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The all‐solid‐state lithium metal battery is considered the next‐generation energy storage device with the potential to double the energy density of state‐of‐the‐art Li‐ion batteries and eliminate safety hazards. Achieving stable Li plating/stripping without dendrite propagation within the solid electrolyte is crucial for delivering the promised high energy density. In this study, through the comparison of various synthesis routes, a novel cube‐shaped microstructure in the Li5.3PS4.3ClBr0.7 argyrodite electrolyte, synthesized using the high‐speed mechanical milling followed by annealing method (BMAN‐LPSCB) is identified. The uniform microstructure allows for the production of an electrolyte pellet with significantly reduced porosity through cold pressing. The removal of defects has significantly enhanced the electrolyte's ability to inhibit dendrite formation, with a critical current density reaching 3.8 mA cm−2. The lithium symmetric cell with BMAN‐LPSCB electrolyte exhibits stable Li plating/stripping for over 150 h at a high current density and cutoff capacity of 3 mA cm−2 / 3 mAh cm−2. The all‐solid‐state Li/NCM battery utilizing the BMAN‐LPSCB electrolyte also demonstrates excellent durability, with a capacity retention of 96% over 1000 cycles at a 1C rate. This study emphasizes that the microstructure of the sulfide electrolyte is a critical factor influencing mechanically‐driven Li dendrite propagation in all‐solid‐state batteries. [ABSTRACT FROM AUTHOR]

Microstructural evolution of borosilicate glass–sulfate (BaSO4 or Na2SO4) mixture was observed in situ using a high‐temperature confocal scanning laser microscope. The phase compositions and sulfate retention of the mixture at different temperatures were also examined. The results indicate that for the glass–BaSO4 sample (abbreviated as BS), the borosilicate glass begins to melt at about 900°C, and the triangular BaSO4 crystals grow obviously between 900°C and 1100°C. At temperatures above 1100°C, the BaSO4 crystals gradually melt and decompose. For the glass–Na2SO4 sample (abbreviated as NS), strip‐shaped BaSO4 crystals begin to form at about 820°C after the borosilicate glass melting, and then gradually melt with further increasing temperature. When the temperature increases to 1000°C, the upper layer of the NS sample possesses Na2SO4, LiNaSO4, and BaSO4 phases, while the lower layer possesses an amorphous phase. Moreover, the SO3 retention in the BS sample remains almost unchanged with temperature increases from 900°C to 1100°C, and then decreases with further increasing temperature. The SO3 retention retained in the NS sample decreases rapidly at temperatures above 900°C. These findings can provide a guidance for vitrifying sulfur‐rich high‐level liquid waste. [ABSTRACT FROM AUTHOR]

Manufacturing of metal‐decorated carbon electrodes as a critical component of enzyme‐free glucose sensors has become an advanced strategy for fast and accurate glucose monitoring. By selectively irradiating the pre‐prepared chloroplatinic acid/polyimide (H2PtCl6/PI) precursor with photothermal energy, a creatively synchronized laser processing protocol is developed for assembling integrated three‐electrode system with platinum nanoparticle decorated laser‐induced graphene (PtNP‐LIG). In addition to the swift manufacturing of designable structures, laser power and raw‐material dosage are systematically explored as two key parameters to understand the process‐regulated microstructure and electro‐catalytic performance. Notably, by discovering the tuning mechanism for optimizing laser power‐dependent specific surface area of graphene backbone from 81.61 to 197.53 m2 g−1 and for enhancing H2PtCl6 concentration dependent Pt content from 0.75% to 4.16%, the sensitivity of PtNP‐LIG sensors to glucose oxidation has dramatically improved from 203.14 to 959.07 µA mM−1 cm−2, following closely the adjustable discipline of electrochemically active surface area (ECSA) from 37.75 to 104.19 mm2. Along with rapid response time, low limit of detection, and broad linear range, the proposed protocol is highly beneficial for designing and manufacturing next‐generation wearable human‐health related devices. [ABSTRACT FROM AUTHOR]

