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Mn3Sn is an anomalous Hall effect (AHE) antiferromagnet that exhibits the hysteretic AHE in antiferromagnetic (AFM) phase at room temperature. We report that whisker Mn3Sn crystals grown by the flux method exhibit a non-hysteretic AHE at mid-to-low temperatures when the whisker Mn3Sn is surrounded by a thin layer of ferromagnetic Mn2−xSn. These crystals exhibit a hysteretic AHE above 275 K due to the spin alignment of the inverse triangular lattice, which is similar to other crystals. However, upon cooling the crystal, it exhibits a non-hysteretic AHE with a spiral AFM spin structure at 100–200 K. We concluded that the non-hysteretic AHE is induced at the interface of Mn2−xSn/Mn3Sn. We believe that the scalar-spin chirality in the spiral AFM phase of Mn3Sn, modulated by Mn2−xSn through the magnetic proximity effect, produces the AHE. This discovery opens a new avenue for tailoring the AHE by magnetic layers. [ABSTRACT FROM AUTHOR]

Magnesium borate whiskers were used to prepare a hierarchical microstructure on cordierite ceramic substrate through the precipitation-molten salt method. The La 2-X Ce X Zr 2 O 7 catalyst was then loaded onto the magnesium borate whiskers to form the hierarchical microstructure. The Ce-doped catalysts exhibited a significant improvement in the catalytic activity of soot combustion compared to the La 2 Zr 2 O 7 catalyst. The study employed various techniques to characterize the structural morphology and phase composition, including scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Fourier transform-infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The growth of Magnesium borate whiskers (Mg 2 B 2 O 5) with diameters of 100–200 nm and lengths of 2–5 μm were grown and tightly bonded to the cordierite ceramic substrate to mimic the structure of human respiratory system cilia. This could improve the filtration efficiency of soot in car exhaust. BET analysis showed that the specific surface area of cordierite increased from 0.684 m2/g to 1.363 m2/g after whisker growth. The study confirmed that the whiskers were firmly attached to the cordierite ceramic substrate, as demonstrated by the binding strength experiments. The addition of Ce metal has been found to significantly enhance soot combustion due to the presence of more active oxygen species and superior mobility of lattice oxygen species with more oxygen vacancies. The catalyst's intrinsic redox property was characterized using X-ray photoelectron spectroscopy (XPS) and H 2 temperature-programmed reduction (H 2 -TPR). The semi-quantitative thermogravimetric analysis (TG-DTG) and the temperature-programmed oxidation (TPO) of catalysts showed that Z-La 1.9 Ce 0 · 1 Zr 2 O 7 exhibited the highest catalytic activity for soot combustion, with an ignition temperature of 268 °C, a peak temperature of 418 °C, and a temperature of 90 % soot conversion of 464 °C. Furthermore, cyclic stability experiments demonstrate that the Z-La 1.9 Ce 0 · 1 Zr 2 O 7 catalyst exhibits excellent structural stability and consistent catalytic performance. This distinctive microstructure holds great potential for applications in the field of DPF. [ABSTRACT FROM AUTHOR]

• LNF exhibited a high freezing rate and contributed to small ice crystal forming. • LNF maintained WHC and shear force of Monopterus albus. • LNF alleviated myofibrillar protein denaturation of Monopterus albus. • LNF at −110 °C is more suitable for Monopterus albus than LNF at −50 °C and −80 °C. Monopterus albus is highly susceptible to spoilage due to high protein and moisture contents while frozen storage can effectively prolong the shelf-life. To study the effect of liquid nitrogen freezing (LNF) on quality, microstructure of ice crystal and muscle fiber, and physicochemical properties of proteins, Monopterus albus was frozen at -20 °C by refrigerator (RF, control), -50 °C, -80 °C, and -110 °C by LNF, respectively. The -110 °C LNF exhibited the highest freezing rate among four groups, contributing to the formation of small ice crystals with more uniform distribution and alleviating the damage to muscle fiber. In -110 °C LNF group, protein secondary structure changed relatively subtle, resulting in high protein solubility, Ca2+-ATPase activity, and total sulfhydryl content, as well as low surface hydrophobicity and disulfide bond content. LNF retarded the rise of TVB-N value, prevented the loss of immobilized and free water, and maintained water holding capacity and shear force. In conclusion, -110 °C LNF was recommended a promising freezing process for frozen Monopterus albus due to less alteration of quality and alleviation of protein denaturation. [Display omitted] [ABSTRACT FROM AUTHOR]

The green and efficient use of coal gangue (CG) is urgently required in the Chinese coal industry to avoid its adverse environmental impact. This study proposed an Al-assisted carbothermal reduction method to synthesise SiC–Al 2 O 3 ceramics using high-C CG. The optimised experimental conditions for sintering SiC and their effects on the phase composition and related properties of the composites were investigated. The addition of Al optimised the in-situ synthesis pathway of SiC and significantly improved the carbothermal reaction efficiency, making the reactive temperature decrease from 1500 to 1200 °C. Additionally, sintering temperatures could modulate the SiC morphology by affecting the generation of SiO (gas) and the liquid phase of melting Al. The H3 formulation sintered at 900 °C was appropriate for producing SiC w /Al 2 O 3 ceramics with a bending strength of 49.24 MPa, a thermal conductivity of 1.720 W (m K)−1 and good thermal shock resistance (no cracks forming after 20 cycles). This study aimed to fully combine the reactivity changes of CG with the melting reduction reaction of Al. Findings in this work offer novel insights into the synthesis of structural ceramics and the cleaner use of CG for solar thermal storage. [ABSTRACT FROM AUTHOR]

A TiN whisker toughening TiB 2 based ceramic composite was fabricated by spark plasma sintering (SPS). The influence of sintering temperature and holding time on the microstructure and mechanical properties of the composite was investigated. The results indicate that, at a sintering temperature of 1500 °C and a holding time of 9 min, the composite exhibits a relative density of 99.24 %, flexural strength of 906 MPa, fracture toughness of 8.6 MPa m1/2, and Vickers hardness of 22.3 GPa. The sintering aid composed of Ni and Mo within the composite significantly enhanced atomic diffusivity in TiB 2 grains, promoting a balanced grain growth rate. SPS technology promoted the rapid formation of numerous necks between TiB 2 grains in a very short duration. Concurrently, the pinning effect exerted by TiN whiskers effectively inhibited excessively rapid migration of grain boundaries. These factors ensured that the composite could achieve optimized microstructures and good mechanical properties at a low sintering temperature. [ABSTRACT FROM AUTHOR]

Ceramic whiskers exhibit excellent performance due to their special structure, making them widely used in the field of refractories. In this work, a novel Al 4 SiC 4 whisker was designed to improve the mechanical properties and thermal shock resistance of Al 2 O 3 –SiC–C (ASC) refractories. By introducing nickel nitrate as a catalyst, the Al 4 SiC 4 whiskers with a special "stalactite" structure could be directly grown in situ at the operating temperature of ASC (1450 °C). Combining the experimental results and first-principles calculations, the AlNi 2 Si alloy formed during the heat treatment process acted as catalyst sites, AlO, SiO and CO were easily absorbed on the Ni 55 surface. Subsequently, the Al–O, Si–O and C–O bonds were broken and reacted with each other to grow Al 4 SiC 4 whiskers according to the vapor-liquid-solid mechanism. As expected, the incorporation of Al 4 SiC 4 whiskers resulted in a 57.4 % increase in cold compressive strength (CCS) and a 47.2 % increase in residual strength ratio (RSR) of the ASC refractories due to the strengthening mechanism of whisker bridging. This study presents a novel research strategy for enhancing the properties of refractories. [ABSTRACT FROM AUTHOR]

