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With the continuous miniaturization and highly integrated development of modern electronics, thermal management materials with high thermal conductivity, good electrical insulating and flexibility are highly desired for the effective heat dissipation to maintain the reliable operations of electronic devices. However, enhancing thermal conductivity generally causes the deterioration of their mechanical properties and electrical insulation. Herein, combining the deformability of Galinstan-based liquid metal (LM) and good film-forming property of bacterial cellulose (BC), a series of thin and flexible boron nitride-based composite (BC/BNNS-LM) films was prepared via a facile vacuum-assisted filtration route. Benefiting from the directional arrangement of BNNS nanosheets, as well as gap-filling and bridging effects of deformable LM droplets, the resultant BC/BNNS-LM ternary nanocomposite film not only presents a high in-plane thermal conductivity of 66.1 W/m·K but also achieves excellent mechanical strength, flexibility and good dielectric property. These desirable properties confirm that the fabricated nanocomposite films have significant potential for effective heat dissipation in high-power-density electronics. [ABSTRACT FROM AUTHOR]

This research contributes to the industry’s shift toward becoming a technology-intensive sector. It offers practical recommendations for knitwear designers and educators, helping to foster the sustainable growth of the knitwear industry. This study focuses on evaluating the mechanical properties and wearability of men’s seamless pullover knitwear based on different shoulder designs. The wearability evaluation included both aesthetic appraisal and an analysis of motion suitability. This study offers the following practical design recommendations for the production of seamless knitwear. First, the Set in B design exhibited the best mechanical properties, with superior tensile strength and elongation recovery. Second, the three-dimensional (3D) sleeve design was found to be the most aesthetically superior. Finally, the Epaulet design was found to offer the highest level of comfort during wear. By integrating this technology with other industries, the knitwear industry could evolve into a high-value, sustainable industry. [ABSTRACT FROM AUTHOR]

Highlights In this paper, the mechanical properties and vibration characteristics of Carbon‐Glass Hybrid Fiber Composites (CGHFC) are experimentally investigated with varying axial directions and blending ratios. The experimental results demonstrate a significant increase in the tensile strength of the CGHFC with an increasing content of carbon fibers. The biaxially CGHFC exhibits a maximum static tensile strength of 413.27 MPa in the 0° direction and 466.33 MPa in the 90° direction, surpassing both the quadratic and uniaxial directions. Notably, compared to biaxially oriented glass fiber material, the tensile strength of CGHFC is enhanced by 44.36%, thereby significantly improving its overall performance, making them particularly suitable for blade structures subjected to simultaneous tensile and vibratory loads. By optimizing the fiber orientation and blend ratio, the CGHFC provides good vibration control and fatigue resistance while ensuring high strength, thus maximizing the overall performance and service life of the blades. The results of this paper provide important data and theoretical support for the selection and design of wind turbine blade materials and help to promote the development of composite materials in wind turbine blade structure and design. CGHFCs show enhanced tensile strength with more carbon fibers. Biaxial CGHFCs have max tensile strength at 0° and 90° directions. CGHFCs' strength improves by 44.36% over glass fiber materials. Optimized CGHFCs offer superior vibration control and fatigue resistance. Research supports wind turbine blade material innovation. [ABSTRACT FROM AUTHOR]

Fabrication of crystalline, robust covalent organic framework (COF) membranes based on disorder‐to‐order strategy is promising yet highly challenging. Herein, a microwave‐assisted method for fabricating COF membranes is proposed. Initially, monomers polymerize rapidly on the surface of porous Al2O3 substrate at room temperature to form an amorphous pristine membrane. Subsequently, a microwave field is exerted to trigger fast crystallization, acquiring a crystalline COF membrane within 60 min. The amorphous pristine membrane exhibits a high dissipation factor, indicating excellent microwave absorption capability, which accelerates the dynamic reversible reactions during the microwave treatment and thus ensures a rapid transition from the amorphous to the crystalline state. Owing to the high‐crystallinity and robust structure, the COF membranes exhibit high rejection rates for solute molecules with molecular weights exceeding 700 Da (e.g., Evans blue: 98.7%) and high solvent permeance for organic solvents (e.g., ethanol: 87.8 Lm−2h−1 bar−1, n‐hexane: 222.3 Lm−2h−1 bar−1). Surprisingly, the COF membranes exhibit superior mechanical properties, with Young's modulus of 33.91 ± 3.94 GPa, outperforming previously reported polycrystalline COF membranes and are close to those for inorganic zeolite membranes. The microwave‐assisted COF crystallization method opens a new avenue to fabricating a variety of crystalline membranes for advanced separations. [ABSTRACT FROM AUTHOR]

This study presents novel mechanochemical methods for the synthesis and chemical modification of bismuthene nanosheets (BINS) using a high‐speed blender and planetary ball milling. Atomic force microscopy (AFM) measurements confirmed successful exfoliation of 1.5‐nm BINS. Epoxy/BINS nanocomposites exhibited enhanced mechanical properties, thermal stability, and chemical resistance. Chemical modification via ball milling improved the interface and dispersion of BINS within the epoxy matrix, leading to significant enhancements in mechanical performance and chemical resistance. Compared to neat epoxy, at 0.75 vol% m‐BINS, Young's modulus, impact strength and fracture toughness KIC were respectively enhanced by 30%, 88.6%, and 144.4% while these increments were 10%, 55.7%, and 97.8% for pristine BINS‐based epoxy nanocomposite. A 3D finite element model of the impact test of the nanocomposite was developed to predict its behavior under high‐strain rate loadings; the numerical model showed high agreement with experimental measurements. Epoxy/m‐BINS nanocomposites demonstrated exceptional chemical resistance, attributed to the small lateral dimensions of m‐BINS, which fill the spaces between cross‐linked epoxy molecules and uniformly distribute within the matrix. These findings highlight the crucial role of interface and dispersion in defining the mechanical properties of nanocomposites. Overall, this study provides a facile and scalable method for synthesizing and modifying bismuthene, showcasing its potential for developing functional polymer nanocomposites. Highlights: Bismuthene nanosheets & modified BINS (m‐BINS) are prepared by eco‐friendly method.m‐BINS is ~1.5 nm thick and ~0.5 μm wide.m‐BINS shows good dispersion and strong interface adhesion within epoxy matrix.Impact strength and KIC of epoxy/m‐BINS nanocomposite are enhanced by 88.6% and 144.4%.Numerical model for impact strength is developed to predict behavior at high‐strain rate. [ABSTRACT FROM AUTHOR]

The interaction properties can be significantly improved by using conjugated polymers with aromatic rings for carbon nanotube (CNT)‐reinforced composites. In this study, we investigated the influence of the molecular structure of the polyimide (PI) conjugated polymer on the mechanical properties and interfacial characteristics of CNT/PI composites. To that end, nanocomposites composed of aligned multi‐walled carbon nanotubes (MWNTs) and PI with three different molecular structures were examined. Tensile tests, small‐angle x‐ray scattering (SAXS), and molecular dynamics (MD) simulations were conducted, which revealed significant variations in the tensile properties among the three aligned MWNT/PI nanocomposites. The SAXS analyses indicated that MWNT/BPDA‐PDA had the largest interfacial specific surface area, as corroborated by the MD simulation results, which further demonstrated that the rigidity of the molecular structure influenced the extent of wrapping the PI chains around MWNTs. A highly rigid molecular chain hindered the intrachain folding of the PI chain, facilitating better wrapping of the MWNTs and a larger interfacial area. The MWNTs induced conformational changes in the PI chain owing to π–π stacking. Hermans orientation factor revealed that BPDA‐PDA exhibited the highest degree of orientation with MWNTs, whereas BTDA‐MPD displayed the greatest extent of MWNT‐induced conformational changes. The calculated interaction energy confirmed that MWNT/BTDA‐MPD exhibited the strongest interface strength (−41.50 Kcal/mol/nm2), which was 36.32% and 43.03% higher than that of MWNT/BPDA‐ODA and MWNT/BPDA‐PDA, demonstrating its superior tensile properties. This study provides insights into the interfacial characteristics between conjugated polymers and CNTs, which are essential for designing interfaces and developing high‐performance nanocomposites. Highlights: Interfacial interaction between polyimide and aligned carbon nanotubes was investigated.Modulation by polyimide structures on the mechanical property of composite was revealed.The rigidity of the polyimide hinders the folding and facilitates the wrapping.The interfacial interaction induces molecular orientation in polyimide can be observed by molecular dynamic simulation. [ABSTRACT FROM AUTHOR]