Ice has been suggested to have played a significant role in the origin of life partly owing to its ability to concentrate organic molecules and promote reaction efficiency. However, the techniques for studying organic molecules in ice are absorption‐based, which limits the sensitivity of measurements. Here we introduce an emission‐based method to study organic molecules in water ice: the phosphorescence displays high sensitivity depending on the hydration state of an organic salt probe, acridinium iodide (ADI). The designed ADI aqueous system exhibits phosphorescence that can be severely perturbed when the temperature is higher than 110 K at a concentration of the order of 10−5 M, indicating changes in hydration for ADI. Using the ADI phosphorescent probe, it is found that the microstructures of water ice, i.e., crystalline vs. glassy, can be strongly dictated by a trace amount (as low as 10−5 M) of water‐soluble organic molecules. Consistent with cryoSEM images and temperature‐dependent Raman spectral data, the ADI is dehydrated in more crystalline ice and hydrated in more glassy ice. The current investigation serves as a starting point for using more sensitive spectroscopic techniques for studying water‐organics interactions at a much lower concentration and wider temperature range. [ABSTRACT FROM AUTHOR]

2195 aluminum–lithium (Al–Li) and 2XXX series aluminum alloys are joined using resistance spot welding for the first time. The macrostructure, microstructure, element distribution, microhardness, and tensile‐shear property of spot‐welded joints are investigated. The microstructure of the fusion zone of 2195/2195, 2195/2219, and 2195/2A14 joints is fine equiaxed spherical grains. It is found that solute segregation of Cu occurs in the grain boundaries in the fusion zone, forming Al2Cu. The microhardness shows that due to the dissolution of strengthening phase T1, the hardness of the fusion zone of the three types of joints is lower than that of the base material. The 2195/2195 joint has the best mechanical performance among the three combinations, with maximum tensile‐shear force and absorbed energy reaching 16893.7 N and 24.9 J, respectively. The fracture surfaces of all three types of joints exhibit mixed ductile‐brittle characteristics. [ABSTRACT FROM AUTHOR]

Lead‐free polycrystalline manganese telluride holds great potential in the development of waste heat recovery due to its fascinating physical properties. However, the poor thermoelectric (TE) performance in the p‐type MnTe alloys always results from their inferior carrier concentration, leading to low power factor and high thermal conductivity which restrict the overall thermoelectric performance. In this work, the problem is solved by decoupling its electrical and thermal transports through the hole donor Ge‐deficiency in MnTe + x mol.% GeTe (0 ≤ x ≤ 4) compounds. Intrinsically, extra GeTe in MnTe + x mol.% GeTe compound offers free charge carriers due to a narrow bandgap comparatively, realizing not only a full assessment of stimulated electrical performance but also an enhanced power factor. Moreover, benefiting from the nano‐precipitates and tweed microstructures, the lattice thermal conductivity effectively reduces due to the intensive phonon scattering accordingly. Ultimately, a maximum ZT of ≈1.2 at 873 K in the 3 mol.% GeTe doped MnTe sample is realized. [ABSTRACT FROM AUTHOR]

In this work, the tungsten‐copper composites were fabricated by binder jet 3D printing technology. The effects of different printing layer thicknesses (50 μm to 100 μm) on the green density and green strength were investigated. Then, under the optimal layer thickness, the effects of different sintering temperatures (1300 °C to 1600 °C) on the microstructure and densification of tungsten‐40 wt.–% copper composites were studied. The experimental results showed that when the printing layer thickness was set as a lower value (50 μm), the tungsten‐40 wt.–% copper green part had the best strength and its density reached a maximum value of 60.73 %. After sintering for green parts printed with 50 μm layer thickness, the relative density, thermal conductivity and electrical conductivity of sintered parts first increased and then decreased with increasing sintering temperature. In our experiments, the tungsten‐40 wt.–% copper sample fabricated by binder jet 3D printing with a printing layer thickness of 50 μm under a sintering temperature of 1500 °C displayed the best properties, in which the relative density, thermal conductivity and electrical conductivity were 97.04 %, 228 W⋅m−1⋅K−1 and 46.5 % IACS, respectively. [ABSTRACT FROM AUTHOR]

