced into the bamboo powder matrix, and a three-dimensional network structure of bamboo powder-based polymer material was formed by adjusting the material ratio and reaction conditions. With the increase of ZnO content, the absorption of moisture by the bamboo powder-based polymer materials decreased. The compressive strength of 1.5%ZnO-Board reached 36.8 MPa, exceeding the compressive strength of C30 concrete. In the second stage, 1.5% ZnO-Board was selected for solidification and demolding, and used as the seat surface for outdoor chairs. Through the car crushing experiment, the chair panel did not undergo significant deformation during the car crushing process. The anti-aging experiment showed that the structure and morphology of the panel would not be damaged by long-term UV irradiation. The panel did not show any weight changes in the anti-water-absorption experiment. By using low-contrast color combinations, the seats can be organically integrated into the environmental background, effectively enhancing the coordination and unity of the overall aesthetic harmony of the space. Compared with the commonly used plastic outdoor seats, the outdoor seats prepared in this study showed a 144% increase in carbon reduction effect. This study highlights the potential of modified bamboo powder for the design of outdoor furniture, which is of great significance to reducing outdoor plastic products and promoting sustainable life. [ABSTRACT FROM AUTHOR]

The mechanical properties of models are crucial in determining the industrial applications of additive manufacturing techniques. Material jetting (MJ) has been primarily limited to mold-making, prototyping, etc., owing to its low strength. Low viscosity and rapid curing, which are essential ink characteristics of MJ, lead to the low strength of MJ models. This study aimed to develop methods to increase the strength of MJ models by adding fillers to the ink. We optimized the shape and size of the filler, modified the surface properties, and optimized the methacrylate monomer formulation of the ink. To develop a colorization process suitable for filler-added inks, we investigated a method to apply transparent ink over small-colored ink droplets. We achieved a bending strength of 180 MPa for colorless models and 177 MPa for colored models, which is remarkable compared to the typical MJ product strength of 90 MPa or less. These findings clarify the design guidelines for high-strength MJ ink, making the direct manufacturing of production parts requiring both esthetic beauty and high strength in colors, such as artificial teeth, dentures, and eyeglass frames, more realistic. [ABSTRACT FROM AUTHOR]

SiC particles were added to the Mg97Zn1Y2 alloy to improve its mechanical properties and damping properties. The microstructure, mechanical properties, and strain amplitude dependence of high-damping and high-strength SiC/Mg97Zn1Y2 magnesium matrix composites were analyzed. The strain amplitude-dependent damping of SiC/Mg97Zn1Y2 composites and the effect of SiC on this property were discussed herein. In anelastic damping, the strain amplitude-dependent damping curves of the composites were mainly divided into two sections, dominated by the G-L model. When the strain amplitude reaches a certain value, the dislocation motion inside the matrix becomes complicated. Moreover, the damping of the material could not be explained using the G-L model, and a new damping model related to microplastic deformation was proposed. In the anelastic damping stage, with the increase in the amount of the added SiC particles, the damping performance first increases and then decreases. Moreover, the damping value of the composite material is larger than that of the matrix alloy. In the microplastic deformation stage, the damping properties of the composites and matrix alloys considerably increase with the strain amplitude. [ABSTRACT FROM AUTHOR]

Orthogonal arrays (OAs) are a key research focus in combinatorial design theory and experimental design theory. They play a very important role in an increasing number of interdisciplinary fields, such as computer science, cryptography, multipartite quantum states and quantum information. And the open problems in many fields are closely related to the construction of orthogonal arrays with high strength and large size. At present, some open problems have been solved by using orthogonal arrays. There is an urgent need for developing such orthogonal arrays. This article introduces a general method for obtaining asymmetric orthogonal arrays with high strength. The proposed method is straightforward and constructive. The constructed OAs can be utilized to generate more OAs. Some selective OAs are tabulated for practical applications. [ABSTRACT FROM AUTHOR]

In electrospinning, nanofibers are frequently produced in nonwoven web form. Their poor mechanical properties (below 100 MPa) and difficulty in tailoring the fibrous structure have restricted their applications. However, advanced materials must be highly resistant to both deformation and fracture. By combining electrospinning technology with stretching, we have overcome this disadvantage and demonstrated a polyacrylonitrile nanofiber yarn with a tensile strength of 743 ± 20 MPa. The nearly perfect uniaxial orientation of the fibrils under the stretching process is crucial for the remarkable mechanical properties of the yarn. Additionally, the nanofiber yarn was functionalized by a dip-coating process with silver nanowires (AgNWs), imparting conductive properties. This conductive, high-strength nanofiber yarn demonstrates practical applications in flexible and wearable devices. The presented strategy is versatile and can be adapted to create other high-performance nanofiber yarns, with potential uses in fields such as biomedicine and smart textiles. [ABSTRACT FROM AUTHOR]

Recyclability of polyurethane materials is significant to relieve environmental problems caused by damaged polymers. Inspired by plenty of self‐healing properties based on dynamic covalent bonds. A high mechanical strength and thermally reversible polyurethane adhesive are acquired through co‐polymerization of poly‐1,4‐butylene adipate glycol (PBA), soybean oil‐based polyol (MESO), and toluene diisocyanate (TDI) whose linear polymer chains are constructed by Diels–Alder reaction between furfuryl alcohol (FA) and bismaleimide (BMI), named DAPU. Further, the obtained polyurethane adhesives show great recyclability, mechanical performance (Whose tensile strength can reach 91.7 MPa), and appropriate self‐healing ability through the thermally reversible Diels–Alder covalent bonds and hydrogen bonds between urethane groups, which may pave a way for further development of recyclable materials. [ABSTRACT FROM AUTHOR]