Multifunctionalization of electromagnetic wave absorbing materials (EMWAMs) presents a promising avenue for their application in complex scenarios. However, the effective integration of multiple supplementary functions into EMWAMs continues to pose a significant challenge. Herein, a novel nanofiber elastomer (NFE) incorporating multicomponent inorganic FeS2/S,N co‐doped carbon nanofibers (NFs) and organic component (Ecoflex) are designed and synthesized. The sulfur doping ratios and species can be effectively modulated via controlling the amount of sulfur and sulfurization temperature. The optimized FeS2/S,N co‐doped carbon NFs/Ecoflex NFE not only exerted an excellent impedance matching characteristic, but also displays boosted conductive loss and polarization loss capacities. Amongst, the designed NFE achieved an ultra‐wide effective absorption bandwidth (EAB) of 7.40 GHz and minimum reflection loss (RLmin) of −21.82 dB at the thin matching thickness (≈2.00 mm). Furthermore, FeS2/S,N co‐doped carbon NFs/Ecoflex NFE simultaneously presents greatly improved mechanical property, thermal insulation, hydrophobicity, and corrosion resistance. Through designing metastructures, the NFE with a periodically closed‐ring resonant structure realized an EAB of 32.64 GHz (ranging from 7.36 to 40.00 GHz). Overall, this research contributes valuable insights for the design of next‐generation EMWAMs with satisfactory multifunctionalities, demonstrating their significant potential for application in smart devices and challenging environments. [ABSTRACT FROM AUTHOR]

Highlights Hot compression molding was used to produce biocomposites from ramie plain‐woven fabric‐reinforced polylactic acid (PLA). Prior to composite fabrication, alkali and dipodal silane (bis(3‐trimethoxysilylpropyl) amine) (BAS) were applied to improve fiber‐matrix adhesion. Mechanical tests revealed improvements in tensile and flexural strength due to interfacial adhesion. The flexural strength of ramie PLA composite samples treated only with silane (SR‐PLA) was the highest, at 136.35 MPa. Young's modulus was 7.51 GPa. BAS treatment was crucial for ensuring strong adhesion between the fabric and the PLA matrix. In combined alkali‐BAS‐treated composites (ASR‐PLA), the glass transition and crystallization temperatures disappeared completely, affecting PLA morphology. The maximum heat of absorption (373°C) was found in SR‐PLA composites, suggesting electrostatic interactions created a three‐dimensional network. In conclusion, the initial incorporation of dipodal silane resulted in the formation of six silanol linkages with ramie fabric, leading to enhancements in the mechanical and thermal characteristics of ramie–PLA composites. Alkali and BAS treated Fabrics ironed to remove treatment‐induced wrinkles. Carded PLA fiber with consistent density and weighted in four equal portions. Fabric and PLA lay alternatively in warp direction before compression molding. SR‐PLA composites exhibited improved thermal and mechanical properties. [ABSTRACT FROM AUTHOR]

Highlights Boron nitride (BN) has excellent thermal conductivity (TC), however, it exhibits high surface energy, strong chemical inertness, poor interface compatibility with polymer matrices, and difficulty in even dispersion within‐polymer matrix, preventive effective construction of TC pathways. Four kinds of modified boron nitride/polyurethane composites (BTPUC) were prepared by different silane‐functionalized BN with polyurethane (TPU). Among them, 3‐trimethoxysilylpropylmethacrylate (TMSPMA)‐functionalized BN demonstrated better interface compatibility with TPU, significantly improving the mechanical properties and TC of the composites compared to the other three functionalized BN addition. The BN@TMSPMA/PU exhibited good TC and mechanical properties, with a TC of 0.865 W/mK, a tensile stress and a tensile strain of 9.65 ± 1.40 MPa and 759.88 ± 67.93%, respectively. It also showed good electrical insulation properties and mechanical durability. Therefore, the as‐prepared BN@TMSPMA/PU have broad prospects as flexible thermal‐management materials. The composites are constructed by TMSPMA‐modified BN and polyurethane by NIPS. The composites show good mechanical properties and cyclic failure resistance. The composites exhibit good thermal conductivity and electrical insulation. [ABSTRACT FROM AUTHOR]

The growing environmental pollution issues by synthetic textile products demand sustainable natural textile alternatives. This paper aimed at extracting and characterizing a new fiber called Ficus thonningii fiber from Ficus thonningii trees found in Ethiopia to be used as a source of textile fiber for different applications. The study utilized water and chemical extraction with sodium hydroxide methods. Physical, mechanical, and chemical properties such as length, diameter, fineness, tenacity, moisture content, moisture regain, cellulose, hemicellulose, lignin, and ash content were characterized. The results revealed that Ficus thonningii fiber possesses comparable characteristics with jute, sisal, and flax fibers that can be used for different applications. The fiber exhibits tenacity of 39.65 cN, an elongation of 2.60%, a moisture content of 10.78%, and a moisture regain of 11.98% when extracted chemically. While it exhibits a tenacity of 37.83 cN, an elongation of 3.02%, a moisture content of 10.35%, and a moisture regain of 11.02% when extracted using water extraction method. Both extraction methods yield a fiber length of 101.50 mm. The chemical composition of the fiber obtained through water extraction consists of 52.35% cellulose, 19.20% hemicellulose, 17.20% lignin, and 1.20% ash. On the other hand, the chemical extraction method results in a composition of 63.57% cellulose, 16.10% hemicellulose, 12.10% lignin, and 0.83% ash. These results confirm the potential use of Ficus thonningii tree as a valuable source of coarse fibers for various technical textile applications. [ABSTRACT FROM AUTHOR]

Bagworm silk proteins, which contain crystalline structures with large β‐nanocrystal sizes, are ideal candidates for biosynthetic high‐performance fibers. However, the extremely high glycine content and greater molecular weight limit their heterologous expression efficiency and further application exploration. Here, a multi‐module assembly strategy is developed to engineer novel chimeric structural proteins by incorporating the mechanical functional domains of bagworm silk proteins with the C‐terminal self‐assembly domains of spider silk proteins. By selecting a single repetitive unit of the functional region of bagworm silk proteins, the challenge of low heterologous expression efficiency is successfully addressed. Furthermore, the content and ordering of β‐sheet structure are enhanced in the chimeric proteins through the alignment mediated by the spider silk C‐terminal domain and ligation facilitated by split inteins, resulting in a remarkable Young's modulus of ≈15 GPa. This surpasses many artificial protein fibers, synthetic polymer fibers, and even natural spider silk. Notably, these protein fibers are drawn into surgical sutures and demonstrate superior wound healing effects compared to clinical suture in a skin wound model. This research presents a novel strategy for developing high‐performance protein fibers, which will expand the scope of their mechanically demanding applications. [ABSTRACT FROM AUTHOR]