Silicon carbide fiber‐reinforced SiC ceramic matrix composites (SiCf/SiC CMCs) based on a domestic KD‐SA SiC fiber were exposed to a wet oxygen atmosphere for 135 h at 800, 1100, and 1300°C. The evolution of the microstructure and mechanical properties of SiCf/SiC CMCs have been systematically investigated following oxidation. For weight change, CMC‐1300 showed the greatest gain (0.394%), followed by CMC‐1100 (0.356%) and CMC‐800 (0.149%). The volatilization of boron oxide (B2O3) combined with the slight oxidation of the SiC matrix at 800°C caused crack deflection and fiber pull‐out. The complete dissipation of the interphase could be found when the oxidation temperature increases to 1100°C, generated a fracture surface with brittle fracture characteristics. At 1300°C, crystalline SiO2 hindered oxygen diffusion, with evidence of fiber pull‐out. Based on thermodynamic calculations and microscopic observations, we propose a mechanism to explain the thermal degradation of SiCf/SiC CMCs. This work offers valuable guidance for the fabrication of SiCf/SiC CMCs that are suitable for high‐temperature applications. [ABSTRACT FROM AUTHOR]

Summary: Rice glutelin is poorly soluble which restricts its potential food application. Succinylation is a chemical modification that improves the solubility of proteins by derivatising the ɛ‐amino group of lysine residues. In this study, rice glutelin was modified by succinic anhydride at different succinic anhydride concentrations (10%, 20%, 30%, 40%, and 50%). The succinylated rice glutelin samples showed enhanced solubility, reduced particle size, and increased absolute zeta potential values. The emulsifying and foaming properties of succinylated rice glutelin were also significantly improved. Moreover, SEM revealed that the surface of succinylated rice glutelin had small pits and protrusions. These results suggest that succinylation can effectively improve the functional properties of rice glutelin, which will facilitate its application in the food industry. [ABSTRACT FROM AUTHOR]

The LaB6‐SiC composite with the different SiC content (0, 15, 30, 36, 50, 90, and 100 wt.%,) was densified by spark plasma sintering. The effects of SiC content on the densification behavior, microstructure, mechanical, and thermionic emission properties of LaB6‐SiC composite were systemically investigated. The results show that all the rapid shrinkage occurred at the heating stage during densification, and LaB6‐36 wt.%SiC composite owned the maximum shrinkage rate of 1.5 mm/min at T = 1798°C. The highest relative density of the composite decreased from 98.18% to 95.01% as the SiC content increased from 15 wt.% to 90 wt.%, under which the morphology of LaB6 grain evaluated from the equiaxed to elongated structure, and LaB6 grain size varied in the range of 5.05–11.42 μm. The similar eutectic structures were observed in the LaB6‐36 wt.% SiC composite because of some LaB6 grains melting. Both the highest fracture toughness of 5.15 ± 0.56 MPa.m1/2 and the highest bending strength of 313 ± 4.7 MPa belonged to the LaB6‐36 wt.% SiC composite, which also exhibited thermionic emission current density of 10.74 A/cm2 and work function of 2.99 eV at T = 1873 K. [ABSTRACT FROM AUTHOR]