The literature on polyvinyl alcohol (PVA) films is extensive, however, these methods often necessitate intricate synthesis processes or the addition of plasticizers to modify the strength and water solubility of the PVA material. A high‐strength UV radiation‐resistant composite film by chelating Fe3+ with lignin and PVA, which exhibits excellent hydrolysis resistance is developed. This composite film is prepared simply by incorporating a small amount of dealkalized lignin (APPL) and ferric chloride (FeCl3) into PVA through a straightforward composite process. During the scanning test, it is noted that the film exhibits a high density of uniformly dispersed particles, endowing it with efficient ultraviolet absorption capabilities. The infrared and anti‐dissolution tests reveal that the coordination of Fe3+ with lignin imparts an outstanding hydrolysis resistance to the film, obviating the need for any extender, curing agent, acid or base. The tensile fracture strength reaches an impressive 187.81Mpa in the tensile test. UV and indicator card tests unequivocally demonstrate that the film achieves a remarkable 100% anti‐UV efficiency. This Fe3+ chelated lignin/PVA composite film, with its facile preparation, environmental sustainability, high strength, and outstanding anti‐ultraviolet efficiency, can be deployed across diverse applications requiring robust protection against ultraviolet radiation. [ABSTRACT FROM AUTHOR]

Alkali‐activated materials (AAMs) were prepared using tungsten tailings via pressure molding and casting, and their high‐temperature resistances were analyzed. Variations in their compressive strength, gel, and physical phase transformation, pore structure, and morphology at different temperatures were investigated and comparatively analyzed. Results showed that the compressive strength of both AAMs first increased and then decreased with increasing temperature. At 600°C, the pressure‐molded AAM exhibited a considerably higher compressive strength (152.38 MPa) than the cast‐molded AAM (42.05 MPa). Thermogravimetric–differential scanning calorimetry, XRD, and FTIR analyses showed that the pressure‐molded AAM contained more gel phases than the cast‐molded AAM at the same temperature. The gel phase further polymerized and decomposed at high temperatures (>800°C), forming nepheline and zeolite crystals. Mercury intrusion porosimetry and scanning electron microscopy results revealed that pressure molding increases the contact between the gel and unreacted materials, effectively reducing the porosity and densifying the AAM. The pressure‐molded AAM had a considerably smaller pore diameter than the cast‐molded AAM; thus, the former had considerably higher compressive strength. The porosity and pore size of the pressure‐molded AAM gradually increased with the temperature, which polymerized the gel phase and eventually decomposed it; this increased its compressive strength first and then decreased. [ABSTRACT FROM AUTHOR]

Hydrogen bonds (H-bonds) are the most essential non-covalent interactions in nature, playing a crucial role in stabilizing the secondary structures of proteins. Taking inspiration from nature, researchers have developed several multiple H-bonds crosslinked supramolecular polymer materials through the incorporation of H-bond side-chain units into the polymer chains. N-acryloyl glycinamide (NAGA) is a monomer with dual amides in the side group, which facilitates the formation of multiple dense intermolecular H-bonds within poly(N-acryloyl glycinamide) (PNAGA), thereby exhibiting diverse properties dependent on concentration and meeting various requirements across different applications. Moreover, numerous attempts have been undertaken to synthesize diverse NAGA-derived units through meticulous chemical structure regulation and fabricate corresponding H-bonding crosslinked supramolecular polymer materials. Despite this, the systematic clarification of the impact of chemical structures of side moieties on intermolecular associations and material performances remains lacking. The present review will focus on the design principle for synthesizing NAGA-derived H-bond side-chain units and provide an overview of the recent advancements in multiple H-bonds crosslinked PNAGA-derived supramolecular polymer materials, which can be categorized into three groups based on the chemical structure of H-bonds units: (1) monomers with solely cooperative H-bonds; (2) monomers with synergistic H-bonds and other physical interactions; and (3) diol chain extenders with cooperative H-bonds. The significance of subtle structural variations in these NAGA-derived units, enabling the fabrication of hydrogen-bonded supramolecular polymer materials with significantly diverse performances, will be emphasized. Moreover, the extensive applications of multiple H-bonds crosslinked supramolecular polymer materials will be elucidated. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hemicellulose is a renewable and environmentally friendly biomass polysaccharide. However, because of the low polymerization degree, conventional hemicellulose-based hydrogels often have poor mechanical properties, severely restricting their potential applications. This study involved preparation of a novel high-strength conductive hemicellulosebased composite hydrogel, modulated by a Na2SO4 solution. The hydrogel matrix with a physicochemical double cross-linking structure was created by adding polyvinyl alcohol to the chemically crosslinked networks of gelatin and dialdehyde xylan (DAX) to improve the enhancing effect. After being soaked in a 1 M Na2SO4 solution for 24 h, the composite hydrogel's network structure was thicker, as revealed by scanning electron microscopy. Its tensile breaking strength (3.02 MPa) and elongation (330.95%) were much higher than those prior to the treatment. Energy dispersive spectroscopy and X-ray diffraction confirmed that the composite hydrogel had a considerable amount of Na+ and SO42- uniformly dispersed throughout. Additionally, the ionic conductivity of the composite hydrogel was measured at 5.4 x 10-3 S/m, indicating a potential use in the field of super-capacitors. [ABSTRACT FROM AUTHOR]

The classical theory of folded developables suggests that curved crease folding can be applied to sheet metal of high strength to manufacture parts with complex geometries. However, its application has been limited to sheet metals with low strength and requires grooving or perforation of the material at the fold lines. Applying the geometrical concept otherwise remains unexplored despite its potential in sheet metal-intensive industries like automotive, transportation, and construction. The current study introduces a novel sheet metal forming technique called developable forming. The theory of folded developables is applied to design a die tool for flange drawing a developable-shaped steel sheet. A developable connection is produced from high-strength material without resorting to thickness accommodation techniques. Experimental findings establish that the novel process does not follow the premises of the theory of folded developables. New shape effects are observed and the terms curving and coning are introduced to describe these. Additionally, significant redundant strains are identified in the flange, highlighting the different deformation modes in the developable forming process. A higher formability is achieved for a material with limited uniaxial elongation highlighting the need for further investigation on the mechanisms involved in the novel process. [ABSTRACT FROM AUTHOR]