Carbon fiber (CF) is one of ideal reinforcements to hydroxyapatite (HA) owing to its unique structure, excellent biocompatibility and high mechanical properties. However, the mechanical property of CF reinforced HA (CF/HA) composites cannot be effectively improved due to the mismatch in surface properties and thermal expansion coefficients between CF and HA. In order to solve the problems, nano-hydroxyapatite (nHA) coating with different thickness was fabricated on the CF surface. The effect of the coating thickness on mechanical property of nHA-coated CF/HA composites was studied by finite element analysis. The CF with proper nHA coating thickness was subsequently used to reinforce HA. The compressive strength of nHA-coated CF/HA composites was approximately 97.3 % and 164.6 % higher than those of the uncoated CF/HA composites and pure HA ceramics, respectively. The interface properties and crack propagation were analyzed by cohesive element in the finite element analysis. The toughening mechanism of the composites included interfacial debonding, crack deflection, crack branching, and crack bridging. The mechanical properties of nHA-coated CF/HA composites were enhanced due to the strong interfacial bonding strength and reducing cracking in HA matrix. The prepared nHA-coated CF/HA composites satisfy the requirement of the mechanical properties of human load-bearing bone. It can be used to prepare cages, plates, screws, pins and other compact bone substitute parts in bone grafting. The study provided a method for construction of nHA-coated CF/HA composites with the designed properties by adjusting the nHA coating on the fiber and can be used to design other fibers reinforced ceramic matrix composites. [Display omitted] [ABSTRACT FROM AUTHOR]

A coral-like network carbon aerogel was synthesized by introducing acid-modified carbon nanofibers (a-CNF) into phenolic (PR) aerogel through chemical grafting, followed by high-temperature carbonization. The bonding interaction between a-CNF and PR was analyzed by FT-IR spectroscopy. The microstructure of a-CNF/PR composite aerogel (a-CNF/PRA) was studied by SEM and pore structure analysis. The results showed that introducing 5 wt% of a-CNF was most favorable for forming a porous network of a-CNF/PRA. SEM photographs and pore structure analysis indicated that a-CNF/C composite aerogel (a-CNF/CA) developed a stable porous skeletal structure during carbonization. TEM images revealed that the complete porous skeleton consisted of a-CNF encapsulated by carbon layers. The carbonization shrinkage of a-CNF/CA was only 26.53% due to the presence of a-CNF as the skeleton support. Compared to carbon aerogel, a-CNF/CA exhibited lower density (0.072 g cm−3), thermal conductivity (0.0452 W m−1 K−1), and higher compressive strength (up to 3.26 MPa) up to 3.26 MPa than that of carbon aerogel (1.21 MPa). These findings confirmed the excellent mechanical and thermal insulation properties of a-CNF/CA. [ABSTRACT FROM AUTHOR]

As an important turbocharging equipment, hydraulic pumps are prone to internal wear and corrosion problems. In order to improve its friction and wear performance, a ceramic coating strengthening scheme based on laser cladding technology was proposed. The roughness, thickness, width, hardness, and residual stress of the coating under different laser powers and scanning rates were measured, and the effect of process parameters on the coating structure was determined to ensure the optimal basic mechanical properties of the coating. Under the experimental conditions of 10–30 N pressure and 10–20 mm/s lubricated friction velocity, high cycle tribological tests were conducted, and the changes in average friction coefficient, wear amount, and surface wear mechanism were compared and analyzed. To verify the impact of reinforced coatings on corrosive environments, friction and wear tests were conducted in hydraulic oil environment with a pH of 6.4 and particle impurity content of approximately 5 %. Through electron microscopy, the friction morphology was observed and the wear mechanism was analyzed. In order to study the effects of different overloads (including temperature and pressure loads) on friction damage, overload friction damage analysis was conducted under low cycle fatigue loading conditions. The Rtec friction machine was applied, and the test temperature and pressure were set at 400 °C, 500 °C, 750 MPa, and 1000 MPa, respectively. The coating sample speed was set to 500 r/min and the slip rate is set to 5 %. Each sample was worn for 4 cycles under different pressures, with each cycle worn for 1 hour, then the surface roughness morphology and micro wear morphology were obtained. The research results indicate that the friction stability, wear resistance, and hardness of the coating have significantly improved, and it has stronger adaptability to hard or sharp materials, making it very suitable for the working environment of hydraulic pumps. [ABSTRACT FROM AUTHOR]

Waste concrete is a large amount of solid waste produced in the process of urban construction and renewal in China. Its resource utilization is of great significance for saving mineral resources and improving urban environmental quality. The present study was designed to investigate the effects of mechanical grinding time on the particle size distribution and activity of recycled waste concrete powder (RWCP). Combined with unconfined compressive strength, slump, electric flux and chloride ion penetration resistance tests, the effects of RWCP on the mechanical properties, working performance and impermeability of concrete were analyzed, and the phase and microstructure of concrete containing RWCP were analyzed by XRD and SEM. The results showed that the RWCP is mainly composed of quartz, gismondine, C2S, cancrinite and portlandite. The optimum activity of RWCP obtained by ball milling for 45 min was 44.41%. RWCP can improve the fluidity of concrete and shorten the initial setting time of concrete. When the blast furnace slag in the concrete was replaced by the RWCP, the early strength and impermeability of the concrete decreased. When RWCP replaced blast furnace slag by 69.1%, the UCS of the concrete at 1, 3, 7, and 14 d decreased from 9.56, 22.1, 34.1, and 41.2 MPa to 5.9, 14.5, 22.7, and 33.2 MPa, respectively. While RWCP replaced fly ash, the normal strength of concrete increased with the increase in fly ash replacement amount. When RWCP completely replaced FA in concrete, the 28-day strength of the concrete increased from 45.2 MPa to 50.8 MPa. The impermeability results showed that the appropriate substitution of RWCP for fly ash was beneficial to increase the impermeability of concrete while excessive substitution reduced. Based on these results, the RWCP has the potential for large-scale application in the preparation of concrete. [ABSTRACT FROM AUTHOR]

Directed energy deposition with laser beam (DED-LB) components experience significant residual stress due to rapid heating and cooling cycles. Excessive residual tensile stress can lead to cracking in the deposited sample, resulting in service failure. This study utilized digital image correlation (DIC) and thermal imaging to observe the in situ temporal evolution of strain and temperature gradients across all layers of a deposited 316 L stainless steel thin wall during DED-LB. Both continuous-wave (CW) and pulsed-wave (PW) laser modes were employed. Additionally, the characteristics of thermal cracks and geometric dislocation density were examined. The results reveal that PW mode generates a lower temperature gradient, which in turn reduces thermal strain. In CW mode, the temperature–stress relationship curve of the additive manufacturing sample enters the "brittleness temperature zone", leading to the formation of numerous hot cracks. In contrast, PW mode samples are almost free of cracks, as the metal avoids crack-sensitive regions during solidification, thereby minimizing hot crack formation. Overall, these factors collectively contribute to reduced residual stress and improved mechanical properties through the adjustment of pulsed-wave laser deposition. [ABSTRACT FROM AUTHOR]

Additive friction stir deposition (AFSD) is a novel solid-state additive manufacturing method developed on the principle of stirring friction. Benefits from its solid-phase properties, compared with traditional additive manufacturing based on melting–solidification cycles, AFSD solves the problems of porosity, cracks, and residual stress caused by the melting–solidification process, and has a significant improvement in efficiency. In AFSD, the interaction between feedstocks and high-speed rotating print heads suffers severe plastic deformation at high temperatures below the melting point, ending up in fine, equiaxed recrystallized grains. The above characteristics make components by AFSD show similar mechanical behaviors to the forged ones. This article reviews the development of AFSD technology, elaborates on the basic principles, compares the macroscopic formability and material flow behavior of AFSD processes using different types of feedstocks, summarizes the microstructure and mechanical properties obtained from the AFSD of alloys with different compositions, and finally provides an outlook on the development trends, opportunities, and challenges to the researchers and industrial fields concerning AFSD. [ABSTRACT FROM AUTHOR]