In this article, the impacts of varying CeO2 contents and heat‐treatment procedures on the crystallization, microstructure, and dielectric characteristics of MgO–Al2O3–SiO2–TiO2–CeO2 (MASTC) materials are investigated. In this research, it is indicated that perrierite, rutile, and α‐cordierite are the major crystalline phases in the materials. An increased CeO2 content promotes the formation of perrierite and inhibits the precipitation of α‐cordierite and rutile in the glass ceramics. An appropriate amount of CeO2 content contributes to a dense microstructure and improves the dielectric characteristics of the samples. However, an excessive amount of CeO2 deteriorates the densification and dielectric characteristics of the MASTC materials. Furthermore, heat‐treatment temperature and duration also have a significant impact on the crystallization, microstructure, and dielectric performance of the materials. The MASTC material with 20.2 wt% CeO2, heat‐treated at 1100 °C for a duration of 3 h, possesses superior characteristics with a density of 3.14 g cm−3, a permittivity of 11.1, and a Q × f factor of 17 357 (14 GHz). [ABSTRACT FROM AUTHOR]

This research investigated the cutting performance of three different types of Si3N4‐based ceramic tools (Si3N4, Si3N4–SiCw, and Si3N4–SiCw–HfB2) with distinct mechanical properties during turning of ductile cast iron. Si3N4 ceramic tool, characterized by high hardness and low toughness, showed minor micro‐chipping and the highest average flank wear rate during the initial wear stage, leading to a short cutting life of 1679 m. Si3N4–SiCw ceramic tool, with low hardness and high toughness, exhibited the highest average flank wear rate during the middle and final wear stages, resulting a short cutting life (1602 m). In contrast, the Si3N4–SiCw–HfB2 ceramic tool, featuring high hardness and high toughness, demonstrated the lower average flank wear rate during all the wear stages, leading to a longest cutting life (2636 m). The results indicated that the average flank wear rate during the initial wear stage was mainly influenced by toughness, while during the middle and final wear stages, the average flank wear rate was primarily dependent on hardness. [ABSTRACT FROM AUTHOR]

The desired clinical bone prostheses should achieve satisfactory interface integration and osteoinduction, as well as good surgical convenience. Here, a highly malleable 3D printed prosthesis with compressive strength at 13 MPa is constructed by dopamine, polyvinyl alcohol, and micro‐sized hydroxyapatite (86 wt%) as composite bioinks, which is endowed with good plasticity and can quickly match irregular defects by easily trimming. Spatially decorated collagen and hyaluronan greatly enriched the hierarchical microstructure and biological activity of malleable prosthesis. This prosthesis accelerates the proliferation and osteogenic differentiation of stem cells, regulates M2 polarization of macrophage, and promotes endogenous stem cell recruitment and early angiogenesis. Meanwhile, it significantly reinforces biomineralized deposition and vascularization, reaches full coverage of new bone in the rabbit cranial defect after 15 weeks (Φ = 10 mm), and achieves well osseointegration capacity with interfacial binding strength at 71.2% of the natural skull. This osteoinductive prosthesis provides a new design idea for bone filling. [ABSTRACT FROM AUTHOR]

Vacuum brazing of Ti-47Al-2Nb-2Cr-0.15B (at%) alloy with TiH2-Ni-TiB2 powder filler in situ assisted 20 vol% TiB whiskers is performed at 1190-1250 °C for 10 min. The microstructure evolution of the joint at various brazing temperatures and the relationship between microstructure and joint properties are systematically investigated. In the results, it is indicated that the interfacial microstructure of the γ-TiAl joint brazed at 1230 °C is γ-TiAl/Ti3Alþ Al3NiTi2 (layer I)/Al3NiTi2þ Ti3Al (layer II)/Al3NiTi2þ TiBþ Ti3Al (layer III)/Al3NiTi2þ Ti3Al (layer II)/Ti3Alþ Al3NiTi2 (layer I)/γ-TiAl. The layer II containing high-hardness Al3NiTi2 is always the weakest part in the brazed joint. The microstructure refinement and load-bearing behavior of layer III are increased with brazing temperature due to the increasing length of the TiB whisker. Variation of the content of low-hardness Ti3Al in layer II as well as its microstructure refinement and internal bonding strength, the shear strength of γ-TiAl joints is first increased and then decreased with brazing temperature, but that of Al3NiTi2 in layer II is reversed. The joint brazed at 1230 °C possesses the maximum shear strength of 332.87MPa and a quasi-cleavage fracture occurs in the layer II mainly consisted of Al3NiTi2. [ABSTRACT FROM AUTHOR]