Aluminum nitride (AlN), prized for its high thermal conductivity and electronic insulating properties, finds widespread use in electronic applications, particularly as a substrate material. However, its relatively low fracture toughness limits its application. In this study, to enhance both the thermal and mechanical properties of AlN ceramics, we thoroughly investigate the microstructure, thermal, and mechanical properties of self-reinforced AlN ceramics fabricated by spark plasma sintering, with self-reinforcement achieved through the integration of AlN whiskers within the AlN matrix. Unlike previous studies utilizing conventional pressureless sintering with limited sintering conditions, this work employs spark plasma sintering with a wide range of temperatures (1600–1900 °C) and holding times (10–30 min), providing a comprehensive understanding of the sintering behavior. Microstructural features, observed through optical and scanning electron microscopy, reveal distinct toughening mechanisms via crack deflection and branching, with a maximum 20% enhancement. The self-reinforced AlN ceramics exhibit remarkable improvements in thermal conductivity, reaching up to 150 W m−1 K−1, surpassing reported values for spark plasma-sintered AlN ceramics. Adding AlN whiskers enhances the thermal and mechanical properties of AlN simultaneously, particularly at 1800 °C for 10 min with controlled grain size and nicely integrated AlN whiskers. This work not only contributes valuable insights into the complex relationship between processing parameters, microstructure, and resulting thermal and mechanical properties but also highlights the enhanced thermal and mechanical properties of self-reinforced AlN ceramics. [ABSTRACT FROM AUTHOR]

Regulation on one-dimensional growth has been a major challenge for the preparation of high quality zirconia whiskers. In the present work, high-aspect ratio zirconia whiskers were successfully synthesized via molten salt method. The effect of soaking time on the aspect ratio and growth behaviour of zirconia whiskers was studied. The results suggested that the average aspect ratio of zirconia whiskers reached to 42 at 15 h. The zirconia whiskers grew along [100] direction. The entire process can be divided into an initial slow stage, a rapid growth stage and a declining stage. The dissolution–precipitation of Na9-4xZrx(PO4)3 is the key factor in the initial slow stage. The rapid growth stage of zirconia whiskers is highly dependent on the directional adsorption of F− and screw dislocation step. In the declining stage, the drastic transformation of whiskers morphology from fibrous shape to rod-like and granular ones is caused by excessive volatilization of Na3PO4·12H2O and NaF molten salts. [ABSTRACT FROM AUTHOR]

Herein, we investigate the effect of the addition of tetra‐needle‐like zinc oxide whisker (T‐ZnOw), a novel reinforcing additive, on the melt crystallization behavior of biodegradable polybutylene adipate terephthalate (PBAT)/polylactic acid (PLA) polymer blends. PBAT and PLA were blended in a Haake mixer at a fixed weight ratio of 70/30, and the contents of T‐ZnOw varied from 0 to 7 wt%. The melt thermal properties and crystallization behavior of PBAT/PLA blends and PBAT/PLA/T‐ZnOw composites were studied using differential scanning calorimetry. The kinetics of melt crystallization have been quantitatively explained using a range of mathematical formalisms. The Avrami equation is adopted to analyze the isothermal crystallization process and kinetics of PBAT/PLA/T‐ZnOw composites. For its nonisothermal crystallization process and kinetics, the Ozawa equation cannot describe the entire process, while the Jeziomy‐modified Avrami equation can only describe the initial stage of its nonisothermal crystallization. Using Mo‐analysis, the impact of T‐ZnOw contents on the composite's nonisothermal crystallization kinetic has been thoroughly examined. Given that the PBAT/PLA blend system's crystal formation may be inhibited by T‐ZnOw, the observation demonstrates that T‐ZnOw only marginally alters this process. The work is of significant scientific value and adds a new concept to the development of sustainable thin film for packaging. Highlights: T‐ZnOw is used as a novel additive for PBAT/PLA polymer blends.The crystallization of PBAT/PLA/T‐ZnOw composite systems is thoroughly examined.T‐ZnOw marginally reduces the kinetics of the crystallization process of PBAT/PLA blends.PBAT/PLA/T‐ZnOw composites follow volume nucleation with mixed 2D/1D growth.The nonisothermal crystallization of PBAT/PLA/T‐ZnOw composites is validated by Mo‐analysis. [ABSTRACT FROM AUTHOR]

Hydrogen bonding is the prerequisite for polyamide fibers to have better stress–strain behavior. It affects the crystal structure of polyamide fibers, such as orientation and periodic arrangement. To illustrate the effect of intermolecular hydrogen bonding on fiber orientation structure and macroscopic mechanical properties, this work uses conventional polyamide resin doped with high molecular weight components to construct polymer compounds with discrete distribution characteristics. By analyzing the changes in intermolecular hydrogen bonds, melt rheological properties, non‐isothermal crystallization behaviors, the impact of hydrogen bonds on the crystal structure and orientation structure and thus on the fiber strength was clarified. The doping of high molecular weight components can make the compound form more hydrogen bonds and inhibit the relaxation of molecular chains through entanglement, thereby promoting melt non‐isothermal crystallization process and increasing complex viscosity η* and storage mode G'. 1D and 2D wide‐angle and small‐angle X‐ray scattering show that doping components reduce crystal size of α1(200) and α2(002, 202) planes from 4.19 to 3.47 nm and 5.88 to 4.96 nm, resulting in a denser long‐period structure. Through the strategy of this work, polyamide 6 fibers' tensile strength is effectively improved by18%, and the mechanical properties are significantly improved. Highlights: High‐strength polyamide compound fibers were prepared.Discretely distributed compounds are achieved.Discretely distributed molecular weight enabled hydrogen bonding regulation.Hydrogen bonding‐induced compound fiber crystal structure.Multiple external fields induced crystallization and orientation structures. [ABSTRACT FROM AUTHOR]

Commercially pure titanium was plasma paste borided using various temperatures of the process. An increase in the boriding temperature resulted in an increase in the thickness of the borided layer. All the layers produced consisted of an outer compact TiB2 zone and an inner TiB zone in the form of whiskers penetrating into the substrate. The presence of hard titanium borides resulted in a significant increase in wear resistance compared to non-borided pure titanium. However, the thickness of the layer produced strongly influenced the wear behavior, in respect of the time required for complete destruction of the layer. Higher wear resistance was characteristic of the TiB2 layer due to its compact nature, whereas the specific morphology of TiB whiskers resulted in their lower wear resistance compared to the outer TiB2 layer. Plasma paste boriding of pure titanium also had an advantageous effect on corrosion resistance compared to non-borided pure titanium. Simultaneously, due to the higher thickness of TiB2 layer, the specimen borided at a higher temperature showed higher corrosion resistance. [ABSTRACT FROM AUTHOR]

In this paper, linear low-density polyethylene (LLDPE) fibers were stabilized by ultraviolet ray (UV) irradiation, which provided a new treatment method for fabricating carbon fiber precursors. LLDPE chips were blended with a photo-initiator 4-chlorobenzophenone (4-CBP) and a crosslinker 1,2-polybutadiene (1,2-PB) to obtain spun particles, and then they were melt spun into the fibers. Then, UV irradiation of the as-spun fibers was performed to obtain precursors. An orthogonal experimental design investigated the effects of the ingredient ratio LLDPE:1,2-PB and UV irradiation time on the fiber gelation. The results show that the factor's order of influence was: ingredient ratio > UV irradiation time. The fiber gelation reaches a maximum of 67.51% at a dosage ratio of LLDPE:1, 2-PB of 97:2, and a UV irradiation time of 30 min. The UV irradiation introduced the crosslinking structure of LLDPE fibers, and the melting temperature of UV-XLPE fibers shifts toward lower temperatures, and the crystal size of the fibers decreased with increasing UV irradiation time. However, longer irradiation time does not beneficially affect the gelation degree. The low cost and feasible crosslinking method in this study offer the possibility of wide application of low-cost polyethylene-based carbon fibers. [ABSTRACT FROM AUTHOR]