Thermosetting resins have good temperature resistance and high strength and have been widely used as plugging agents in oil fields. However, the current resin materials have high costs, and unmodified thermosetting resins are brittle or have deteriorated properties such as flame retardancy after curing to form a crosslinked network structure. In this study, the resin was modified via physical blending. The curing strength and temperature resistance were used as the main indicators. The resin matrix, curing agent, rheology modifier, and filling materials were modified and formulated optimally to form a high-strength resin gel plugging system. The resin gel system exhibited good fluidity and pumpability. When the shear rate was 200 s−1 at 25 °C, the initial viscosity was 300–400 mPa·s. The viscosity gradually decreased with increasing shear rate, and the apparent viscosity had good long-term stability at room temperature. A contamination test of different types of drilling fluids on the resin gel system showed that this system had good anti-contamination capability and could maintain a high curing strength even after being contaminated. At the same time, the system exhibited good plugging capability. A wedge-shaped fracture with an inlet size of 7 mm and an outlet size of 5 mm was plugged at 12.84 MPa for 10 min without leakage. A sand-filling pipe (with a diameter of 3.8 cm and pipe length of 30 cm) connected to the pipeline with a 6 mm outlet was subjected to a constant pressure of 11.29 MPa and plugged for 8 min before breaking through. Therefore, it exhibited good capability for plugging fissures and cavities. The resin gel leakage-plugging system has significant potential to realize effective plugging of the deep large-fracture leakage layer. [ABSTRACT FROM AUTHOR]

Higher strengths can be achieved using environmentally friendly geopolymer concrete (GPC). Granulated blast-furnace slag (GBFS) and silica fume (SF) were used together in high-strength GPC, and the GBFS + SF mixture was replaced with fly ash at total rates of 5, 10, and 15%. Recycled waste tire wires were added at rates of 1, 2, and 3% by weight. The samples were cured under ambient and oven conditions for 28 days and subsequently tested to characterize their compressive, flexural, and splitting tensile strengths. The test results indicated that adding waste tire wires significantly influenced the samples cured under ambient conditions, leading to a strength increment of up to 45 MPa—an improvement of approximately 50%. The oven-cured samples improved strength by approximately 21%, and the maximum compressive strength peaked at 65 MPa. This result can be used as a positive reference for high-strength concrete. The addition of 3% waste tire wire resulted in a flexural strength of 15 MPa in samples cured under ambient conditions and up to 23 MPa in those cured in an oven. The splitting tensile strength peaked at 16 MPa, which agrees with the bending strength. Scanning electron microscopy and energy-dispersive X-ray analysis were performed on these samples, and the results corroborated these findings, yielding robust supporting evidence for the obtained results. [ABSTRACT FROM AUTHOR]

The beneficiation of low‐grade phosphate ore leads to the production of a substantial quantity of phosphate tailings, thereby not only occupying land but also endangering the environment and potentially posing safety concerns. In this work, extrusion molding, steam‐curing, and calcined phosphate tailings are employed to fabricate lightweight wall materials with superior strength. It is found that the wall material has a special structure of interwoven needle‐like crystals as a way to provide high flexural strength. The main composition of 34.94% phosphate tailings, 36.75% calcined phosphate tailings, 16.64% silica fume, 6.67% anhydrous magnesium sulfate is required to achieve an optimal maintenance process for 4 h of heat preservation at 120 °C saturated vapor pressure environment. The prepared wall materials yield a flexural strength of 24.9 MPa, compressive strength of 18.9 MPa, softening coefficient of 0.81, apparent density of 1.594 g cm−3, and thermal conductivity of 0.269 w/(m K), which meet the requirements of the Chinese standard "Lightweight strip board for building partition walls". Moreover, the calculation revealed that phosphate tailings have a comprehensive utilization rate of 77.23%, effectively mitigating the issues arising from their accumulation and serving as an efficient means of utilizing solid waste derived from phosphate tailings. [ABSTRACT FROM AUTHOR]

In this study, multifibrillar carbon and carbon/ceramic (C/SiCON) fibers consisting of thousands of single nanofibers are continuously manufactured. The process starts with electrospinning of polyacrylonitrile (PAN) and PAN/oligosilazane precursors resulting in poorly aligned polymer fibers. Subsequent stretching leads to parallel aligned multifibrillar fibers, which are continuously stabilized and pyrolyzed to C or C/SiCON hybrid fibers. The multifibrillar carbon fibers show a high tensile strength of 911 MPa and Young's modulus of 154 GPa, whereas the multifibrillar C/SiCON fibers initially have only tensile strengths of 407 MPa and Young's modulus of 77 GPa, due to sticking of the nanofibers during the stabilization in air. Additional curing with electron beam radiation, results in a remarkable increase in tensile strength of 707 MPa and Young's modulus of 98 GPa. The good mechanical properties are highlighted by the low linear density of the multifibrillar C/SiCON fibers (~ 1 tex) compared to conventional C and SiC fiber bundles (~ 200 tex). In combination with the large surface area of the fibers better mechanical properties of respective composites with a reduced fiber content can be achieved. In addition, the developed approach offers high potential to produce advanced endless multifibrillar carbon and C/SiCON nanofibers in an industrial scale. [ABSTRACT FROM AUTHOR]

Tailing is the solid waste discharged from ore after beneficiation. and its accumulation is also increasing, which not only occupies land, but also causes serious environmental pollution and resource waste. The preparation technology of tailings ceramisite was introduced and analyzed systematically. The effects of raw material ratio, auxiliary materials and firing technology on the properties of ceramisite are discussed. The existing problems and solutions were put forward. Then the application of tailing ceramisite in light concrete, water treatment filter material, petroleum proppant. wave absorbing material was introduced. The main research directions for future tailings ceramisite were pointed out, which include light, porous, high strength tailings ceramisite, composite tailings ceramisite preparation technology and expanding the application field of tailings ceramisite. [ABSTRACT FROM AUTHOR]

In high-strength steel (HSS), shear edge failure due to stretch flangeability is a serious problem. Shear edge failure is strongly affected by the cutting methods. As countermeasures, cut-off punching and double punching of the entire circumference have conventionally been considered. However, it has not been shown whether these processes can be applied to the stretch-flange-forming part of the outer circumference of automotive parts. In this study, the effect of the punching allowance and the method of improving the double punching process on the outer circumferences of automotive parts were investigated using hot-rolled HSS sheets. The results of hole expansion tests and observations of shear edge faces and metal flow show that partial double punching reduces the rigidity of the cut-off side and increases the collapse probability. Also, the crack propagation caused by high tensile stress near the upper cutting edge is accelerated. In comparison with double punching of the entire circumference of a 590 MPa-class or 780 MPa-class HSS sheet, in partial double punching, the stretch flangeability is improved and the hole expansion test value is 1.5 times that of double punching when the cut off amount is greater than the thickness. However, it is considered that the stiffness of the cut-off side varies depending on the curvature and the thickness of the plane, and the effect of such variations will be confirmed in a wide range of curvature and thickness in the future. [ABSTRACT FROM AUTHOR]