The present study focuses on the synthesis of three distinct WC‐HEA hard alloys using the SPS method, using three different grades of tungsten carbide with varying particle sizes. Subsequently, an investigation is conducted to analyze the influence of WC particle size on the microstructure and properties of WC‐10CoCrFeNiAl hard alloys. Additionally, an investigation was conducted to assess the influence of small particle size WC addition content on both the microstructure and properties of this advanced alloy. The results indicate that a reduction in the particle size of WC leads to an increase in hardness, while exhibiting a nonmonotonic change in fracture toughness of WC‐10CoCrFeNiAl hard alloy. The presence of smaller WC particles promotes the formation of N7C3 and η phase (M3W9C4), which compromises its toughness while simultaneously enhancing its hardness. The mechanical properties are optimized when the particle size of WC is ≈1 μm. The incorporation of fine WC particles significantly enhances hardness while compromising fracture toughness. When the content of small particle WC reaches 25 wt%, the mechanical properties of the dual‐scale hard alloy are optimized, the hardness and fracture toughness are 18.8 GPa and 11.1 MPa.m1/2, respectively. [ABSTRACT FROM AUTHOR]

In this study, we investigated the cutting performance and wear mechanisms of Ti(C,N)‐based cutting tools containing varying weight percentages (0%, 5%, 10%, and 15%) of high‐entropy carbide (HEC) (V0.2Nb0.2 Mo0.2Ta0.2W0.2)C phase, when used for turning nodular cast iron. According to the turning test results, the cermet cutting tools containing 0 wt%, 5 wt%, 10 wt%, and 15 wt% HEC phases demonstrated effective cutting lives of 402, 720, 632, and 465 s, respectively. The tool with 5 wt% HEC phase showed the best cutting performance. When cutting nodular cast iron with cermet cutting tools, the main wear mechanisms observed were diffusion, oxidation, adhesion, and abrasion on the flank surface, along with diffusion, oxidation, and abrasion on the rake surface. The results of this study indicated that (V0.2Nb0.2Mo0.2Ta0.2W0.2)C could be adopted as an effective reinforced phase in the cermet cutting tools. [ABSTRACT FROM AUTHOR]