Diseases and traumatic injuries to the central nervous system (CNS) demand the development of new biomaterials to improve healing and treatment options. Matching material mechanical properties to specific tissues and optimizing material porous structures are central goals for improving biomaterials. However, biomaterials with both precision-controlled porous structures and brain-matched mechanical properties (low modulus) are still lacking. In this study, we developed soft hydrogel scaffolds with mechanical properties similar to that of CNS tissues, and a uniform 40 µm porous structure—40 µm pores have been shown to be optimal for healing in many tissues. The two characteristics were achieved by a new fabrication process combining phase separation and sphere templating. The resulting scaffolds are non-cytotoxic according to the ISO 10993-5 standard. In addition, the three-dimensional culture of microglial cells within the scaffolds demonstrates cell attachment and maintenance of a rounded, quiescent morphology, potentially due to spatial confinement. These results justify further in vivo studies and suggest broad potential in CNS applications, such as brain-computer interfaces, neural regeneration, and basic neurobiology. Subject classification codes: Neural Interfaces, soft hydrogel, synthetic biomaterials [ABSTRACT FROM AUTHOR]

In the ultrasonic testing of the mechanical properties of ferromagnetic materials, the main excitation mechanism modes of ultrasonic waves are Lorentz force mechanism ultrasonic and magnetostriction mechanism ultrasonic. Lorentz force mechanism ultrasonic mainly detects the conductive characteristics of materials, while magnetostriction mechanism ultrasonic mainly detects the hysteresis characteristics of materials. However, conventional electromagnetic acoustic transducers (EMATs) cannot simultaneously characterise these two characteristics of ferromagnetic materials. In this study, we conclude from the finite element simulation that a quantitative lift-off distance (i.e. the distance between EMAT and the specimen) can change the main mechanism mode of the excited ultrasonic wave. Based on this conclusion, an electromagnet electromagnetic acoustic transducer with dual main excitation modes (DM-E-EMAT) is designed, which can realise the dual mode switching of the main Lorentz force mechanism and main magnetostriction mechanism by adding or removing hollow square gasket. The ultrasonic testing of ferromagnetic materials based on the two main mechanisms of DM-E-EMAT can simultaneously characterise the conductivity and magnetostriction properties of ferromagnetic materials, which enables the characterisations of two types of characteristic parameters with one transducer, improves the efficiency of electromagnetic ultrasonic non-destructive testing of the mechanical properties and reduces the detection errors of ferromagnetic material. [ABSTRACT FROM AUTHOR]

Microcapsules encapsulating payloads are one of the most promising delivery methods. The mechanical properties of microcapsules often determine their application scenarios. For example, microcapsules with low mechanical strength are more widely used in biomedical applications due to their superior biocompatibility, softness, and deformability. In contrast, microcapsules with high mechanical strength are often mixed into the matrix to enhance the material. Therefore, characterizing and regulating the mechanical properties of microcapsules is essential for their design optimization. This paper first outlines four methods for the mechanical characterization of microcapsules: nanoindentation technology, parallel plate compression technology, microcapillary technology, and deformation in flow. Subsequently, the mechanisms of regulating the mechanical properties of microcapsules and the progress of applying microcapsules with different degrees of softness and hardness in food, textile, and pharmaceutical formulations are discussed. These regulation mechanisms primarily include altering size and morphology, introducing sacrificial bonds, and construction of hybrid shells. Finally, we envision the future applications and research directions for microcapsules with tunable mechanical properties. [Display omitted] • Characterization methods of the mechanical properties of microcapsules are delineated. • Regulatory mechanisms of the mechanical properties of microcapsules are summarized. • The applications and future research directions of microcapsules with controllable mechanical properties are discussed. [ABSTRACT FROM AUTHOR]

Al2O3‐based composite seal with 10 wt% Al powder addition (A10) possesses excellent plastic and mechanical performance under wide temperature range of solid oxide fuel cell. The thickening phenomenon of A10 seal between 250°C–400°C and 600°C–750°C is caused by the thermal expansion of organic additives and the volume expansion when solid–liquid Al react with oxygen to form Al2O3. The thickness change rate reaches the maximum which is about 5% at 300°C and is about 4.46% at 650°C. The Gibbs free energy for reaction between Al and Al2O3 in the temperature range of 523–1 023 K is all less than 0, which is proved by the fact that A10 exhibits excellent self‐expansion and thermodynamic properties in the solid oxide fuel cell operating temperature. [ABSTRACT FROM AUTHOR]

A novel CaO–Al 2 O 3 –SiO 2 –Li 2 O (CASL) glass was developed for bonding yttria–stabilized zirconia ceramics (YSZ). The CASL glass possessed a coefficient of thermal expansion (CTE) that matched with YSZ and exhibited outstanding wettability on the surface of YSZ substrate. During the bonding process, mutual dissolution and diffusion between YSZ and CASL glass took place, which ensured good interface bonding. Furthermore, the rapid cooling speed led to a completely amorphous seam, which allowed the CTE of the seam to correspond with that of the original glass. The optimal flexural strength of YSZ/YSZ joints could reach more than 90 % of that of the YSZ. [ABSTRACT FROM AUTHOR]

Polymer-derived SiBCN ceramic aerogels have attracted extensive attention in recent years due to the excellent electromagnetic wave absorption and thermal insulation properties. With these merits, SiBCN aerogels are promising for the application of high-speed vehicles requiring thermal and electromagnetic shielding. However, the brittleness and poor mechanical property of SiBCN aerogel seriously hinder its practical applications. In this paper, SiBCN/SiBCN nf composite ceramic aerogels with enhanced mechanical property were prepared by combining electrospinning technique with simultaneous pyrolysis process of polyborosilane (PBS) fibers and precursor aerogels. The effect of varying fiber content on the density, mechanical property, thermal insulation as well as microwave absorption performance of the composite aerogel was investigated. In addition, the underlying toughness mechanism of the SiBCN/SiBCN nf composite ceramic aerogel was elucidated. The compressive strength of the SiBCN/SiBCN nf composite aerogel increased from 0.29 MPa to 1.62 MPa. Importantly, while the mechanical strength of the composite aerogel increased by about 5.5 times, SiBCN/SiBCN nf aerogel still exhibits low density of 0.105 g/cm³, low thermal conductivity of 0.048 W/mK and a minimum reflection loss (RL min) of −20 dB. Owing to the integration of electromagnetic wave (EMW) absorption and thermal insulation properties, SiBCN/SiBCN nf aerogels pave the way for the construction of thermal and electromagnetic shielding material for high-speed vehicles. [ABSTRACT FROM AUTHOR]

An enhanced Ni50A composite coating was formed on the AISI 1045 steel surface using Ti, B 4 C, and Ni50A powders. The work meticulously examined the effects of various process parameters, including laser power (800, 1200, and 1600 W) and scanning speed (4, 6, and 8 mm/s), as well as different Ti/B 4 C powder ratios (2:1, 3:1, and 4:1, mol.%) on the defect, hardness, wear resistance, and corrosion resistance of the coating. The microstructure of the coating showed that TiB 2 and TiC synthesized in situ were the key phases for coating enhancement, and there were a variety of solid solutions (FeNi 3 and Cr 2 Ni 3). TiB 2 particles showed dark gray hexagons and long rectangular blocks. The TiC particles mainly appeared in light gray dendritic shapes, occasionally petal-shaped and equiaxial forms, and grew around TiB 2. The research results showed that increased laser power and the Ti/B 4 C ratio decreased coating hardness and wear resistance. When the scanning speed increased, the hardness and wear resistance of the coating were significantly improved. The main wear mechanisms of the TiB 2 –TiC ceramic phase coating were oxidative wear and abrasive particle wear. Besides, the higher laser power and Ti/B 4 C ratio reduced the defect rate of the coating and enhanced the corrosion resistance. However, as the scanning speed increased, the defect rate increased, which decreased the corrosion resistance of the coating. The comprehensive performance evaluation showed that under the conditions of the laser power of 1200 W, a scanning speed of 8 mm/s, and a Ti/B 4 C ratio of 4:1, the coating exhibited optimal performance (dilution rate = 10.928 ± 0.090 %, defect rate = 8.657 ± 0.128 %, hardness = 63.300 ± 1.159 HRC, wear volume = 0.0149 ± 0.000100 mm3, Ecorr = − 0.565 ± 0.001 V, Icorr = 1.058 E − 06 ± 1.528 E − 09 A ⋅ c m 2). The results provide an important basis for research on the high-quality and efficient strengthening technology and performance of refractory alloys. [ABSTRACT FROM AUTHOR]