In this paper, we propose an innovative light-powered LCE-slider system that enables continuous self-circling on an elliptical track and is comprised of a light-powered LCE string, slider, and rigid elliptical track. By formulating and solving dimensionless dynamic equations, we explain static and self-circling states, emphasizing self-circling dynamics and energy balance. Quantitative analysis reveals that the self-circling frequency of LCE-slider systems is independent of the initial tangential velocity but sensitive to light intensity, contraction coefficients, elastic coefficients, the elliptical axis ratio, and damping coefficients. Notably, elliptical motion outperforms circular motion in angular velocity and frequency, indicating greater efficiency. Reliable self-circling under constant light suggests applications in periodic motion fields, especially celestial mechanics. Additionally, the system's remarkable adaptability to a wide range of curved trajectories exemplifies its flexibility and versatility, while its energy absorption and conversion capabilities position it as a highly potential candidate for applications in robotics, construction, and transportation. [ABSTRACT FROM AUTHOR]

The use of direct ink writing technology, combined with in-situ grown whiskers, has facilitated the development of 3D-printed ceramic catalyst supports-aluminum borate porous ceramics (ABPCs) with hierarchical pore structures. The optimal slurry consists of 0.2 wt% polycarboxylate, 19 wt% water addition, and 1.2 wt% sodium alginate. The most effective printing parameters are determined to be a 1.0 mm nozzle diameter, 10 mm/s printing speed, 4.0 kPa air pressure, and 0.4 mm layer height. After sintering at 1100 ℃, pure-phase aluminum borate (Al 18 B 4 O 33) ceramics are achieved, leading to the formation of needle-like aluminum borate whiskers. The aspect ratio of whiskers, flexural strength, BET-specific surface area, and photocatalytic activity of ABPCs increase initially and then decrease with increasing sintering temperature. The ABPCs coated with a titanium oxide layer display a photocatalytic degradation rate of 83.92% for methyl orange solution. These results underscore the immense potential of ABPCs in high-temperature catalyst support applications. [ABSTRACT FROM AUTHOR]

Near‐infrared‐II (NIR‐II) phosphors are extensively used as NIR phosphor‐converted light‐emitting diodes across various applications. Nonetheless, their application in fiber communication remains underexplored. Furthermore, efficiency challenges persist in developing broadband NIR crystal fiber amplifiers. A series of the Y3−yAl5−xO12:xCr,yCa2+ phosphors with boosted Cr4+ concentration via calcium charge compensation is synthesized, and the optimized sample is fabricated to crystal fibers to reveal the application of the NIR‐II phosphors to fiber communication. The fabricated Cr4+‐doped crystal fiber, exhibiting broadband Cr4+ emission within 1100–1600 nm, effectively covers the high‐transmission loss region caused by water absorption in the telecommunication band. Comprehensive characterization and analyses of the Cr4+ are discussed. Y2.84Al4.9O12:0.1Cr,0.16Ca2+ crystal fiber, fabricated through phosphor synthesis, pellets’ production, and the laser‐heated pedestal growth method, exhibits superior photoluminescence compared to the commercial Cr4+‐doped Y3Al5O12 crystal fiber. Here the potential of NIR‐II phosphors is highlighted in enhancing fiber communication and valuable insights for their future application are provided. [ABSTRACT FROM AUTHOR]

Zirconium boride (ZrB2) whiskers hold significant potential for toughening ultra‐high temperature ceramics (UHTCs). Yet, their fabrication remains challenging due to limited knowledge of the microstructure evolution. Herein, high‐purity ZrB2 whiskers were successfully prepared by electrospinning combined with carbothermal reduction. Specifically, a precursor solution containing Zr–O–C–B networks stabilized through hydrogen bonds with polyvinyl pyrrolidone was synthesized as a spinnable ZrB2 precursor. High‐purity ZrB2 whiskers with a diameter of ca. 200 nm and a length of 5–10 µm were obtained by precise heat treatment of ZrB2 precursor fibers. In this process, ZrO2 grains formed initially and transformed into ZrB2 grains through carbothermal reduction, which further converted into ZrB2 whiskers through a solid‐liquid‐solid mechanism. To testify to the toughening effect for UHTCs, the ZrB2 whiskers were added into ZrB2 powders and followed by sintering. This strategic addition of 5 wt% ZrB2 whiskers led to a 19% enhancement in the fracture toughness of ZrB2 bulk. This study illuminated the preparation strategy and formation mechanism for ZrB2 whiskers and their application for toughening UHTCs. [ABSTRACT FROM AUTHOR]

Structural color is a remarkable physical phenomenon that exists widely in nature. Unlike traditional color rendering methods, they are realized mainly through micro/nanostructures that interfere, diffract, scatter light, and exhibit long‐life and environmental‐friendly color effects. In nature, a few organisms use their color‐changing system to transmit information, such as courtship, warning, or disguise. Meanwhile, some natural inorganic minerals can also exhibit structural colors. Learning from nature, scientists have achieved large‐scale structural color design and manufacturing technology for artificial photonic crystals. Photonic crystals have a unique microstructure that forms a band gap under the action of the periodic potential field, consequently causing Bragg scattering due to the periodic arrangement of different refractive index media within them. Because of the apparent photonic band gap and the ability to form local photons at crystal defects, photonic crystals have been extensively studied in recent years and have broad application prospects in photonic fibers, optical computers, chips, and other fields. In this review, the research, properties, and applications of photonic crystals in recent years are presented, as well as insight into the future developments of photonic crystals. [ABSTRACT FROM AUTHOR]

Based on mortar composites with a low water–cement ratio, the effects of hybrid aramid fiber (AF), calcium sulfate whisker (CSW), and basalt fiber (BF) on their mechanical properties and wear resistance were studied, and the correlation between wear resistance and compressive strength are discussed. A microstructure analysis was conducted through scanning electron microscopy (SEM) and the nitrogen-adsorption method (BET). The research results show that compared with the control group, the compressive strength, flexural strength, and wear resistance of the hybrid AF, CSW, and BF mortar composites with a low water–cement ratio increased by up to 33.6%, 32%, and 40.8%, respectively; there is a certain linear trend between wear resistance and compressive strength, but the discreteness is large. The microstructure analysis shows that CSW, AF, and BF mainly dissipate energy through bonding, friction, mechanical interlocking with the mortar matrix, and their own pull out and fracture, thereby enhancing and toughening the mortar. A single doping of CSW and co-doping of CSW and AF can refine the pore structure of the mortar, making the mortar structure more compact. [ABSTRACT FROM AUTHOR]

Pavement cracking is a primary cause of early damage in asphalt pavements, and fiber-reinforcement technology is an effective method for enhancing the anti-cracking performance of pavement mixtures. However, due to the multi-scale dispersed structure of pavement mixtures, it is challenging to address cracking and damage with a single fiber type or fibers of the same scale. To investigate the toughening mechanisms and damage behavior of hybrid-fiber-modified mixtures, we analyzed the fracture process and damage behavior of these mixtures using a combination of basalt fiber and calcium sulfate whisker hybrid fiber modification, along with semicircular bending tests. Additionally, digital imaging was employed to examine the fracture interface characteristics, revealing the toughening mechanisms at play. The results demonstrated that basalt fibers effectively broaden the toughness range of the modified mixture at the same temperature, reduce mixture stiffness, increase residual load at the same displacement, and improve crack resistance in the mixture matrix. While calcium sulfate whiskers enhanced the peak load of the mixture, their high stiffness modulus was found to be detrimental to the mixture's crack toughness. The fracture interface analysis indicated that the three-dimensionally distributed fibers form a spatial network within the mixture, restricting the relative movement of cement and aggregate, delaying crack propagation, and significantly improving the overall crack resistance of the mixture. [ABSTRACT FROM AUTHOR]