Lost circulation is a common and complicated situation in drilling engineering. Serious lost circulation may lead to pressure drop in the well, affect normal drilling operations, and even cause wellbore instability, formation fluid flooding into the wellbore, and blowout. Therefore, appropriate preventive and treatment measures need to be taken to ensure the safe and smooth operation of drilling operations. So, it is necessary to conduct in-depth research on the development and performance of the plugging materials. In this study, urea formaldehyde resin with high temperature resistance and strength was used as the main raw material, and the curing conditions were optimized and adjusted by adding a variety of additives. The curing time, compressive strength, temperature resistance, and other key performance indexes of the resin plugging agent were studied, and a resin plugging agent system with excellent plugging performance was prepared. The formula is as follows: 25% urea formaldehyde resin +1% betaine +1% silane coupling agent KH-570 + 3% ammonium chloride +1% hexamethylenetetramine +1% sodium carboxymethyl cellulose. The optimal curing temperature is between 60 and 80 °C, with a controllable curing time of 1–3 h. Experimental studies examined the rheological and curing properties of the resin plugging agent system. The results showed that the viscosity of the high-strength curable resin system before curing remained stable with increasing shear rates. Additionally, the storage modulus and loss modulus of the resin solutions increased with shear stress, with the loss modulus being greater than the storage modulus, indicating a viscous fluid. The study also investigated the effect of different salt ion concentrations on the curing effect of the resin plugging system. The results showed that formation water containing Na+ at concentrations between 500 mg/L and 10,000 mg/L increased the resin's curing strength and reduced curing time. However, excessively high concentrations at lower temperatures reduced the curing strength. Formation water containing Ca2+ increased the curing time of the resin plugging system and significantly impacted the curing strength, reducing it to some extent. Moreover, the high-strength curable resin plugging agent system can effectively stay in various fracture types (parallel, wedge-shaped) and different fracture sizes, forming a high-strength consolidation under certain temperature conditions for effective plugging. In wedge-shaped fractures with a width of 10 mm, the breakthrough pressure of the high-strength curable resin plugging agent system reached 8.1 MPa. As the fracture width decreases, the breakthrough pressure increases, reaching 9.98 MPa in wedge-shaped fractures with an outlet fracture width of 3 mm, forming a high-strength plugging layer. This research provides new ideas and methods for solving drilling fluid loss in fractured loss zones and has certain application and promotion value. [ABSTRACT FROM AUTHOR]

High-strength materials are essential for applications in the structural industry. However, their limited formability restricts broader industrial use. This study proposes a novel methodology to achieve an excellent combination of formability and strength. Surface heterostructuring through laser treatment induces local austenitization on the as-rolled martensitic stainless steel. The resultant bendability was significantly improved, enabling its bending to ∼180° folding while maintaining high tensile strength. Consequently, the present surface heterostructuring suggests achieving the superior combination of strength and formability by tailoring the microstructure specifically to forming. This surface heterostructuring will explore the empty area of the formability-strength relationship. [ABSTRACT FROM AUTHOR]

Through this paper investigation of opening shapein high strength fiber reinforced concrete deep beams without stirrups have been studied to report a comparison between specimens with maximum opening different shape (square, circle) at shear span center in term of load-deflection curve, pattern of crack and stress- strain curve, this paper investigate which specimen has better shape than other. This study done by testing nine specimens one of these is control deep beam without opening and steel fiber while the other are two group each group has four specimens with different opening shape and steel fiber content (0,0.5,0.75,1)%, the opening were square (0.387dX0.387d) while the circle opening is (0.435d) diameter all opening located at the shear span center and reinforced by (3Ø16mm) at the bottom and (2Ø12mm) at the top and two stirrups to prevent local failure. The results showing that the circle opening shape has good stress distribution around opening and get more strength than square opening. The modeling of specimens in abaqus have good agreement with experimental result. [ABSTRACT FROM AUTHOR]

Hydrogel fibers that can be raided possess considerable promise in the realm of flexible electronic gadgets, as they exhibit both exceptional durability and excellent conductivity. Using a continuous coaxial wet-spinning method, we have created a hydrogel long fiber with a core-sheath structure that is both strong, conductive, frost-resistant, and braidable. Hydroxymethylpropyl cellulose (HPMC) added lowconcentration polyvinyl alcohol (PVA) toform the core layer of the fiber he sheaths made of highconcentration PVA. Next, the fibers are submerged in a sodium chloride solution to create PVA@PVA-HPMC hydrogel fibers that exhibit remarkable tensile strength (6.7 MPa), extensive elongation (450%), excellent electrical conductivity (9.23 S/m), and exceptional resistance to freezing temperatures (below −20 °C). The hydrogel fibers are further encapsulated using PSPI copolymers to enhance their environmental stability. Finally, the PVA@PVA-HPMC fibers are applied as flexible sensors to detect human joint movements, and assembled into e-textiles to monitor the positional distribution of pressure. [ABSTRACT FROM AUTHOR]

Toward high‐strength bio‐based polyamide 56 (PA56) fiber, we first in situ precipitate graphene oxide (GO), adipic acid and 1,5‐pentanodiamine together by reaction crystallization in ethanal to obtain PA56 salt/GO particles with well dispersed GO, then prepare PA56/GO nanocomposite with PA56 salt/GO via solvent‐free polymerization including solid‐state prepolycondensation and melt polycondensation. Finally, PA56/GO nanocomposite fiber is prepared by extrusion drawing. With 0.2 wt% GO, the tensile strength of PA56/GO fiber reaches 1050 MPa, which is 3.3 times that of pure PA56 fiber. Furtherly, we add PA56/GO with high GO content to commercial PA56 to prepare the hybrid fiber, of which the tensile strength reaches 1248 MPa. The great improvement is mainly due to the good dispersion of GO in the whole process, which increases the heterogeneous nucleation in favor of higher and oriented PA56 crystallization. Highlights: Bio‐based PA56/GO nanocomposite fiber with 1.2 GPa strength has been prepared.PA56 salt/GO particles with well‐dispersed GO are in situ precipitated.Solvent‐free polymerization is used instead of solution melt polymerization.Well‐dispersed GO results in high and oriented crystallinity of PA56/GO fiber.Tensile strength of PA56/GO fiber is 2.3 times that of commercial PA56 fiber. [ABSTRACT FROM AUTHOR]

