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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]

Ionogels as ionic conductors have attracted extensive attention due to their excellent ionic conductivity, good thermal and electrochemical stability, and favorable non‐volatility compared to conductive hydrogels. However, ionogels with excellent conductivity usually suffer from low strength and modulus. Herein, a facile yet effective strategy by compositing aligned cellulose fibers with ionogels is presented to achieve superior mechanical properties and high ionic conductivity. The triple hydrogen bond networks enable the ionic conductors to possess superhigh tensile strength (≈32.75 MPa) and Young's modulus (≈1354 MPa), as well as exhibit excellent crack‐resistant properties. Meanwhile, the ionic conductors with aligned cellulose fibers provide oriented hierarchical micro‐ and nanochannels for accelerating ion transport and thus can obtain a high ionic conductivity. Moreover, the ionic conductors exhibit high optical transparency (≈92%), good adhesion, and favorable flexibility. This work provides a straightforward and effective strategy for the development of high‐strength, high‐conductivity, and crack‐resistant ionic conductors. [ABSTRACT FROM AUTHOR]

Highlights To meet the urgent demands of aerospace vehicle upgrades and replacements, which require honeycomb structures with higher specific strength and environmental adaptability, the development of lightweight and high‐strength short‐cut carbon fiber reinforced polymer (S‐CFRP) honeycombs is an effective approach. First, this study designed a hot pressing process, which was utilized for the fabrication of both short‐cut CF paper and S‐CFRP honeycomb. Second, a finite element model was established to predict the mechanical performance of the S‐CFRP honeycomb. Finally, mechanical experiments were conducted on the S‐CFRP honeycomb and the failure factors were analyzed. The S‐CFRP honeycomb features cell edges as low as 2.75 mm in length, with a density reduced to 47.6 kg/m3, achieving the coexistence of small cell edge length and low density in the honeycomb structure. Compared with the aramid honeycomb of 48.06 kg/m3 from Hexcel Corporation, the compressive strength of the S‐CFRP honeycomb was increased by 21%, and the shear strengths in the L and W directions were improved by 42% and 59%, respectively. This study provides a fabrication method and simulation model for low‐cost, lightweight, high‐strength S‐CFRP honeycombs, which has significant engineering value for enhancing the weight reduction efficiency and the mechanical performance of aircraft structures. A low‐cost, high‐strength short‐cut CF paper has been prepared. An S‐CFRP honeycomb, lightweight and with small cells, has been made. The strength of S‐CFRP honeycombs exceeds that of aramid ones. The failure factors of the S‐CFRP honeycomb were analyzed. Performed accurate mechanical simulation analysis on S‐CFRP honeycomb. [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]

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]

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]

Ultrafine grained (UFG) n-C/Al composite bulk was obtained by mechanical milling and hot extrusion with petroleum coke utilized as carbon source. After extrusion, n-C sheets got dispersed and distributed in grain interiors or at grain boundaries. The tensile strength and corresponding thermal conductivity reached 407 ± 3 MPa and 216 ± 1.6 W m−1 K−1.

Gradient microstructures (GMs) help to improve simultaneously the strength and ductility of metallic materials; therefore, GMs have attracted more and more interest in recent years. The current researches on GMed metals mainly focus on the quasi-static mechanical properties, whereas the dynamic mechanical behavior of GMed metals remains mysterious. Here, GMed pure aluminum was prepared by cryogenic pre-torsion. Split Hopkinson tensile bar (SHTB) tests show that GMs can improve the dynamic tensile strength without the sacrifice of final elongation. Quantitative microstructural characterization indicates that the gradients of dislocation density, grain size and precipitate volume fraction contribute to the excellent dynamic mechanical properties in GMed aluminum. A modified Johnson-Cook model based on multiple GMs was proposed to describe the dynamic mechanical behavior of GMed metallic materials. Systematical finite element simulations were further conducted to reveal the underlying mechanisms during SHTB tests of GMed aluminum bar. The gradient of yield flow stress contributes the improvement of dynamic tensile strength. The extra hardening from multiple GMs and the occurrence of dynamic recrystallization (DRX) promote the increase of final elongation.

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]

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]

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]

For decades, solid solution strengthening with up to 9 wt.% Ni has been the only successful strategy to obtain high strength and high impact toughness in bcc‐structured (ferritic or tempered martensitic) cryogenic steels. Until now coherent nano‐precipitates, an effective strengthening agent at room temperature, cannot be used to improve properties at cryogenic temperatures. Here, a new type of Mo‐rich nano‐B2 precipitates formed in a 6.5 wt.% Ni steel upon doping with 0.2 wt.% of Mo is reported. These precipitates are not only fully coherent with the matrix but are also shearable at 77 K. A high precipitate number density in excess of 2 × 1024 m−3 has been achieved by an industrially feasible process optimization, which brings both the cryogenic strength and impact toughness of the steel to the same levels as those of 9Ni steels. The Mo‐rich B2 precipitation strengthening, therefore, opens a new avenue for the design and development of low‐cost high‐performance cryogenic steels. [ABSTRACT FROM AUTHOR]

Fiber‐shaped supercapacitors are pivotal for wearable device advancement, yet they struggle to achieve both high strength and energy density, hindering their daily practicality in wearable electronic devices. In this study, a sugar‐derived carbon‐based fiber with a core‐sheath structure is designed to enhance the overall performance of fiber supercapacitors. The porous multi‐walled carbon nanotubes (MWCNTs) sheath is bonded by sugar‐derived carbon （SDC）, which effectively prevents aggregation between the MWCNTs, providing a large adsorption surface for the fiber, consequently yielding excellent electrochemical performance, with a specific capacity of 236.7 F cm−3. The sugar‐derived core fibers function as the current collector for the fiber electrode, contributing significantly to the mechanical properties (213 MPa). The assembled fiber‐shaped supercapacitors demonstrate outstanding energy density (5.67 mWh cm−3 at power density of 45 mW cm−3) and flexibility, which can provide stable energy for various electronic devices and has great potential for application in wearable devices. [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]