Foliar fertilization, an effective agricultural practice, involves the application of nutrients directly through droplets on plant leaves. The mechanisms of mass transport and deposition that arise from the drying of a drop determine the distribution of mass on a surface. Understanding these processes is crucial for optimizing foliar fertilization, ensuring even nutrient distribution, and improving crop yields and quality. This study experimentally investigates deposit formation from the evaporation of fertilizer droplets in various configurations: sessile, vertical, and pendant. We explored the effects of initial droplet volume, vapor pressure, and sorbitol presence on the final deposit morphology. The results reveal distinctive morphological patterns. Sessile drops exhibit two types of deposits—central crystal accumulation with fibrous structures or entirely fibrous structures. In contrast, vertical drops display two zones—fibrous structures at the bottom and small aggregates at the top. On the other hand, pendant drops predominantly feature intertwined crystals with peripheral fibrous structures. We found that high vapor pressures (RH = 60%) inhibit deposit formation within 72 h. Furthermore, the study measures relative evaporation time, showing that sessile droplets exhibit the longest evaporation times, followed by vertical and pendant droplets. Texture analysis, based on GLCM entropy, reveals that deposits generated under low vapor pressure (RH = 20%) show no significant differences in their entropy values, regardless of the droplet configuration and its initial volume. However, at intermediate vapor pressure (RH = 40%), entropy values vary significantly with droplet volume and configuration, being higher in sessile drops and lower in vertical ones. Additionally, we investigated the impact of sorbitol on the coating of sessile fertilizer droplets. We find that configurational entropy decreases exponentially with sorbitol concentration, inducing a morphological transition from fibrous structures to dispersed small aggregates. These findings highlight the complexity of pattern formation in fertilizer deposits and their potential implications for optimizing surface coating processes. [ABSTRACT FROM AUTHOR]

In this paper, 3YSZ/alumina composites containing different content of alumina with different forms (powders and whiskers, respectively) were fabricated by flash sintering. The flash sintering behavior and mechanical properties of the composites were characterized and were compared with those prepared by conventional sintering. The onset temperature of the 3YSZ/alumina whiskers composites was lower than that of the 3YSZ/alumina powders composites with identical alumina content. The reason can be attributed to electrical conductivity; the conductivity of the former was lower than that of the latter. For the 3YSZ/alumina powders composites which can be densified by conventional sintering method, their relative density, Vickers hardness and fracture toughness were comparable to those prepared by flash sintering. While for the 3YSZ/alumina whiskers composites where constrained sintering existed, the flash sintering method revealed obvious advantage over the conventional sintering. A relative density of 94.5 %, hardness of 13.77 GPa and fracture toughness of 5.36 MPa m1/2 were obtained for the flash sintered 3YSZ/30 vol% alumina whisker composites. In contrast, the relative density, hardness, and fracture toughness of the conventional sintered ones were 86.4 %, 11.60 GPa and 4.82 MPa m1/2, respectively. [ABSTRACT FROM AUTHOR]

Quasi‐one‐dimensional (quasi‐1D) van der Waals crystal fibrous red phosphorus (RP) exhibits pronounced in‐plane optical anisotropy, positioning it as a potential candidate for polarization‐related micro‐nano devices. Unfortunately, a comprehensive investigation into the complex refractive index of fibrous RP and the structure–activity relationship connecting the distinctive quasi‐1D structure with optical anisotropy is currently deficient. Herein, we have collectively determined the complex refractive index of the fibrous RP flakes within the ab‐plane through Kramers–Kronig (KK) analysis and theoretical calculation. Notably, the maximum birefringence of fibrous RP reaches 0.642@475 nm with an absolute extinction coefficient of only 0.08, superior to the reported traditional optical crystals and the emerging low‐dimensional materials as well. The remarkable birefringence can be attributed to the synergistic influence of the large electronic dipole polarizability, anisotropic electron density distribution and the distortion of stereochemically active lone pair (SCALP). This work demonstrates the potential of fibrous RP for polarization‐sensitive devices, illuminating possibilities to exploit novel giant birefringent crystals based on the structure–activity relationship. [ABSTRACT FROM AUTHOR]

The network microstructure titanium matrix composites (NMTMCs) exhibit excellent properties but research on its machining remains limited. In this paper, single and continuous pulse electrical discharge machining (EDM) experiments were conducted on the NMTMCs composed of Ti6Al4V matrix combined with 5% vol. network distributed TiB whisker (TiBw). The impact of TiBw on EDM was analyzed in comparison to the machining results of pure Ti6Al4V. The results indicate that the TiBw reinforcements absorbs pulse energy during the machining process, resulting in smaller areas and more complex morphologies for the EDM craters. Based on this, a linear absorption model for pulse energy by reinforcement strips is proposed. Furthermore, in continuous pulse EDM with low capacitance settings, the presence of TiBw tends to generate micro pores on the surface and reduce material removal rate (MRR). However, when using higher capacitance settings, MRR for NMTMCs can surpass that achieved for pure Ti6Al4V. [ABSTRACT FROM AUTHOR]

The advent of flexible electronics has prompted the development of functional fibers with superior mechanical and electrical properties. MXenes, a novel family of 2D functional materials, have a variety of potential applications in flexible electronics. Herein, wet‐spinning is employed to continuously assemble Ti3C2Tx MXene liquid crystals into macroscopic fibers. Meanwhile, Zn2+ is introduced into the fiber to eliminate the electrostatic repulsion between the MXene nanosheets and enhance interlayer interactions and sheet alignment. The as‐obtained MXene fibers have strong mechanical strength (150.7 MPa), high electrical conductivity (3637.9 S cm−1), and good flexibility that facilitates weaving and knotting, making them suitable for fabric‐like flexible devices. The sound pressure sensors are woven from MXene fibers, which feature quick response time (286 ms) and recovery time (642 ms), ultra‐high sensitivity (280.2 kPa−1), and a low detection limit (0.1 Pa). Sound detection and recording are achieved using this sensor. MXene fibers as wearable thermal management devices are also demonstrated, exhibiting fast Joule thermal responses and good cycling stability. [ABSTRACT FROM AUTHOR]

Biomaterials, like hydroxyapatite (HAp), are the subject of many scientific investigations. Their specific application, however, is determined by the form and some characteristic features of the resulting material. Synthesis methods and optimization procedures leading to a product of predetermined characteristics are therefore of great interest. To broaden the existing knowledge, sonoprecipitation was investigated as a potential method for the production of nanosized HAp particles. The research was carried out in a static mixer (STM) immersed in the ultrasonic bath. The influence of operating conditions, e.g., ultrasonic power PUS (εUS), ultrasonic frequency (fUS), and unit mixing power (εmix), was investigated in terms of nucleation intensity, product quality, and characteristics (particle size distribution (PSD), mean size, shape, etc.). As a result, the optimal conditions for the HAp nanoparticles synthesis (mean size: d~150 nm; length: L1~250 nm; width: L2~80 nm) in the form of needles/whiskers/rods—similar to the shape of the HAp present in natural human bones, free from agglomerates, with negligible signs of particle destruction—were determined. The formation of HAp of smaller sizes (d ≤ 100 nm) and more compact shapes (L1~155 nm, L2~90 nm), useful in bone regeneration processes, was also discussed. [ABSTRACT FROM AUTHOR]