In orthopedics and dentistry, there is an urgent need to obtain low-stiffness implants that suppress the stress shielding caused by the use of metallic implants. In this study, we aimed to fabricate alloys that can reduce the stiffness by increasing the strength while maintaining a low Young's modulus based on the metastable β-Ti alloy. We designed alloys in which Ti was partially replaced by Zr based on the ISO-approved metastable β-Ti alloy Ti-15Mo-5Zr-3Al. All alloys prepared by arc melting and subsequent solution treatment showed a single β-phase solid solution, with no formation of the ω-phase. The alloys exhibited a low Young's modulus equivalent to that of Ti-15Mo-5Zr-3Al and a high strength superior to that of Ti-15Mo-5Zr-3Al and Ti-6Al-4V. This strengthening was presumed to be due to solid-solution strengthening. The biocompatibility of the alloys was as good as or better than that of Ti-6Al-4V. These alloys have potential as metallic materials suitable for biomedical applications. [ABSTRACT FROM AUTHOR]

Copyright of Steel Pipe is the property of Steel Pipe Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Currently, the rising environmental concerns caused by nonbiodegradable food packaging materials have promoted the research and development of biodegradable alternatives. Polyvinyl alcohol (PVA) was selected as the substrate, and zinc oxide nanoparticles (ZnONPs) and titanium dioxide nanoparticles (TiO2NPs) were blended and modified with PVA, respectively. Based on the electrostatic spinning technology to prepare fiber membranes with high strength and UV blocking properties for grapes preservation. The study indicated that the tensile strength of PVA fiber membranes increased by 243% and 209% when ZnONPs and TiO2NPs were added at 1%, respectively. Under UV radiation, the PVA/ZnO composite membranes exhibited superior UV absorption than the PVA/TiO2 composite membranes. After conducting TG tests, it was found that the addition of ZnONPs decreased the thermal stability of the fiber membranes, while TiO2NPs could improve the thermal stability. Both composite membranes could extend grapes' shelf life, but the PVA/ZnO composite membranes were more effective at maintaining freshness than the PVA/TiO2 composite membranes. [ABSTRACT FROM AUTHOR]

The use of normal-strength (Grade 60) and high-strength (Grade 80) headed bars as transverse reinforcement can improve the constructability of reinforced concrete structures. However, the ACI 318-19 Code does not allow the use of headed bars as transverse reinforcement in deep beams. ACI 318-19 also does not allow engineers to take advantage of the increased yield strength of Grade 80 reinforcement for use as shear reinforcement. This paper presents an analytical evaluation of shear-critical deep beams that use high-strength headed reinforcement. Six recently conducted largescale experiments are modeled using the two-parameter kinematic theory, the nonlinear finite element tool VecTor2, and strut-and-tie methods described in codes. The predictions are compared with experimental results. A parametric study is conducted to evaluate the influence of the quantity of transverse reinforcement and yield stress of the transverse reinforcement on the response of shearcritical deep beams. [ABSTRACT FROM AUTHOR]

Using normal-strength (Grade 60) and high-strength (Grade 80) headed bars as shear reinforcement can improve the constructability of reinforced concrete structures. However, the ACI 318-19 Code does not allow the use of headed bars as transverse reinforcement in deep beams. Similarly, ACI 318-19 does not allow engineers to take advantage of the increased yield strength of Grade 80 reinforcement for use as shear reinforcement. Therefore, to investigate the performance of headed and high-strength transverse reinforcement on the shear behavior of deep beams, a series of six large-scale specimens were tested to failure. The member response, including crack widths and strains in transverse reinforcement, were examined. The results show that deep beams containing headed and high-strength transverse reinforcement performed well compared to companion tests using conventional reinforcement. [ABSTRACT FROM AUTHOR]

Given the escalating prevalence of electromagnetic pollution, there is an urgent need for the development of high‐performance electromagnetic interference (EMI) shielding materials. Herein, wood‐based electromagnetic shielding materials have gained significant popularity due to their exceptional performance as building materials. In this study, a novel wood‐based composite with electromagnetic shielding properties is developed. Through the in situ growth of zeolitic imidazolate framework‐8 (ZIF‐8) crystals on wood fibers, coupled with uniform integration of carbon nanotubes (CNTs), a multifunctional composite named ZIF‐8/Poplar‐CNT composite is synthesized via a one‐step thermoforming process. The incorporation of CNTs endows the composites with excellent EMI shielding effectiveness (EMI SE). Among these elements, despite ZIF‐8 crystals not possessing intrinsic electromagnetic shielding functionality, their distinctive dodecahedral structure proves adept at scattering and reflecting electromagnetic waves within the composites, further improving the electromagnetic shielding effect. Hence, the ZIF‐8/Poplar‐CNT composite (56.95 dB) has ≈10 dB higher EMI SE compared to that of the composites without ZIF‐8 crystals. Meanwhile, ZIF‐8 crystals endow the materials with excellent tensile strength (54.84 MPa, enhanced by 4 times). Moreover, the introduction of Zn2+ provides superior antibacterial properties. The potential applications of ZIF‐8/Poplar‐CNT composites extend to diverse areas such as building decoration, electronic products, and medical equipment. [ABSTRACT FROM AUTHOR]