The scotch yoke inerter (SYI) is a new geometrically nonlinear vibration isolator with a smaller maximum transmissibility than linear inerter systems. The influence of internal friction and the damping effect on the response of the SYI system for seismic isolation can be significant and needs to be studied. In this study, a small-scale SYI is designed and tested, and an accurate model of SYI is developed for describing its dynamic behavior. Then, the motion equation of the coupled structure-SYI system is established, and several dynamic analyses are studied, including the amplitude-frequency response, the critical excitation amplitude, the backbone curve, the peak response, the starting frequency, and the linearization design, and many fitting expressions for engineering applications are proposed. Finally, the vibration isolation performance of SYI is investigated when friction and damping effects are considered or not, using a single-degree-of-freedom system and a building structure as examples. For harmonic excitations, the maximum transmissibility of the SYI system is superior to that of the linear inerter system, and its advantage becomes more obvious as the excitation amplitude increases. Its seismic isolation effect is slightly better than that of a linear inerter for seismic excitations, where the SYI considering friction and damping effects is better. Practical Applications: A scotch yoke inerter is a geometrically nonlinear inerter that is simple to construct, easy to implement, and has the advantage of variable inertance. The variation of inertance is reflected in two aspects: first, its nominal inertance can be changed by adjusting the location of the pin; second, its dynamic inertance is related to its deformation, which can provide greater negative stiffness effects for larger external excitations. The precise and simplified output force model of the scotch yoke inerter is provided, which can be applied to the calculation and verification of the output force in the design of scotch yoke inerters. Fitting expressions for the critical excitation amplitude, starting frequency, and linearization design are proposed, which can provide a theoretical basis for the application of scotch yoke inerters in base-isolated structures. Compared with traditional linear inerters, scotch yoke inerters have a better isolation control effect, and this control effect can be further improved by making reasonable use of the internal friction and the damping in SYI. [ABSTRACT FROM AUTHOR]

Expanded polystyrene (EPS) concrete is a new typical composite concrete, but its material toughness and hydrophilicity are poor, leading to low strength and poor toughness. To solve this critical issue, this study used an interactive method of experimentation and simulation to systematically study the mechanism of how the synergistic strengthening of styrene–butadiene latex (SBL) and polyvinyl alcohol (PVA) fibers improves the performance of EPS concrete from the macro, micro, and nano multiscale systems. Macromechanical tests showed that the mechanical properties of EPS concrete are obviously improved by adding PVA and SBL. PVA fiber can reduce the compressive strength of EPS concrete but increase the flexural strength. The addition of SBL has a positive effect on the anticompression and flexural properties. Observation and analysis of microexperiments using electron microscopy, X-ray diffraction, and infrared spectroscopy showed that the addition of SBL improved the weak interface zone, increased the hydration crystallinity of unhydrated cement products, and formed a more abundant cement-based gel to fill weak cement pores, resulting in a more uniform and stable internal structure. At nano scale, the molecular dynamics interface models of EPS/calcium silicate hydrate (C-S-H), EPS/SBL/C-S-H, PVA/C-S-H, and PVA/SBL/C-S-H were established and simulated and analyzed at the nanoscale. The results showed that the addition of SBL played a crucial role in connecting organic polymers with inorganic silicates in a "bridge" form. It formed numerous hydrogen bonds and ionic bonds with EPS, PVA molecular chains, and C-S-H, effectively stabilizing the crystalline layer structure of hydrated calcium silicate and compensating for the weak hydrophilicity of EPS particles, making the EPS/C-S-H and PVA/C-S-H systems more tightly stable. Practical Applications: Expanded polystyrene (EPS) foam concrete, with its advantages of ultralightweight, easy construction, and environmental friendliness, has been widely used in the construction industry. It finds applications in load-bearing precast concrete components, thermal insulation boards, cushioning or structural insulation boards, composite floors, pavement substrates, building envelope structures, and offshore floating structures, among others. These structures possess high strength, excellent insulation performance, high fire resistance, good water repellency, affordability, and strong sound absorption and noise reduction capabilities. However, the hydrophobic nature and porosity of EPS material result in uneven stratification and segregation during the preparation of EPS particles, as well as the existence of numerous weak interface transition zones between EPS and cement-based materials. In order to further expand its prospects in engineering applications and meet the requirements of modern engineering, it is necessary to enhance the workability and mechanical performance of EPS concrete. This study combines experiments and simulations to investigate the mechanisms and methods for reinforcing EPS concrete from a multiscale and multiangle perspective, providing references for the preparation of more stable and high-performance EPS concrete. [ABSTRACT FROM AUTHOR]

Quasi-static compression/tension, dynamic compression/shear mechanical property tests, fracture morphology characterization, dynamic response experiment, numerical simulation, and calculation of the ultimate penetration velocity of the high-strength steel under the impact of large mass low-velocity fragments and small mass high-velocity fragments were carried out to study the ballistic performance of high-strength steel used for armor vehicle protection and clarify its dynamic response under Ballistic impact. The fracture mode of the high-strength steel under dynamic impact compression and shear was shear failure. A large number of fine parabolic shear dimples were formed on the fracture surface. The high-strength steel had an obvious strain rate strengthening effect and adiabatic shear sensitivity. The plug formed under the low-velocity impact of a large mass fragment was a cone shape, and the impact area of the target plate underwent slight bending plastic deformation. The damage of the fragment to the target plate includes both adiabatic shear failure and ordinary shear failure. Under the high-velocity impact of small mass fragments, the fragments were seriously deformed and destroyed, and the damage model of the target plate is adiabatic shear failure. [ABSTRACT FROM AUTHOR]

Iron–selenium (Fe–Se) alloys have potential as attractive biodegradable bone–implant materials, given the antitumor properties of Se in cancer prevention and therapy. However, the fabrication of Fe–Se alloys is challenging due to the volatility of elemental Se and the significantly different melting points of Se and Fe. In this study, we successfully fabricated Fe–xSe (x = 0.2, 0.4, 0.6, 0.8, and 1 wt.%) alloys using suction casting, with FeSe compounds as the Se source. The microstructures, tensile properties, corrosion behavior, biocompatibility, antibacterial ability, and antitumor properties of the Fe–Se alloys were evaluated. The microstructures of the Fe–Se alloys were composed of α–Fe and FeSe phases. Among the Fe–Se alloys, Fe–0.6Se showed the best combination of tensile properties, with a yield strength of 1096.5 ± 7.2 MPa, an ultimate tensile strength of 1271.6 ± 6.3 MPa, and a fracture strain of 15.6 ± 3.3 %, and a degradation rate of 56.9 ± 0.4 μm/year. Moreover, the Fe–0.6Se alloy showed superb antibacterial ability against S. aureus , antitumor activity against 143B osteosarcoma cells, and osteogenicity and biocompatibility toward pre–osteoblast MC3T3–E1 cells. In summary, adding 0.2–1.0 wt.% Se to Fe does not affect the growth of healthy cells but effectively inhibits the growth and reproduction of tumor cells, and the Fe–0.6Se alloy is promising for orthopedic applications owing to its unique combination of mechanical and biofunctional properties. This work reports on Fe-xSe (x = 0.2, 0.4, 0.6, 0.8, and 1 wt.%) alloys fabricated using suction casting. The microstructures of the Fe–Se alloys were composed of α-Fe and FeSe phases. Among the Fe–Se alloys, the Fe-0.6Se showed the best combination of tensile properties, with a yield strength of 1058.6 ± 3.9 MPa, an ultimate tensile strength of 1134.1 ± 2.9 MPa, and a fracture strain of 16.8 ± 1.5 %, and a degradation rate of 56.9 ± 0.4 μm/year. Moreover, the Fe-0.6Se alloy showed superb antibacterial ability against S. aureus , antitumor activity against 143B osteosarcoma cells, and significant osteogenic ability and biocompatibility toward pre-osteoblast MC3T3-E1 cells. In summary, the Fe-0.6Se alloy is promising for orthopedic applications owing to its unique combination of mechanical and biofunctional properties. [Display omitted] [ABSTRACT FROM AUTHOR]