In this paper, research was conducted to evaluate and analyze the macromechanical properties and micromechanism of stone mastic asphalt (SMA) containing an eco-friendly fibrous substance, calcium sulfate whisker (CSW). The investigation included the preparation of SMA specimens containing the lignin fiber (0.3% by wt. of mixture) and CSW (0%, 6%, 8%, and 10%, by wt. of asphalt binder). Then, wheel tracking, low-temperature flexural bending, Marshall immersion, freeze-thaw indirect tensile strength, and flexural bending fatigue tests were carried out to evaluate the pavement performance of these mixtures. Scanning electron microscopy (SEM) analysis were selected to observe the microstructure and micromorphology of the mixture. The results of laboratory tests revealed that the rutting resistance, moisture susceptibility, and fatigue performance of SMA were improved by the addition of CSW, while the crack resistance at low temperatures decreased slightly. The flexural bending tensile strain, tensile strength ratio, and fatigue life of the mixtures (under different stress levels) showed a trend of initial increase followed by a decrease with increasing CSW content, while optimal results were present at 8% CSW. SEM images revealed that CSW and lignin fiber were uniformly distributed and formed a three-dimensional network structure. Besides physical infiltration and adsorption effects, an anchoring force similar to the mechanical bonding force also existed between CSW and asphalt binder. The economic benefit analysis indicated that SMA with 8% CSW showed the most cost-effective performance. Consequently, about 8 percent should be the ideal CSW content. The outcomes provide critical insights into improving the performance of SMA pavement and serve as an important reference for the development of sustainable pavement. [ABSTRACT FROM AUTHOR]

Thermal analysis of polyacrylonitrile (PAN) fibers is commonly employed to assess the chemical and physical changes occurring during the pre-oxidation stage. However, in actual pre-oxidation processes, PAN fibers are stretched to a certain extent (approximately 5%) to prevent fiber shrinkage. Consequently, the pre-oxidation process of PAN fiber is influenced not only by temperature and atmosphere but also by the stretching tension. In this study, two types of PAN fiber samples with different crystal structures were utilized alongside four different processing methods (PAN powder, unfixation, physical fixation, and chemical fixation) to generate three degrees of fixed stretching. These included PAN powder and unfixed PAN fiber samples (without fixation tension), physically fixed PAN fiber with relatively weak fixation tension, and chemically fixed PAN fiber with strong fixation. Through a comparison of these samples, it was observed that the fixation tension aided in preserving the crystal structure during the heating process, significantly reducing the cyclization rate of the PAN fibers. The cyclization reaction rate of PAN fiber A, initially at 85% without any fixation, decreased to 66% after physical fixation and dropped to 56% after chemical fixation. For PAN fibers with distinct crystal morphologies, the impact of the fixation tension was more prominent for PAN fibers with larger crystal sizes and lower orientation. Additionally, the presence of crystal orientation facilitated the occurrence of the cyclization reactions. [ABSTRACT FROM AUTHOR]

Recent works exploiting photonic valley Hall effect show that large-area topological states can be realized by inserting gapless photonic crystal structures into topological interfaces, thus effectively introducing mode width degree of freedom. However, the previously reported works focus on gapless edge states. It is rare to investigate gapped edge states, especially large-area gapped edge states. In this paper, large-area gapped edge states in a valley photonic crystal heterostructure are achieved and experimentally proved. Compared with large-area gapless topological states, the present gapped edge states are more localized, which provides a more effective way to manipulate electromagnetic waves. We implement a topological energy concentrator and topological resonator cavity based on the large-area topological transmission with the gapped edge states. It is expected that our results broaden photonic systems, which can be used in topological lasing, field enhancement, and high-capacity energy transport. [ABSTRACT FROM AUTHOR]

Implant materials with micro/nanostructures bear a closer resemblance with the features of natural bone, which influences the wettability, bone differentiation, and vascularization of materials. However, it is still technically challenging to design the inner wall and surface micro/nanostructures on macroporous bioceramics due to their brittleness. In this work, micro/nanostructured composites with Si3N4 whiskers as a framework, and the (inner) surface covered with SiC nanowires were prepared, denoted as SiC‐nw@Si3N4‐w bioceramics. The synthesis, adopting the green chemistry concept, was utilized from environmental products (carbon evaporated in the furnace at high temperature) and reaction impurities (carbon obtained by polymer pyrolysis and silicon obtained by Si3N4 decomposition) to synthesize SiC nanowires via a vapor‐solid growth mechanism. The prepared SiC‐nw@Si3N4‐w bioceramics have potential applications in bone repair due to their cell adhesion and proliferation. [ABSTRACT FROM AUTHOR]

The study investigated the phase transformation and microstructural comparison of two types of continuous alumina fibers with varying silica contents. These fibers were subjected to heat treatment at temperatures of 1100, 1200, 1300, and 1400 °C in air. By comparing the experimental results of the two different fibers, relevant influencing mechanisms were derived. The appearance of mullite phase in the fibers occurred when the heat treatment temperature reached 1200 °C. Variations in silicon content led to inconsistent pinning effects, resulting in differences in the occurrence of irregular structures on the surface of the two types of fibers. Following heat treatment at 1300 °C, the fibers exhibited scale-like and mosaic-like structures, accompanied by phase aggregation. Subsequent heat treatment at 1400 °C resulted in the fibers displaying layered structures composed of α-Al 2 O 3 phase and undergoing significant changes in microstructure. Notably, the two types of fibers exhibited a significant difference in the presence or absence of a glass phase, and the addition of silicon oxide to a certain extent was found to inhibit the crystal transformation of Al 2 O 3. Additionally, the experimental results were analyzed in terms of influencing mechanisms based on theories such as activation energy barriers and total free energy. [ABSTRACT FROM AUTHOR]

In this paper, the heat treatment of alumina fiber was studied. The infiltration agent on the fiber surface was removed after heat treatment at 450 °C for 6 h. TG-DSC, scanning electron microscope, x-ray diffraction, Fourier infrared spectrometer, energy dispersive spectrometer, and patterning were used to analyze the thermal weight loss, fiber surface morphology, crystal structure, and composition of alumina fibers. The results show that the aluminum oxide fiber has excellent temperature resistance and does not undergo crystal phase transformation during thermal weight loss. After heat treatment, the fiber surface infiltration agent ablates and dissolves from the fiber surface, and the internal crystal structure of the fiber remains stable. The tensile testing machine was utilized to test the breaking strength of alumina fiber. The fiber still maintained high strength after heat treatment, and the retention rate of breaking strength was greater than 74%. ZC-90G high insulation resistance measuring instrument and WDY-Ⅱ automatic voltage tester were utilized to analyze the insulation resistivity and breakdown strength of alumina fiber before and after heat treatment. The results show that heat treatment can effectively improve the insulation performance and breakdown strength of alumina fiber. [ABSTRACT FROM AUTHOR]