Polymer-based actuators have gained extensive attention owing to their potential applications in aerospace, soft robotics, etc. However, poor mechanical properties, the inability of multi-stimuli response and programmable deformation, and the costly fabrication procedure have significantly hindered their practical application. Herein, these issues are overcome via a simple and scalable one-step molding method. The actuator is fabricated by hot-pressing commercial unidirectional carbon fiber/epoxy prepregs with a commodity PC membrane. Notable CTE differences between the CF and PC layers endow the bilayer actuator with fast and reliable actuation deformation. Benefiting from the high strength of CF, the actuator exhibits excellent mechanical performance. Moreover, the anisotropy of CF endows the actuator with design flexibility. Furthermore, the multifunction of CF makes the actuator capable of responding to thermal, optical, and electrical stimulation simultaneously. Based on the bilayer actuator, we successfully fabricated intelligent devices such as light-driven biomimetic flowers, intelligent grippers, and gesture-simulating apparatuses, which further validate the programmability and multi-stimuli response characteristics of this actuator. Strikingly, the prepared gripper possesses a grasping capacity approximately 31.2 times its own weight. It is thus believed that the concept presented paves the way for building next-generation robust robotics. [ABSTRACT FROM AUTHOR]

In this work, pure copper and copper-tungsten (Cu-W) surface composite is produced using a single pass friction stir processing (FSP) with an intention to enhance the hardness and wear resistance without impairing electrical conductivity. FSP is performed by changing the traverse speed from 50 to 200 mm/min and at a constant tool rotational speed of 600 rpm. The samples extracted from the stir zone are characterized for their microstructure, hardness, wear behaviour and electrical conductivity. The average grain size, at the stir zones, was significantly reduced (from 40 to 3 µm) after FSP. In the case of pure copper, the grain size decreased from 9 to 3 µm with an increase in traverse speed, however, grain size increased from 4 to 6 µm in the case of Cu-W composite. The hardness of FSP'ed Cu and FSP'ed Cu-W surface composite was increased in the order of 52% and 130% compared to the unprocessed copper. The wear rate significantly reduced after FSP also with an addition of W particles. A negligible reduction (1.83% IACS) in electrical conductivity was noticed for both Cu and Cu-W after FSP. This study demonstrates that the FSP is an effective approach to improve the surface mechanical properties of Cu without much impairing the electrical conductivity. [ABSTRACT FROM AUTHOR]

This research reports the investigations of threshold reactivity limit of blends of pegmatite with different calcined clays as well as the influence of calcined clay source on the geopolymerization kinetic, microstructural, and physicomechanical properties of feldspathic mineral-based inorganic polymer composites. These composites were designed from 85 to 94 wt% of the solid solution of pegmatite and calcined clay. The three-point flexural and compressive strengths, porosity, and microstructure as well as heat evolution rate of geopolymerization reactions of resulting composites were affected by the type of calcined clay. The four calcined clays provided the highest mechanical properties of the composites when added in the range of 12-15 wt%. Specifically, the values of flexural and compressive strengths ranged from 32 to 34 MPa and 101 to 105 MPa, respectively, for geopolymer composites with 15 wt% of metakolin added, while they ranged from 38 to 42 MPa and 106 to 107 MPa with 12 wt% of meta-hallosyte added. The polycondensation/polymerization process of calcined clay developed sufficient amounts of N-A-S-H and polysialate geopolymer to cover the incongruently dissolved fine particles of pegmatite. The resulting microstructure was dense and compact with the lower cumulative pore volume at about 91 mm3/g. It was concluded that designing the pegmatite/clay-based geopolymer composites with high mechanical strengths and low porosity resulted in sustainable, low energy consumption and environmental-friendly materials for civil engineering. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a load‐bearing tissue, natural cartilages possess a compressive stress above 50 MPa, a water content around 60%, and a friction coefficient (FC) less than 0.1, which remains difficult for synthetic materials to realize. Herein, a facile strategy was reported to achieve this goal. The hydrogel was obtained through a three‐step strategy from polyvinyl alcohol (PVA), chitosan (CS), sodium carboxymethyl cellulose (CMC‐Na), lecithin (LS), and deionized water. First, freezing–thawing the aqueous solution of PVA and CS three times generated the precursor gel. Second, immersing it in aqueous solution of CMC‐Na to form multiple linkages (hydrogen bonds, ionic interactions, and crystallize domains). Third, it was coated with LS to form a lubrication layer. Due to the synergy of dynamic interactions, the compressive stress was 115 MPa, superior to most tough hydrogels. Owing to existence of LS, the FC was 0.03, better than the requirement for artificial cartilage. Remarkably, the FC remained stable within 50,000 wear cycles. On account of the reversible break/reformation of physical linkages, the creep recovery efficiency was 93%. The raw materials are all biocompatible and the fabrication process exclude the adoption of toxic additives. All of these features make it an ideal material for cartilage replacement. [ABSTRACT FROM AUTHOR]

Ion‐selective membrane embedded in a reverse electrodialysis system can achieve the conversion of osmotic energy into electricity. However, the ingenious design and development of pure polymer membranes that simultaneously satisfy excellent mechanical strength, long‐term stability, high power density, and increased testing area is a crucial challenge. Here, high‐strength, thin PBO nanofiber membranes (PBONM) with 3D nanofluidic channels and a thickness of 0.81 µm are prepared via a simple vacuum‐assisted filtration technology. The thin PBONM exhibits excellent mechanical properties: stress of 235.8 MPa and modulus of 16.96 GPa, outperforming the state‐of‐the‐art nanofluidic membranes. The obtained PBONM reveals surface‐charge‐governed ion transport behavior and high ion selectivity of 0.88 at a 50‐fold concentration gradient. The PBO membrane‐based generator delivers a power density of 7.7 and 40.2 W m−2 at 50‐fold and 500‐fold concentration gradient. Importantly, this PBONM presents excellent stability in response to different external environments including various saline solutions, pH, and temperature. In addition, the maximum power density of PBONM reaches up to 5.9 W m−2 under an increased testing area of 0.79 mm2, exceeding other membrane‐based generators with comparable testing areas. This work paves the way for constructing high‐strength fiber nanofluidic membranes for highly efficient osmotic energy conversion. [ABSTRACT FROM AUTHOR]