Ti15Mo alloy has been regarded as one of the most potential biomedical materials due to its excellent performance. However, the low hardness and poor wear resistance of titanium alloy limit the further application. Therefore, high temperature solid carburising technology was performed on the surface of Ti15Mo alloys to prepare titanium carbide (TiC) coating with graphene (G) as the carburising agent. The microstructure, mechanical properties, and tribological properties of TiC coating under different lubricants were investigated. Results showed that TiC coating was closely bonded to the titanium substrate. The maximum thickness of TiC coating treated with 1150°C was approximately 184.02 μm, and the microhardness of alloys treated with 1100°C can achieve 1221.5 HV. All modified Ti15Mo alloys showed improved tribological performance compared to the original samples. The wear mechanisms of modified Ti15Mo alloys were abrasive wear and adhesive wear under the SBF lubricant, and the TiC coating was slightly peeled off. The overall friction coefficient and wear rate under 25% calf serum lubricant were lower than the SBF lubricant, and surface scratches were almost absent, and slight abrasive wear and adhesive wear occurred on the surface. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, there has been an increasing demand for plant‐based cheese analogues, however, the protein content of plant‐based cheeses currently on the market is generally low and cannot meet the nutritional needs of consumers. RESULTS: Based on the ideal value similarity method (TOPSIS) analysis the best recipe for plant‐based cheese was 15% tapioca starch, 20% soy protein isolate, 7% gelatine as a quality enhancer and 15% coconut oil. The protein content of this plant‐based cheese was170.1 g kg−1, which was close to commercial dairy‐based cheese and significantly higher than commercial plant‐based cheese, The fat content was 114.7 g kg−1, lower than that of commercial dairy‐based cheese. The rheology properties show that the viscoelasticity of the plant‐based cheese is higher than that of dairy‐based cheese and commercial plant‐based. The microstructure results show that the type and content of protein has a significant impact on its microstructure. The Fourier‐transform infrared (FTIR) spectrum of the microstructure shows a characteristic value at 1700 cm−1, because the starch was heated and leached to form a complex with lauric acid under the action of hydrogen bond. It can be inferred that in the interaction between plant‐based cheese raw materials, fatty acids serve as a bridge between starch and protein. COUCLUSION: This study described the formula of plant‐based cheese and the interaction mechanism between the ingredients, providing a basis for the development of subsequent plant‐based cheese related products. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Aluminum oxynitride (AlON) ceramics doped with different sintering aids were synthesized by spark plasma sintering process. The microstructures, mechanical, and optical properties of the ceramics were investigated. The results indicate that the optimal amount of sintering aids is 0.06 wt% La2O3 + 0.16 wt% Y2O3 + 0.30 wt% MgO. The addition of La3+ and Mg2+ decreases the rate of grain boundary migration in ceramics, promotes pore elimination, and inhibits grain growth. The addition of Y3+ facilitates liquid‐phase sintering of AlON ceramics. Moreover, the addition of Mg2+ effectively promotes twin formation in the ceramics, which hinders crack propagation and dislocation motion when the ceramics are loaded. Hence, the AlON ceramic doped with 0.06 wt% La2O3 + 0.16 wt% Y2O3 + 0.30 wt% MgO exhibits a relative density of 99.95%, an average grain size of 9.42 μm, and a twin boundary content of 10.3%, which contributes to its excellent mechanical and optical properties. [ABSTRACT FROM AUTHOR]

Herein, a spectrum of electric field–induced microstructural evolution phenomena are observed in polycrystalline Bi2O3‐doped ZnO, and the underlying mechanisms are revealed. An applied electric field can drive the migration of bismuth (Bi) toward the negative electrode (including the motion of the charge‐neutral Bi‐rich liquid phase via electrochemical coupling), which produces a Bi‐free zone near the anode. The field‐induced migration of Bi creates a junction between electron‐conducting ZnO and ion‐conducting Bi2O3‐doped ZnO (via Bi2O3‐enriched liquid‐like intergranular films [IGFs]), where an oxygen ion current is converted to an electron current while generating O2 gas, generating a porosity belt. Aberration‐corrected electron microscopy further reveals the formation of three distinct types of grain boundaries (GBs). "Clean" ZnO GBs are observed near the anode, where Bi is depleted by the electric field. Bi2O3‐enriched liquid‐like IGFs (disordered GBs) are observed in the middle section. Near the cathode, electrochemical reduction induces an GB disorder–order transition to form fast‐moving Bi2O3‐enriched ordered GBs, which causes abnormal grain growth. Herein, several new field–matter interaction phenomena are discovered and an exemplar of field effects on microstructural evolution are established at multiple length scales in the presence of GB complexion (phase‐like) transitions. [ABSTRACT FROM AUTHOR]

Small‐module gear is the key basic component of equipment in the fields of aerospace, weapon equipment, communication, and so on, which is an important embodiment of the high‐end intelligent equipment manufacturing level. Herein, the small‐module gears are fabricated by micro‐metal injection molding (micro‐MIM) and the microstructure and mechanical properties of the gears are characterized. The small‐module gears are successfully molded, debounded, and sintered based on the feedstock with 58% powder loading. The structure and mechanical properties of the samples are investigated in relation to the sintering temperature for the determination of optimum sintering conditions. The results show that the relative density and average grain size increase with the increment of sintering temperature, and the maximum relative density of 97.6% is obtained at the sintering temperature of 1320 °C. The tensile strength and hardness of the sintered sample are 2034 MPa and 709 HV at 1320 °C, respectively, presenting the most desirable mechanical properties, which are attributed to the formation of martensite with high strength and hardness at the expense of pearlite and ferrite and the alloy carbide precipitations in the microstructure. Herein, important guidance to develop low‐cost and high‐performance small‐module gear is provided by using micro‐MIM. [ABSTRACT FROM AUTHOR]