High temperature and high strain rate rolling of Mg-1.0 wt.% Al alloy at 20, 50, and 80% rolling reduction were used to investigate the effect of rolling reduction on the microstructure, mechanical, and damping properties of Mg-1.0 wt.% Al alloy. The average grain size of Mg-1.0 wt.% Al sheet gradually decreases, and the DRX volume fraction, dislocation density, and texture strength gradually increase with the increase of rolling reduction. At 80% rolling reduction, the average grain size is 8.8 μm, and the ultimate tensile strength, tensile yield strength, and elongation of Mg-1.0 wt.% Al sheet gradually increase. The finest room temperature damping properties are shown by plates with a 50% reduction in mean dislocation density and grain size, where the damping value Q−1 for ε0.1 is 0.060. The damping properties in the damping capacity versus temperature curves grow with increasing reduction at a certain frequency. When the rolling reduction is certain, the damping performance decreases as the frequency increases. [ABSTRACT FROM AUTHOR]

The effect of sample‐build orientation on the tensile properties and deformation behavior of Ti6Al4V fabricated by laser powder bed fusion (LPBF) has been investigated by examining the changes in X‐ray diffraction spectra, microstructure, and dimension on the longitudinal cross‐sections after fracture. The anisotropy in strength is dominated by the difference in martensite (α′) lattice distortion, and the highest strength is achieved in the diagonally built sample (Z45) due to its largest α′ lattice distortion. The plastic deformation is mainly accommodated by sliding and micro‐void formation between α′ laths due to the insufficient number of slip systems in hexagonal close‐packed α′ phase. Therefore, the spatial orientation of α′ laths with respect to the loading direction is critical to the ductility. Different deformation mechanisms have been observed in different prior‐β grains due to their different α′ crystallographic orientations. The highest elongation is achieved in the vertically built sample (Z) because α′ laths in the vertically built sample are spatially at ±45° with the loading axis. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology 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.)

Fiber-reinforced composites were widely used in aerospace, automotive, and wind energy industries, due to their lightweight, high specific strength and stiffness, design flexibility, and durability. This study prepared hybrid fiber preforms using a three-dimensional braided technique. These preforms made of carbon fiber (CF) and aramid fiber (AF) were reinforced into resin-based (ER) composites by a vacuum infusion process (VIP). Our study focused on evaluating the mechanical properties of these composites under different blend arrangements and ratios, with four blend arrangements including layer-by-layer, half-by-half, bundle-by-bundle, and block-by-block. The results showed that the bending strain of the composites with a 3:1 aramid fiber/carbon fiber yarn ratio (3AF1CF) increased by 105.56% compared to that of CF/ER, and the addition of AF improved the toughness of the composite. The tensile strength and modulus of the composites with a 3:1 carbon fiber/aramid fiber yarn ratio (1AF3CF) were improved by 31.17% and 109.68%, respectively, compared to those of AF/ER, and the bending strength and modulus increased by 106.12% and 115.32%, respectively, and increasing the CF ratio thus significantly improved the mechanical properties of the composites. In addition, in four hybrid arrangements with the same AF/CF ratio, the aramid fiber/carbon fiber yarn ratio of 2:2 (2AF2CF-4) possessed the best mechanical properties, with tensile strength and of 608.36 MPa and 13.8 GPa, and bending strength and modulus of 417.203 MPa and 22.9 GPa, respectively. [ABSTRACT FROM AUTHOR]

Porous nickel-titanium (NiTi) manufactured using metal injection molding (MIM) has emerged as an innovative generation of drug-loaded stent materials. However, an increase in NiTi porosity may compromise its mechanical properties and cytocompatibility. This study aims to explore the potential of porous NiTi as a vascular drug delivery material and evaluate the impact of porosity on its drug loading and release, mechanical properties, and cytocompatibility. MIM, combined with the powder space-holder method, was used to fabricate porous NiTi alloys with three porosity levels. The mechanical properties of porous NiTi were assessed, as well as the surface cell growth capability. Furthermore, by loading rapamycin nanoparticles onto the surface and within the pores of porous NiTi, we evaluated the in vitro drug release behavior, inhibitory effect on cell proliferation, and inhibition of neointimal hyperplasia in vivo. The results demonstrated that an increase in porosity led to a decrease in the mechanical properties of porous NiTi, including hardness, tensile strength, and elastic modulus, and a decrease in the surface cell growth capability, affecting both cell proliferation and morphology. Concurrently, the loading capacity and release duration of rapamycin were extended with increasing porosity, resulting in enhanced inhibitory effects on cell proliferation in vitro and inhibition of neointimal hyperplasia in vivo. In conclusion, porous NiTi holds promise as a desirable vascular drug delivery material, but a balanced consideration of the influence of porosity on both mechanical properties and cytocompatibility is necessary to achieve an optimal balance among drug-loading and release performance, mechanical properties, and cytocompatibility. [ABSTRACT FROM AUTHOR]

Red clay exhibits characteristics such as softening owing to water absorption and cracking because of water loss, which can lead to slope instability, road cracking, and compromised structural integrity when used directly in roadbed filling. Although the addition of industrial materials such as cement is a common engineering treatment, it severely impairs soil renewability. Lignosulfonate (LS) extracted from paper plant waste fluids is a natural bio-based polymer with promising applications as a soil improver. In this study, the boundary moisture content and mechanical properties of LS-treated red clay were investigated using Atterberg, unconfined compressive strength, and direct shear strength tests. Additionally, the LS-treated red clay modification mechanism was explored at multiple scales using zeta potential analysis, X-ray diffraction, scanning electron microscopy coupled with energy dispersive spectroscopy, and Fourier transform infrared spectroscopy. The results indicated that the LS dosage significantly affected both the water content and mechanical strength of the red clay boundaries. The optimal dosage of LS for red clay was 3 wt. %, at which the liquid limit was reduced by 32.97%, the plastic limit by 19.33%, and the plasticity index by 48.37%. The 28-day compressive strength of LS-treated red clay was increased by 378.4%, and the direct shear strength was increased by 136%. Analysis of the microstructure and mineral composition revealed that the LS-treated red clay did not form new minerals, but primarily filled pores and connected soil particles. Through the combined effects of hydrogen bonds, electrostatic interactions, and cation exchange, the LS-treated red clay reduced the size of the mineral particles and the thickness of the mineral double electric layer, resulting in increased structural densification. These results are of great scientific significance for the ecological modification of soils. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of steel corrosion products in marine environment are key parameters for developing the concrete corrosion-induced model. In this study, steel corrosion products from steel plates, concrete specimens with 10 mm and 20 mm covers, and cracked beams in Zhejiang province were sampled and analyzed. Initially, the microstructure of the steel corrosion products were determined by X-ray diffractometry (XRD), thermogravimetric analysis (TG), scanning electron microscopy (SEM), and energy-dispersive spectrometry (EDS). Subsequently, the mechanical properties of steel corrosion products including nanoindentation elastic modulus, hardness and instantaneous elastic modulus were measured by nanoindentation and consolidation experiments. This study holds potential for establishing the concrete corrosion-induced model and assessment of the concrete structure durability in marine environment. [ABSTRACT FROM AUTHOR]