The presence of organic contaminants in aquatic environments, such as antibiotics, induces the proliferation of resistant pathogens, giving rise to the need to develop new materials with antimicrobial action. Therefore, in this work, we report new results to purified Palygorskite (P-Pal) clay with a surface impregnated with alpha-silver tungstate (α-Ag 2 WO 4) microcrystals abbreviated as AWO, and its structural, photoluminescence (PL) and antibacterial investigation for inactivation of gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacterial strains at concentrations of P-Pal/ x %/AWO from x = 4–32%. X-ray diffraction patterns, Rietveld refinement data, and Fourier transform infrared spectroscopy confirmed that the P-Pal is composed of two crystal phases (Mg 2.074 Al 1.026) (Si 4 O 10.48) 2 (OH) 2 (H 2 O) 10.68 with an orthorhombic structure and α-SiO 2 with a rhombohedral structure; already the AWO microcrystals are single-phase with an orthorhombic structure and their vibrational modes. Ultraviolet–visible spectroscopy shows an increase in the E gap values for mixed systems compared to the isolated materials, indicating a synergistic interaction between the energy levels of both materials. Field emission scanning electron microscopy images display the presence of several elongated fibers and hexagonal crystals in the P-Pal clay and rod-like AWO microcrystals. In contrast, P-Pal clay/AWO microcrystals exhibit the presence of all three crystal shapes. Photoluminescence spectra show a high emission for the P-Pal clay/4% AWO microcrystals, indicating a better energy band gap synergistic. Finally, the microbiological tests show that as the proportion of AWO crystals on the P-Pal clay surface increases, there is a rise in antibacterial activity. [ABSTRACT FROM AUTHOR]

The production of high-performance carbon fibers relies heavily on the structural transformations of polyacrylonitrile (PAN) fiber during processing. In this article differential scanning calorimetry (DSC), synchrotron small-angle X-ray scattering (SAXS), and synchrotron wide-angle X-ray diffraction (WAXD) were used to study the changes of the thermal properties, voids and crystal structure of the PAN precursor fibers on industrial lines during the continuous processing stages, i.e., after the treatment in the coagulation bath, after stretching in boiling water and after stretching in high-temperature steam. The findings of this study suggest that after boiling water stretching the molecular chain motion of the PAN precursor fiber weaken, resulting in the expansion of the voids. After high-temperature steam stretching the voids became elliptical and oriented in the stretching direction. Although the boiling water stretching process partially damaged the (100) crystal planes of the PAN precursor fibers, it does not hinder their overall crystalline structure. The high stretching ratio primarily affected the orientation of the molecular chains. This orientation, even in the context of partial crystal plane disruption, further promoted the crystallization of the (100) crystal planes in the fibers. These experiments explored the correlation between the processing technology and fiber structure transformation of PAN-based carbon fibers, resulting in producing a guide for the preparation of high-performance carbon fibers with fewer defects. [ABSTRACT FROM AUTHOR]

[Display omitted] Orderly hierarchical structure with balanced mechanical, chemical, and electrical properties is the basis of the natural bone microenvironment. Inspired by nature, we developed a piezocatalytically-induced controlled mineralization strategy using piezoelectric polymer poly-L-lactic acid (PLLA) fibers with ordered micro-nano structures to prepare biomimetic tissue engineering scaffolds with a bone-like microenvironment (pcm-PLLA), in which PLLA-mediated piezoelectric catalysis promoted the in-situ polymerization of dopamine and subsequently regulated the controllable growth of hydroxyapatite crystals on the fiber surface. PLLA fibers, as analogs of mineralized collagen fibers, were arranged in an oriented manner, and ultimately formed a bone-like interconnected pore structure; in addition, they also provided bone-like piezoelectric properties. The uniformly sized HA nanocrystals formed by controlled mineralization provided a bone-like mechanical strength and chemical environment. The pcm-PLLA scaffold could rapidly recruit endogenous stem cells, and promote their osteogenic differentiation by activating cell membrane calcium channels and PI3K signaling pathways through ultrasound-responsive piezoelectric signals. In addition, the scaffold also provided a suitable microenvironment to promote macrophage M2 polarization and angiogenesis, thereby enhancing bone regeneration in skull defects of rats. The proposed piezocatalytically-induced controllable mineralization strategy provides a new idea for the development of tissue engineering scaffolds that can be implemented for multimodal physical stimulation therapy. [ABSTRACT FROM AUTHOR]

Highlights Calcium sulfate whiskers (CSW) exhibit significant surface polarity and high surface energy, leading to aggregation when directly incorporated into polymer matrices, significantly affecting the mechanical properties of the composites. Sodium oleate (SO) was used to modify CSW, introducing –C=C– active groups on the surface, followed by in‐situ graft polymerization of sodium oleate‐modified CSW (SO‐CSW) with methyl methacrylate (MMA) to prepare CSW‐g‐PMMA composites. The modification mechanism of SO and PMMA on CSW, as well as the surface modification effects on CSW, were studied using DRIFT, XRD, XPS and TEM. The results show that oleic acid ions adsorb onto the surface of CSW in two forms. One is chemisorption, in which the oleic acid ions are adsorbed on the calcium ions site on the surface of CSW in a bridging way. The other is physical adsorption, oleic acid ions and dissolved calcium ions in the form of precipitation adsorbed on the outermost layer of CSW. After in‐situ polymerization, PMMA was successfully grafted onto the surface of CSW, and the thickness of the surface PMMA coating layer was approximately 67 nm. CSW‐g‐PMMA was used as a filler in the melt blending with polypropylene (PP) to prepare PP composites. CSW‐g‐PMMA mainly toughens and enhances the mechanical properties of PP composites in the form of crack bridging, crack deflection and pull‐out effect. The mechanism of sodium oleate modified calcium sulfate whisker (CSW) has been investigated. One is chemical adsorption that the oleic acid ions are adsorbed on the calcium ions site on the CSW surface in a bridge way. The other is physical adsorption that oleic acid ions and dissolved calcium ions are adsorbed in the form of precipitation on the outer layer of CSW. After the modification of sodium oleate, the active group –C=C– was introduced on the surface of CSW, and then the PMMA long chain polymer was grafted with an in‐situ polymerization to form a PMMA coating layer with a thickness of about 67 nm, which significantly improved the hydrophobicity of CSW surface. After modification with sodium oleate and PMMA grafting, the modified CSW significantly toughened and enhanced the mechanical properties of PP composites in the form of crack bridging, crack deflection and pull‐out effect. [ABSTRACT FROM AUTHOR]

This paper presents the construction of an innovative high-temperature sensor based on the optical principle. The sensor is designed especially for the measurement of exhaust gases with a temperature range of up to +850 °C. The methodology is based on two principles-luminescence and dark body radiation. The core of this study is the description of sensing element construction together with electronics and the system of photodiode dark current compensation. An advantage of this optical-based system is its immunity to strong magnetic fields. This study also discusses results achieved and further steps. The solution is covered by a European Patent. [ABSTRACT FROM AUTHOR]

Ti–5.9Al–4.0Sn–3.5Zr–0.5Mo–0.3Nb–1.0Ta–0.4Si–0.8W–0.05C (Ti65) alloy is a high-temperature titanium alloy designed for service at 650 °C. To further improve the elevated temperature mechanical performance of Ti65, Ti65-based composites have been fabricated in the present study through a low-energy ball milling and reaction hot-press sintering process. Hot compression tests were further performed on the as-sintered TiB/Ti65 composites at the temperature ranging from 1040 to 1100 °C at the strain rate of 1–0.001 s−1. The results show that during deformation at 1–0.1 s−1, dynamic recrystallization was the dominant mechanism. At the low strain rate of 0.01–0.001 s−1, dynamic recovery became the predominant mechanism. Hyperbolic constitutive equations were calculated and the processing maps were constructed based on dynamic material modeling. The activation energy for hot deformation was determined to be 321.57 kJ/mol and the ideal processing parameters for the network composite were 1070–1100 °C with a strain rate of 1–0.1 s−1. The microstructural analysis of the hot compression-deformed samples revealed the presence of two dynamic recrystallization mechanisms: continuous dynamic recrystallization and discontinuous dynamic recrystallization. After hot compression, metallic matrix exhibited preferred orientation, including a strong < 1 ¯ 2 1 ¯ 0 > //CD fiber texture and < 01 1 ¯ 1 > //CD fiber texture. Matrix flow induced TiB whiskers rotation, producing a pronounced [ 100 ] //CD texture and a weak [ 010 ] //RD and [ 010 ] //ND texture. [ABSTRACT FROM AUTHOR]