The requirements of low weight and high strength are often contradictory in the design and production of manned/unmanned submersibles. In this paper, a novel structure that combines fiber-reinforced composites and buoyancy materials was proposed to solve this contradiction. These two materials in this structure can cooperate and obtain good compressive properties and low densities. A theoretical model of the compressive strength of this combined structure is proposed. Compression experiments were carried out on six groups of samples. The experimental results show that the compressive capacity of the combined structure is greater than the sum of the compressive capacity of buoyancy material and FRP pipe. The stress distribution of the combined structure under uniaxial pressure is simulated through a finite element model. The numerical simulation results and theoretical predictions show good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

In this study, aiming at the problem of low strength and high creep caused by medium–low modulus flexible resin based on the formulation design idea of high-molecular-weight epoxy resin (E12)-reinforced flexible epoxy-terminated urethane resin (EUR), a flexible epoxy prepreg resin with high strength and low bending creep was prepared to be suitable for hot melt processing technology. Flexible EUR was synthesized by grafting flexible polyurethane segments onto the epoxy side chain by urethane bonding. By adjusting the ratio of E12 and EUR, the effects of different ratios of the two components on the mechanical properties and viscoelasticity of the resin were systematically studied with dicyandiamide as the latent curing system. Research has found that when the E12 content is between 20%wt and 40%wt, the resin system has the best coating viscosity at 65 °C to 85 °C. The molecular weight and the content of aromatic heterocyclic groups of the resin determine the strength and creep behavior of the resin. When the content of E12 in the system is less than 50%wt, modulus and strength increase linearly, but after more than 50%wt E12 content, the modulus is almost unchanged and the strength begins to decrease. By increasing the content of E12 in the resin, the creep behavior of the resin is greatly reduced. When the content of E12 increases to 50%wt, the bending creep is the lowest. [ABSTRACT FROM AUTHOR]

As global urbanization flourishes, the adverse effects on the environment also incredibly increase. This urbanization leads to the evolution of construction and building materials. To meet the requirements of eco-balanced construction materials without compromising their original properties, many evolutions of concrete are in practice nowadays. One such evolution of concrete is geopolymer concrete. The objective of the current study is to produce high-strength geopolymer concrete using ground granulated blast furnace slag (GGBS), metakaolin (MK), and nano-silica (NS) in ambient-cured conditions. The influence of nano-silica in the geopolymer concrete is evaluated by workability, setting time, mechanical strength, durability properties, and microstructural analyses, which include scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and correlation analysis. In this research, the effect of nano-silica on formulating the equation for modulus of elasticity was determined. Nano-silica was replaced at a percentage of 1, 2, and 3% of the binder material. It is summarized that the molar ratios and properties of the precursor materials are the defining factors in altering the systems of geopolymer concrete. The highest strength of 89.4 MPa at 28 days of ambient-cured concrete with outstanding durability performance was achieved. [ABSTRACT FROM AUTHOR]

Cellulosic-based materials such as hemp fabric and paper have combined characteristics of renewability, biodegradability, flexibility, and recyclability. However, regular products are not suitable for use in unconventional applications due to inherent limitations, and accordingly, enabling new capabilities is a necessity. To this end, the conversion of regular hemp fabric and paper into high-strength products with hydrophobic function via surface engineering was explored. The fluorinated waterborne polyurethane (FWPU) emulsions were first synthesized as functional coatings by in-situ polymerization. The structure and properties of the FWPU emulsion and film were characterized by FTIR, XRD, SEM, TG, and XPS. The results showed that the grafting of perfluorooctanol imparts WPU film excellent hydrophobicity, and the water contact angle increases from 71.2° to 105.9°. After the FWPU coating, the water contact angles of the hemp fabric and paper increase from 0° to 117.1° and 112.8°, respectively. Quite encouragingly, the coating generation of waterborne polyurethane-derived functional additives led to the increase of mechanical strength by more than 23% and 82%, in the case of qualitative filter paper and hemp fabric. Meanwhile, the folding strength of filter paper is increased by 132 times. Overall, this functionalized waterborne polyurethane coating would direct paper and hemp fabric toward diversified applications. [ABSTRACT FROM AUTHOR]

The strength and electrical conductivity balances in Cu/martensite (α') steel multilayered sheets with various volume ratios were evaluated. Furthermore, the measured tensile properties and electrical conductivity were compared with the values estimated from the rule of mixtures, and the reason for the difference between the measured and estimated values was discussed based on the deformation and fracture behaviors. The multilayered sheets exhibited excellent strength-electrical conductivity balances superior to those of conventional Cu alloys, and their strength and electrical conductivity can be controlled over a wide range by changing the volume fraction of α' steel. The electrical conductivities of the multilayered sheets with different volume ratio were approximately identical to the estimated values based on the rule of mixtures. However, the ultimate tensile stresses of the multilayered sheets with lower volume fractions of the α' layer were slightly lower than the estimated values. A significant strain concentration occurred within the α' steel layer in the multilayered sheet with the lowest volume fraction of α' steel. Furthermore, cracks and/or voids were formed in the α' steel layers even during the uniform-deformation stage. Therefore, the early fracture of the α' steel layers caused lower ultimate tensile stresses in the multilayered sheet with low fractions of the α' steel than the estimated value based on the rule of mixtures. [ABSTRACT FROM AUTHOR]

The current interest in Al-Mg-Sc-Zr alloy fabricated by powder bed fusion-laser beam (PBF-LB) is centered around excellent mechanical property without taking into account its corrosion behavior. In this work, gas-atomized Al-Mg-Sc-Zr alloy powder was manufactured by PBF-LB. The influence of heat treatment on microstructure, phase evolution, mechanical properties, and electrochemical corrosion behaviors were investigated and microstructure–property relationship was established to obtain high-performance alloy. The result suggests that the sample heat treated at 350°C for 4 h possesses highest mechanical properties, but is more susceptible to corrosion. When heat treatment temperature reaches 400°C, the loss of coherency for Al3(Sc, Zr) precipitates decreased the strength, but the Al6Mn phase is corroded as cathode instead of the α-Al matrix, thereby inhibiting the occurrence of pitting corrosion. The specimen heat treated at 300°C for 4 h exhibited high strength and high elongation as well as superior corrosion resistance. [ABSTRACT FROM AUTHOR]