Lubricant‐infused organo‐gels with low surface energy solvents represent an environment‐friendly lubricating material, while the poor mechanical performance incapacitates them to harsh and intricate service conditions. To address this challenge, a simple yet highly effective strategy to prepare strong, smart, and slippery organo‐gels by glassifying the polymer network is reported. As a proof of concept, appropriate amounts of rigid solvophobic poly(phenyl methacrylate) (PPMA) units are integrated into a solvophilic poly(cyclohexyl acrylate) (PCHA) network infiltrated with lubricant. Upon forming bicontinuous phase‐separated structures, the rigid solvent‐free PPMA segments stay in glassy states, serving as a load‐bearing phase to toughen the materials effectively. Meanwhile, the soft PCHA phase maintains lubricity and extensibility by holding a substantial amount of lubricant. Owing to the synergistic effect, the gels manifest glass‐like mechanical performance with high rigidity (46.6 MPa), strength (7.7 MPa), and toughness (23.7 kJ m−2). Moreover, the materials exhibit high thermo‐sensitivity with the elastic modulus reversibly decreasing from 46.6 MPa at 20 °C to 0.23 MPa at 50 °C, endowing the gels with shape‐memory properties. Furthermore, the organo‐gels display satisfactory anti‐adhesiveness to various foreign matters. Taken together, the work represents a facile and universal strategy to reinforce organo‐gels, thereby adapting them to various applications. [ABSTRACT FROM AUTHOR]

Highlights With the rapid development of modern transportation systems, optimizing the relationship between structure and performance to obtain natural rubber‐based nanocomposites with excellent comprehensive performance is still worth to investigation. Herein, the regulation of flocculation potential through different flocculants selection on the thermomechanical properties for carbon black/graphene oxide reinforced natural rubber (CB/GO/NR) nanocomposites were investigated based on the compression electric double layer theory. The results showed that formic acid owned the highest zeta potential with comparison of sodium chloride (NaCl), calcium chloride (CaCl2), and aluminum chloride (AlCl3). Meanwhile, as the content was 8 wt%, tensile strength, tearing strength and thermal conductivity could achieve to 27.64 MPa, 56.89 N/mm, and 1.05 W m−1 K−1, respectively. While the heat generation after compression fatigue dropped to 10.1°C. These findings reveal that the highest zeta potential of formic acid could promote the improvement of flocculation degree between GO and NR latex and significantly enhanced the thermomechanical properties of CB/GO/NR nanocomposites due to the larger flocculation potential difference. Therefore, this study not only provides important theoretical insights for preparing high‐performance NR‐based nanocomposites, but also highlights the crucial role of high zeta potential flocculants in optimizing the composite performance. More importantly, the findings offer the creative insights for preparation of the excellent comprehensive NR nanocomposites for the practical industry application. The effect of flocculation degree on the properties of CB/GO/NR composites was studied. Formic acid was benefit to the flocculation and could promote the surface interaction. CB/GO/NR composites possessed the improved thermal and mechanical properties. [ABSTRACT FROM AUTHOR]

For the reaction-formed graphite/SiC composites, the presence of cracks and poor mechanical properties seriously affect their reliability as wear resistant or sealing materials. In this work, a porous carbon preform was pressure formed first by carbon-composite-powder (PFC@G) and carbon black, impregnated with resin and carbonized subsequently, which can heal the micro-cracks, increased the strength of porous carbon preforms and finally reduce the reactivity of liquid Si and carbon during the reaction forming process. The results show that the modified porous carbon preform has a 4.8 % reduction in porosity and a 3.98 times increase in compressive strength. After reactive melt infiltration, the prepared graphite/SiC composites had a compact and isotropic structure and obtained the highest carbon content of 66.18 vol%. In addition, the coupling effect of the PFC@G size on the carbon content and mechanical properties of composites was studied. With the decreasing of the PFC@G size, the mechanical properties of the composites increased and the carbon content decreased. The sample with a carbon content of 48 vol% and a bending strength of 137 MPa exhibited excellent self-lubrication properties. [ABSTRACT FROM AUTHOR]

Thermal shock resistance and mechanical reliability of aluminum nitride (AlN) ceramic substrates are essential in electronic device modules. In this study, the thermal shock behavior of AlN doped with aluminum - yttrium oxide (Al - Y 2 O 3) was explored. The results indicate that adding Al to AlN ceramics increases its flexural strength, thermal conductivity, and thermal expansion coefficient. The microcracks caused by thermal mismatch between the AlN matrix and the secondary phases relieved internal stress, thereby improving thermal shock resistance of AlN ceramics. Furthermore, the addition of Al isolates and homogenizes the secondary phases, resulting in a more uniform microstructure and strengthened grain boundaries, which enhance the flexural strength, Weibull modulus, and thermal shock resistance. After introducing 0.5 wt% Al, the Weibull modulus of AlN ceramics increased by 73.37 %, and their critical thermal shock temperature difference exceeded 800 °C, with a maximum residual strength of 488.01 ± 48.26 MPa at 600 °C. Overall, an appropriate amount of Al improves the reliability and thermal shock resistance of AlN ceramics. [ABSTRACT FROM AUTHOR]

Based on the advantages of triply periodic minimal surface (TPMS) porous structures, extensive research on NiTi shape memory alloy TPMS scaffolds has been conducted. However, the current reports about TPMS porous structures highly rely on the implicit equation, which limited the design flexibility. In this work, novel shell-based TPMS structures were designed and fabricated by laser powder bed fusion. The comparisons of manufacturability, mechanical properties, and shape recovery responses between traditional solid-based and novel shell-based TPMS structures were evaluated. Results indicated that the shell-based TPMS porous structures possessed larger Young's moduli and higher compressive strengths. Specifically, Diamond shell structure possessed the highest Young's moduli of 605.8±24.5 MPa, while Gyroid shell structure possessed the highest compressive strength of 43.90±3.32 MPa. In addition, because of the larger specific surface area, higher critical stress to induce martensite transformation, and lower austenite finish temperature, the Diamond shell porous structure exhibited much higher shape recovery performance (only 0.1% residual strain left at pre-strains of 6%) than other porous structures. These results substantially uncover the effects of structural topology on the mechanical properties and shape recovery responses of NiTi shape memory alloy scaffolds, and confirm the effectiveness of this novel structural design method. This research can provide guidance for the structural design application of NiTi porous scaffolds in bone implants. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS 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 China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS 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.)

Carbon fiber reinforced polyamide 66 (CF/PA66) sheets are ultrasonically welded by applying nylon meshes as energy directors (EDs) in this paper. The influence of mesh dimensions is revealed by observing the joint formation process, joint mechanical performance, joint cross‐sectional morphology and joint failure mode. Results show that the joint formation process can be divided into wire flattening stage, ED spread stage, tight bonding stage, and mixing stage. The nylon mesh ED with moderate wire spacing, small wire diameter and small mesh area promotes better weld quality. Welding energy will be dispersed rather than concentrated if the mesh area is too large, resulting in reduced failure load. The joints exhibit two fracture modes: interfacial fracture (IF) and workpiece fracture (WF), and the fracture mode of the joints with nylon mesh EDs transits from IF to WF as the welding energy increases. Highlights: Five types of nylon mesh are used as energy directors to join CF/PA66 sheets by ultrasonic welding.The influence of nylon mesh dimensions on the mechanical property and fracture mode of joints is investigated.The formation process of ultrasonically welded joints can be separated into wires flattening stage, ED spread stage, tight bonding stage, and mixing stage. [ABSTRACT FROM AUTHOR]

As is well known, Laser print paper is usually produced with high‐quality chemical wood pulp. The laser print waste paper fiber (LPWF) is a high‐quality secondary fiber, and the research and development of high‐value utilization technology for laser print waste paper has attracted much attention in the field of renewable resource recycling. In this study, LPWF was used to reinforce poly(lactic acid) (PLA) composites in the field, and the composites were modified with bioenzyme, cationic polyacrylamide (CPAM), and nano‐silicon carbide (Nano‐SiC) to enhance the interfacial compatibility of LPWF/PLA composites. The study systematically investigated the effects of various modification methods on the characteristics and degradability of composites made from laser print waste paper fiber reinforced PLA resin matrix. The results showed that the mechanical properties of the composites treated with CPAM and Nano‐SiC were significantly improved, with tensile strengths of 54.3 and 59.5 MPa, and flexural strengths of 85.1 and 91.5 MPa, respectively, and the water absorption of the composites was reduced after the modification treatment, while the thermal stability was improved. The degradation performance of the composites in various water environments indicated that the inclusion of LPWF accelerated the water degradation rate of the composites, with the maximum degradation rate of the composite reaching 1.26% in 30 days. Highlights: Laser print waste paper is an excellent quality recyclable fiber resource.Four modifiers were used to modify LPWF/PLA composites.Characteristics and degradability of the composites were investigated.Significantly improved properties of CPAM and Nano‐SiC modified composites.The degradation rate of composites is increased by the addition of LPWF. [ABSTRACT FROM AUTHOR]