Self-vibrating systems obtaining energy from their surroundings to sustain motion can offer great potential in micro-robots, biomedicine, radar systems, and amusement equipment owing to their adaptability, efficiency, and sustainability. However, there is a growing need for simpler, faster-responding, and easier-to-control systems. In the study, we theoretically present an advanced light-actuated liquid crystal elastomer (LCE) fiber–mass system which can initiate self-sliding motion along a rigid circular track under constant light exposure. Based on an LCE dynamic model and the theorem of angular momentum, the equations for dynamic control of the system are deduced to investigate the dynamic behavior of self-sliding. Numerical analyses show that the theoretical LCE fiber–mass system operates in two distinct states: a static state and a self-sliding state. The impact of various dimensionless variables on the self-sliding amplitude and frequency is further investigated, specifically considering variables like light intensity, initial tangential velocity, the angle of the non-illuminated zone, and the inherent properties of the LCE material. For every increment of π/180 in the amplitude, the elastic coefficient increases by 0.25% and the angle of the non-illuminated zone by 1.63%, while the light intensity contributes to a 20.88% increase. Our findings reveal that, under constant light exposure, the mass element exhibits a robust self-sliding response, indicating its potential for use in energy harvesting and other applications that require sustained periodic motion. Additionally, this system can be extended to other non-circular curved tracks, highlighting its adaptability and versatility. [ABSTRACT FROM AUTHOR]

Sintering red mud (SRM) is an industrial alkaline waste residue generated from the sintering process in alumina production, which is often directly discarded and causes environmental issues. In this study, an innovative magnesium-modified wet carbonation method was proposed to convert sintering red mud to valuable calcium carbonate whiskers using CO 2 -containing flue gas. The effects of carbonation conditions including temperature, MgCl 2 concentration, and duration on the composition, microstructure, and morphology of carbonated products were systematically investigated. It was found that a high whisker content of 60% with an aspect ratio of ∼6 could be obtained under the optimal conditions of 80 °C, 0.4 M MgCl 2 , and 2 h reaction time. Besides the formation of whiskers, amorphous aluminosilicate gel was also generated during SRM carbonation. The effects of the as-prepared whisker-rich materials as partial cement replacement on the mechanical properties of cement paste were evaluated with 5 wt% replacement, the 28 d compressive strength was significantly improved by 20.5% compared to the control specimen. The effective reinforcement was ascribed to the fibrous whiskers and enhanced interfacial bonding. This method enables high-value utilization of SRM waste and CO 2 fixation, providing a green and low-cost approach to producing high-performance cementitious materials. [ABSTRACT FROM AUTHOR]

This study aims at an innovative sample preparation strategy for fiber reinforced thermoplastic (FRTP) composites analyzed via polarized optical microscopy to visualize the crystalline structure of the matrix resin. Investigating the structure is relevant for understanding the relationship with the mechanical properties. In general, polarized optical microscopy is a powerful technique for visualizing polymer crystalline structures at samples sliced into thin sections below 30 μm. However, analyzing FRTPs remains challenging in absence of suitable methods for the preparation of thin sections owing to the embedded fibers. Herein, the preparation of appropriately thin sections in a novel sequence of steps is shown that may generically be applied to FRTPs. Four different types of FRTPs with major matrix resins (GF/PBT, CF/PA6, CF/PEEK and GF/PP) were successfully processed to thickness of 5 μm or below without fiber loss, resin breakage or delamination between fiber and resin demonstrating the utility of the developed method, which is the significant outcome of the study. To the best of our knowledge, the subsequently obtained polarized optical microscopic images for the first time visualized the crystalline structure of the matrix resin revealing nucleation of crystals from the fiber surface and effects of mold flow on the crystallization behavior. Highlights: Thinning of fiber reinforced thermoplastics to thickness of 5 μm or below.Thinning achieved despite fiber volume at industrial applications level.Sample preparation ensures ideal conditions for polarized optical microscopy.Visualization of crystalline structure of the matrix resin for the first time.Potential advancement for spectroscopic and electron microscopic analyses. [ABSTRACT FROM AUTHOR]

The in-situ TiB whiskers (TiBw)-reinforced TC18 composite was fabricated using spark plasma sintering (SPS), then the effects of solution and aging treatment (2HT), solution and two-step aging treatment (3HT) on the microstructure and mechanical properties of the composite were investigated, respectively. The results showed that the α-phase microscale concentration control can be successfully achieved by different heat treatments. Concretely, a large amount of rod-like α-phase (α p) and needle-like α-phase (α s) were precipitated during the 2HT process. After the 3HT, the coarser α p formed a dense micro-network structure in the composite, while αs disappeared. Compared to the TiBw/TC18 composite, the ultimate tensile strength (UTS) of the 2HT composite increased by 11%, which is the result of the dense α s and α p co-hindering the dislocation movement, and the ductility of the composite increased by 221% after 3HT, which is the result of the coarsened α p blunting the crack tip, consuming the crack expansion energy and slowing down the crack expansion rate. By designing different heat treatment processes, this study aims to guide the suitability of TC18 composites under different working conditions. [ABSTRACT FROM AUTHOR]

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Long Ag and Cu whiskers are found in Ag–Cu–Te alloys annealed at 400 and 600 °C. Depending upon the nominal compositions of the alloys, there are three kinds of whiskers, Ag, Cu, and Ag + Cu whiskers. For the first time, two different kinds of whiskers grown simultaneously from the same substrate are observed. These whiskers are all polycrystalline, and the grain sizes of the Ag are larger than those of Cu. As indicated by their continuous connection with the substrate, many shear bands in the whiskers, and low-angle grain boundaries piling up near the grain boundaries, it is confirmed that the whiskers grow not from the gas phase, but within the solid state, pushed outward by stress. The Ag–Cu–Te liquidus projection is calculated by the Calphad method. It is found that the compositional regimes of whisker growth overlap with the regions of the liquid miscibility gaps. When alloys solidify through a liquid miscibility gap, two regions of different compositions would form. The stress developed following solidification, originating from these two regions of different compositions, is the main driving force behind whisker formation. The rapid growth rates of the whiskers are a result of the rapid liquid-like diffusion behaviors of the Ag and Cu atoms in the Ag–Cu–Te alloys of the cage-like structures. [ABSTRACT FROM AUTHOR]

Network microstructure titanium matrix composites (NMTMCs), featuring Ti6Al4V as the matrix and network-distributed TiB whiskers (TiBw) as reinforcement, exhibit remarkable potential for diverse applications due to their superior physical properties. Due to the difficulty in machining titanium matrix composites, electrical discharge machining (EDM) stands as one of the preferred machining techniques for NMTMCs. Nevertheless, the compromised surface quality and the recast layer significantly impact the performance of the workpiece machined by EDM. Therefore, for the purpose of enhancing the surface quality and restraining the defects of NMTMCs, this study conducted comparative EDM milling experiments between NMTMCs and Ti6Al4V to analyze the effects of discharge capacitance, charging current, and pulse interval on the surface roughness, recast layer thickness, recast layer uniformity, and surface microcrack density of both materials. The results indicated that machining energy significantly influences workpiece surface quality. Furthermore, comparative experiments exploring the influence of network reinforcement on EDM milling revealed that NMTMCs have a higher melting point, leading to an accumulation phenomenon in low-energy machining where the reinforcement could not be completely removed. The residual reinforcement in the recasting layer had an adsorption effect on molten metal affecting the thermal conductivity and uniformity within the recasting layer. Finally, specific guidelines are put forward for optimizing the material's surface roughness, recast layer thickness, and uniformity, along with minimizing microcrack density, which attain a processing effect that features a roughness of Ra 0.9 μm, an average recast layer thickness of 6 μm with a range of 8 μm, and a surface microcrack density of 0.08 μm−1. [ABSTRACT FROM AUTHOR]