The nature creates many biomaterials such as spider silk which exhibits a combination of stiffness, strength and toughness. However, most of synthetic unfilled materials suffer from a trade‐off between toughness and stiffness. Inspired by the structure of spider silk but beyond it, we proposed a novel molecular design to achieve transparent unfilled waterborne polyurethane (WPU) with simultaneously enhanced stiffness (280.9 MPa), tensile strength (25.1 MPa) and toughness (140.0 MJ/m3) as well as good elasticity (710%). The designed WPU comprised homogeneous continuous phase (soft segments) and diverse H‐bonds (hard segments) dispersed in it. The increase of rigid molecular chain content and H‐bonds contributed to the high stiffness of WPU. Furthermore, the mismatch of stiffness between hard domains and soft segments might promote crack deflection and branching, which endowed the robust WPU with fracture energy of 81.16 kJ/m2. The robust WPU film could be healed to recover most of its original mechanical properties (strength for 24.4 MPa and elongation for 610%) under heating. In addition, the WPU films demonstrated good antibacterial performance against Staphylococcus aureus and Escherichia coli after chlorination. [ABSTRACT FROM AUTHOR]

The traditional thermoset polyurethanes (PUs) can be recycled through the dynamic carbamate bonds under specific conditions. However, there is limited research on the structural evolution and property changes of these PUs before and after recycling. Herein, we designed and fabricated a thermoset polyurethane network (PCU) using polyhexamethylene carbonate diol (PHMC‐diol) as soft segments, and isophorone diisocyanate (IPDI) and glycerol (GLY) as hard segments. Through careful formulation design, the PCU demonstrated colorless transparency (with up to 86% transmission), shape memory properties, and reprocessing capabilities, all achieved without introducing other dynamic covalent bonds. Furthermore, the PCU exhibited excellent mechanical properties, boasting a tensile strength of 59.2 ± 3.7 MPa and the elongation at break of 674.8 ± 37.3%. Of particular interest, the PCU samples displayed solid‐state plasticity and impressive shape memory performance, with shape fixity and recovery ratios exceeding 90%. Leveraging the combination of solid‐state plasticity and shape memory, the PCU samples demonstrated the ability to achieve arbitrary shape manipulations. Upon recycling, it was observed that the cross‐linking density of the PCU samples decreased, resulting in the formation of byproducts and subsequently leading to a reduction in tensile strength. Nonetheless, the PCU samples prepared in this study exhibit potential as thermadapt shape memory and recyclable materials. [ABSTRACT FROM AUTHOR]

In this investigation, an attempt was made to develop a new high-strength and high-ductility aluminum metal–matrix composite. It was achieved by incorporating ceramic reinforcement into the metal which was formed in situ from a polymer by pyrolysis. A crosslinked PMHS polymer was introduced into commercially pure aluminum via friction stir processing (FSP). The distributed micro- and nano-sized polymer was then converted into ceramic particles by heating at 500 °C for 10 h and processed again via FSP. The produced composite showed a 2.5-fold increase in yield strength (to 119 MPa from 48 MPa) and 3.5-fold increase in tensile strength (to 286 MPa from 82 MPa) with respect to the base metal. The ductility was marginally reduced from 40% to 30%. The increase in strength is attributed to the grain refinement and the larger ceramic particles. High-temperature grain stability was obtained, with minimal loss to mechanical properties, up to 500 °C due to the Zenner pinning effect of the nano-sized ceramic particles at the grain boundaries. Fractures took place throughout the matrix up to 300 °C. Above 300 °C, the interfacial bonding between the particle and matrix became weak, and fractures took place at the particle–matrix interface. [ABSTRACT FROM AUTHOR]

Owing to the inferior dispersibility of boron nitride nanosheets (BNNSs) and weak interfacial interaction with the matrix, the performance of BNNS‐based composites is usually far below theoretically predicted values. Here, binary multiscale BNNSs (LDH‐BNNSs) fillers are synthesized through in situ growth of layered double hydroxide (LDH) on the BNNSs' surfaces. LDH‐BNNSs with a multiple mosaic interface show superior dispersion of nanosheets in matrix and extraordinary filler‐matrix bonding. Density functional theory simulations reveal the stable dispersion mechanism of LDH‐BNNSs. Moreover, the bio‐based poly(ethylene furandicarboxylate) composites with 0.2 wt% LDH‐BNNSs loading exhibit simultaneous improvements in tensile strength (≈140 MPa), Young's modulus (≈6.5 GPa), toughness (≈2.0 MJ m−3), and gas barrier properties. Regulation of the interfacial structures of binary multiscale BNNSs significantly increases the filler utilization of the nanosheets, leading to extraordinary stress transfer efficiency and a physical shielding effect. Therefore, this simple, efficient, and novel strategy has promised in enhancing composite performance, and it provides a novel way to develop strong, tough, and high‐barrier bio‐based polyester composites. [ABSTRACT FROM AUTHOR]

The thermal conductivity of magnesium alloys is increasingly required for fast heat dissipation in the automotive and electronic fields. However, the methods for mechanical property improvement such as grain refinement and alloying tend to deteriorate their thermal conductivity. In this work, a novel low-alloy Mg–2Ga–0.6Ca–0.6Ce alloy exhibits a surprisingly good combination of high strength and high thermal conductivity compared with the other samples. The wrought alloys are of small grain sizes (< 2 μm), have high yield strength (> 272 MPa) and exhibit excellent thermal conductivity (> 143 W·m−1·K−1). The as-extruded alloy exhibits excellent yield strength (272 MPa) and high thermal conductivity (144.6 W·m−1·K−1) at room temperature. After 30% rolling, the yield strength is further increased to 283 MPa, and the thermal conductivity is slightly reduced to 143.2 W·m−1·K−1. The effects of Ca and Ce addition on mechanical properties and thermal conductivity are analyzed from dislocation density, dynamic recrystallization fraction (fDRX), average grain size (dDRX) and texture characteristics. The higher yield strength can be attributed to the combination of grain boundary strengthening, dislocation strengthening and second phase strengthening. Moreover, the addition of Ca and Ce can obviously reduce solute Ga atoms in α-Mg, which is the key to high thermal conductivity. Therefore, adding two alloying elements, Ca and Ce, significantly improves both tensile properties and thermal conductivity. [ABSTRACT FROM AUTHOR]