Additive Manufacturing (AM) of carbon fiber reinforced polyetheretherketone (CF/PEEK) composites with excellent performance by Powder Bed Fusion (PBF) has great potential in the applications where high strength and high service temperature are required. However, the reinforcement mechanisms of CF/PEEK composites based on the PBF process are complex and show significant differences from traditional processing methods. In this paper, the mechanical properties of CF/PEEK prepared by PBF were investigated. The results showed that its X‐axis tensile strength and modulus were approximately equal to or a bit lower than the theoretical value with randomly distributed CF, but much lower than the theoretical value with unidirectional distribution of CF in composites. Meanwhile, mechanical strength anisotropy was observed. The composites' Y‐axis tensile strength was slightly lower than X‐axis, and the lowest strength existed in Z‐axis. To improve the weak Z‐axis strength, post‐processing of annealing and solvent‐induced crystallization were carried out, and the Z‐axis tensile strength of post‐processed parts reached 50 MPa, which was 62% higher than untreated samples. Consequently, suitable CF and proper post‐ processing for AM of high strength CF/PEEK were proposed, which would promote the industrial application of this technology. Highlights: The effect of CF on mechanical property of CF/PEEK prepared by PBF were studied.The optimal CF for PBF of high strength CF/PEEK were obtained.The post‐processing method for improving the Z‐axis strength were proposed.CF/PEEK with comprehensive mechanical property was successfully prepared by PBF. [ABSTRACT FROM AUTHOR]

Highlights Recently, thermosetting epoxy resin is expected to be substituted by thermoplastic featured from green circular economy. Poly(methyl methacrylate) (PMMA) has been well known as one promising thermoplastic resin, although its mechanical property needs to be further investigated. In this paper, the free radical polymerization of methyl methacrylate (MMA) was initiated by lauroyl peroxide/N,N‐dimethylaniline (LPO/DMA) and lauroyl peroxide/N,N‐dimethyl‐p‐toluidine (LPO/DMT) redox system at room temperature, respectively. The PMMA (n(MMA:LPO:DMA) = 200:1.2:1) exhibited excellent mechanical properties, and the tensile strength was 66.5 MPa, the bending strength was 118.0 MPa. The tensile strength increased to 78.9 MPa at −40°C, which suggested a promising application at low temperature. The resin was applied to fabricate continuous glass fiber reinforced PMMA (GF/PMMA) composites by vacuum‐assisted resin infusion. The 0° tensile strength and modulus were 1.17 and 43.7 GPa and 90° tensile strength and modulus were 48.3 MPa and 13.2 GPa, respectively. The mechanical properties of GF/PMMA composites are higher than GF/epoxy. Moreover, PMMA resin and glass fiber can be recycled from GF/PMMA composites by MMA as solvent, which is more energy‐efficient and environment‐friendly. This work is of great significance for preparing sustainable resin and composites. GF/PMMA composites were fabricated by vacuum perfusion. GF/PMMA composites showed higher mechanical properties than GF/epoxy. GF/PMMA composite was recycled with MMA and closed‐loop recovery was achieved. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, additive manufacturing (also known as 3D printing) has gradually become the mainstream method for producing titanium alloy brackets for removable partial dentures. Heat treatment, as an important method to improve the mechanical properties of 3D printed titanium alloys, has become a current hot topic of attention. OBJECTIVE: To summarize the main heat treatment technologies currently applied to 3D printed titanium alloy specimens (including annealing, solution aging, hot isostatic pressing, and other heat treatments) and their effects on the mechanical properties and microstructure of 3D printed titanium alloy specimens, providing a theoretical basis for improving the heat treatment technology of removable partial denture titanium alloy supports. METHODS: A computer search was conducted on research materials related to 3D printed titanium alloy heat treatment in databases such as CNKI, PubMed, and ScienceDirect. The search period was from 2012 to 2023. A total of 61 articles were selected based on inclusion and exclusion criteria. RESULTS AND CONCLUSION: (1) Using conventional annealing techniques to treat 3D printed titanium alloy specimens, keeping them at 500-900 °C for 2-4 hours, can effectively increase the elongation of 3D printed titanium alloy specimens. (2) Compared to conventional annealing techniques, solid solution aging treatment is more complex, and the titanium alloy specimens after solid solution aging treatment exhibit outstanding yield strength and better corrosion resistance. However, the 3D printed titanium alloy specimens after solid solution aging treatment have no advantage in terms of ductility. (3) Hot isostatic pressing treatment can reduce the internal defects of 3D printed titanium alloy specimens, significantly increase the elongation of 3D printed titanium alloy specimens, and increase their fatigue life. (4) Rapid heat treatment can significantly improve the elongation of 3D printed titanium alloy specimens, and the speed is faster. In terms of elongation improvement and heat treatment efficiency, it has more advantages than conventional annealing in the past. (5) The improvement of elongation of 3D printed titanium alloy specimens by cyclic heat treatment exceeds that of conventional annealing. Cyclic heat treatment can significantly improve the grain structure of 3D printed titanium alloy specimens, but the heat treatment time is too long and the efficiency is low. [ABSTRACT FROM AUTHOR]

The dispersion of silica in rubber systems and its interaction with rubber are two key factors in the preparation of rubber composites with excellent properties. In view of this, silica modified with terminal isocyanate-based polybutadiene liquid rubber (ITPB) is used to improve the dispersion effect of silica in rubber and enhance its interaction with the rubber matrix to improve the rubber's performance. The impact of different modification conditions on the dispersion of silica and the properties of modified silica-filled rubber composites were studied by changing the amount of ITPB and the modification method of silica, including blending and chemical grafting. The experimental results show that ITPB is successfully grafted onto silica, and the use of modified silica improves the cross-linking density of rubber, promotes the rate of rubber vulcanization, and overcomes the shortcomings of the delayed vulcanization of silica itself. When the ratio of ITPB liquid rubber to silica equals 1:20, the comprehensive performance of rubber is the best, the ITPB-modified silica has a better dispersion effect in rubber, and the rolling resistance is slightly improved, with tensile strength reaching 12.6 MPa. The material demonstrates excellent overall performance and holds promise for applications in the rail, automotive, and electrical fields. [ABSTRACT FROM AUTHOR]

Cu alloys have been widely used in the manufacture of liners because of their high density, good plasticity, and excellent thermal conductivity. In order to achieve excellent jet stability and penetration performance, it is necessary to further improve the mechanical properties of Cu-based liners. Nevertheless, the simultaneous enhancement of strength and ductility of the Cu alloys remains a huge challenge due to the strength–ductility trade-off phenomenon of metals/alloys. In this study, the microstructure evolution of rare earth Nd-modified Cu alloy and its effect on mechanical properties were investigated using OM, SEM, EBSD, and TEM techniques. The results show that the ultimate tensile strength (218 MPa) and elongation (50.7%) of sample 1 without Nd are the lowest. With increasing Nd content; the tensile strength and elongation of the samples increase; and the mechanical properties of sample 4 are the best, with a tensile strength of 278.6 MPa and elongation of 65.2%. In addition, with the increase in Nd content, not only is the grain size of the Cu-Nd alloy refined, but also the strength and plasticity are improved so that the strength–ductility trade-off phenomenon is improved. The strength improvement is mainly attributed to grain refinement strengthening, dispersion strengthening, and strain hardening. The increase in ductility is mainly related to the improvement of the microstructure heterogeneity by the Nd element. [ABSTRACT FROM AUTHOR]