Porous Si 3 N 4 ceramics with an interconnected pore structure were prepared by a paraffin emulsified suspension method. The effects of the volume ratio of paraffin to silicon and Y 2 O 3 addition on the structure and properties of porous Si 3 N 4 were studied. Uniform dispersed pores introduced by the emulsified paraffine droplets can be observed in the green samples. With the increase of the volume ratio of paraffin to silicon, the bulk density and the strength of the sample were decreased, and the apparent porosity and Darcy permeability were increased. The formation of α-Si 3 N 4 whiskers could be promoted by the addition of the Y 2 O 3 during the nitriding process, and numerous nano whiskers could be obtained in the pores left by the paraffine droplets with suitable addition of the Y 2 O 3. The porous Si 3 N 4 with interconnected whiskers prepared via the paraffin emulsion method exhibited potential application for hot gas particular matter filtration. [ABSTRACT FROM AUTHOR]

The development of additive manufacturing technique provides possibility to prepare SiC ceramics with complex shapes. However, defect control in the debinding and sintering stages is still a great challenge for the vat photopolymerized components. Here, SiC ceramics were manufactured by vat photopolymerization followed by liquid silicon infiltration, using SiC whiskers as the reinforcement. In the debinding stage, the SiC whiskers prevented the propagation of micro-cracks that induced by the formation and emission of gaseous substance. Also, the SiC whiskers provided channels for the infiltration of liquid silicon during sintering, thus the bulk density of the as-sintered SiC w /RBSC composite reached 2.95 g/cm3 at the whiskers fraction of 8 wt%. Because of the various toughening mechanisms introduced by SiC whisker, the flexural strength and Vickers hardness of the composite increased up to 352.2 MPa and 17.54 GPa, respectively. Thus, this work provides a new strategy to control micro-defects in vat photopolymerized SiC ceramics. [ABSTRACT FROM AUTHOR]

This study investigated converting abundant paper mill waste, de‐inked paper sludge (DPS), into value‐added medium‐density fiberboard (MDF) panels. The objective was to repurpose this solid waste into a valuable material that aligns with the principles of a circular economy. Previous research has examined the addition of paper sludge to wood composites, but there is limited information on the specific incorporation of DPS into MDF production. This investigation offers new insights into this application. MDF panels were manufactured using hardwood fibers, with varying levels of urea‐formaldehyde resin (10% and 12% by weight) and different loadings of DPS (ranging from 0% to 50% by weight). X‐ray diffraction analysis revealed the presence of defective DPS fiber crystals. Contact angle measurements confirmed that DPS had poor wettability, corresponding to increased water absorption. As more DPS was incorporated, the mechanical properties of the panels progressively weakened due to defective fibers and poor adhesion between the fibers and the matrix. This was evident in scanning electron microscopy micrographs, which showed an escalation in interfacial flaws. Increasing the resin dosage noticeably improved the internal bond strength and reduced moisture uptake across all levels of DPS. However, at a DPS loading of 50%, the properties of the panels deteriorated by 36%–57% compared to the control MDF. Additionally, thickness swelling and water absorption increased significantly with higher DPS content, primarily due to the hydrophilic nature of the fibers. Based on optimization, it was determined that a DPS loading of 20% with a resin content of 12% provided the best balance between performance, waste utilization, cost, and moisture resistance. The reuse of abundant paper sludge supports the goals of a circular economy. However, strategies are required to tailor the processing methods and enable higher levels of recycled material without excessively compromising the key attributes of the product. Further research should focus on enhancing the quality of DPS and its compatibility with wood fibers and resin to enhance the performance of the composite material. Highlights: DPS from recycled paper mill assessed for MDF production with wood fibers and resinIncreasing DPS loading caused reductions in strength and adhesion of panelsWater absorption and thickness swelling markedly rose with more DPS additionIt was attributed to hydrophilic fibers and disrupted fiber‐matrix bondingOptimal formulation was 20% DPS loading and 12% resin content, balancing performance, waste utilization, and cost. [ABSTRACT FROM AUTHOR]

Liquid crystal elastomers (LCEs) with photo‐responsive properties, typically driven by either photochemical or photothermal mechanisms, have found extensive applications as, for example, actuators in soft robots. However, intricate temperature‐dependent viscoelasticity of LCEs poses a challenge, leading to a notable gap in the domain of dynamic models for photothermal‐responsive LCE (PTR‐LCE) fibers. Here, a fundamental framework is proposed for accurate modeling and real‐time simulations of PTR‐LCE fiber dynamics. The PTR‐LCE fiber is described as a one‐dimensional (1D) string model that decomposes the fiber deformation into active and passive parts, which are characterized by an order parameter and a temperature‐dependent linear viscoelasticity model, respectively. Then, independent experimental measurements of model parameters are conducted, and a numerical algorithm is developed to solve the model, which is validated for convergence, time efficiency, and accuracy. Finally, the model is employed to simulate both open‐loop and Proportional‐Integral‐Derivative (PID) control of actuators made of PTR‐LCE fibers. The results confirm the advantages of this model over previous models. This work not only reveals the physical mechanisms underlying the PTR‐LCE fiber dynamic behaviors but also provides inspirations for more efficient and precise soft robotic applications. [ABSTRACT FROM AUTHOR]

The rapid development of micro-electronics has a growing demand on the heat dissipation performance of devices, especially thermal management materials. However, recent researches focus on the improvement of single ability, such as thermal or mechanical properties. Herein, a strategy that simultaneously improves thermal and mechanical performance of thermal manager material was proposed, which was achieved by preparing Cu-SiC w composites via the co-electrodeposition technology. The influence of electroplating parameters, such as temperature, current density and reinforcement contents, on the microstructure evolution, mechanical and thermal conductivity were investigated systematically. The fabricated SiC w composite displayed excellent shear strength up to 420 MPa, which is resulted from the Orowan strengthening and load transferring. Additionally, the thermal conductivity of 340 W/(m·K) was obtained, owing to the uniform distribution of whiskers and good interface between the Cu matrix and whiskers. Therefore, the presented work provided an effective method for fabricating comprehensive thermal-mechanical properties and homogeneous heat dissipation capacity Cu-SiC w composites and paved the way for the practical application in the field of the connector between the power devices and heat sinks. [ABSTRACT FROM AUTHOR]

High entropy carbide ceramics have attracted much attention because of their high hardness and chemical inertness, but the relatively low fracture toughness limits their actual industrial applications. In this work, high entropy (MoTaTiVW)C 5 ceramics reinforced with silicon carbide whisker (SiC w) were fabricated with spark plasma sintering. The effects of SiC w contents and sintering temperatures on the microstructure and mechanical properties of (MoTaTiVW)C 5 have been studied. The outcomes show that by optimizing the sintering temperature, a dense microstructure with intact SiC w were obtained which could fully utilize the toughening effect of the SiC w and thus exhibits an enhanced mechanical property. Additionally, the presence of solid solution oxide particles in the sintered bulks is also beneficial for the improved toughness. The sample with 5 wt% SiC w sintered at 1700 °C exhibited higher hardness of 19.63 GPa and fracture toughness of 6.26 MPa m1/2, which is attributed to the combined toughening effects (crack deflection, crack bridging, and whisker/particle extraction) of SiC w and oxide particles. The findings contribute to the development of advanced ceramic materials with improved mechanical properties for various applications. [ABSTRACT FROM AUTHOR]