Poor interfacial contacts of Li mental/solid‐state electrolytes (SSEs) cause high impedance and induce lithium dendrite growth, which hinders the practical viability of solid‐state batteries (SSBs). Optimizing the surface chemistry of SSEs has been widely adopted for improving the Li/SSE interfacial contact. Their surface's microstructure, another critical factor influencing the actual performance of SSBs, however, has seldom been paid attention to; and the corresponding mechanism remains unclear. Addressing this issue, the authors herein propose a "surface microstructure optimization" strategy that can significantly enhance the Li/SSE interfacial contact, and in the meantime, quantify the correlations between SSB's performance and SSE's surface roughness regarding the interfacial resistance, current focusing, critical current density (CCD), and lithium deposition. Based on these fundamental understandings, a low‐surface‐roughness SSE is developed, which shows extremely small interfacial impedance (1.7 Ω cm2) and ultra‐long stable cycling life (4500 h at 0.2 mA cm−2). This work not only comprehensively demonstrates the fundamental relationship between the surface microstructure of SSEs and their battery performance but also presents a new insight into the modulation of surface kinetics of ceramic SSEs toward achieving dendrite‐free SSBs. [ABSTRACT FROM AUTHOR]

Nanoscale recombination between carbon nanomaterials (CNs) and polymers has been proposed for a variety of industrial and scientific applications. Composite energetic materials consisting of CNs with novel laser ignition property and tunable combustion performance have attracted people's attention. Here, reported is the novel manufacturing process of uniform nitrocellulose (NC)/graphene oxide (GO) nanocomposite propellant and the micro‐structure, laser ignition and isovolumetric burning features of the propellants introduced by GO. The results of microstructure tests indicated that GO (0.25–2 wt%) was stripped and dispersed homogeneously and dense nanocomposite propellants were prepared successfully through water ultrasonic dispersion, twin‐screw mixture, as well as compression molding. The crystallization of NC was forbidden by doping GO, meanwhile, the thermal stability and thermal conductivity of the composite propellants increased slightly with the addition of GO. The results of laser ignition combustion experiments showed that GO was an efficient additive to shorten the ignition delay time from more than 2000–14 ms when 2 wt% of GO was doped, however, the combustion flame intensity was also weakened due to the addition of GO. The combustion tests in a closed bomb vessel were conducted, and the results showed that GO would not affect the stable combustion of NC at high combustion pressure, moreover, the burning rate and dynamic vivacity of the composite propellants decreased with the increase of GO content. [ABSTRACT FROM AUTHOR]

DP780 steels and 6061‐T6 aluminum alloys are joined using the resistance element welding (REW) process with a flat Q235 rivet. The macrostructure, microstructure, and mechanical properties of the REW joints are investigated. The nugget zone and upper‐critical heat‐affected zone (UGHAZ) microstructure exhibit lath martensite. The inter‐critical heat‐affected zone (ICHAZ) microstructure consists of ferrite and martensite. Two types of intermetallic compound (IMC) layers are formed at the steel/Al interface. A tongue‐like Fe2Al5 layer is found adjacent to the steel side, while a needle‐like Fe4Al13 layer is found adjacent to the aluminum alloy side. The welding current has a significant influence on the nugget size, peak load, and energy absorption of joints. The fracture behavior analysis of the REW joints is performed using the in situ digital image correlation (DIC) method. There are two failure modes of the REW joint under different welding currents: pull‐out failure (POF) and the base material pull‐out failure (BPF). At a welding current of 17 kA, the maximum tensile‐shear value of the REW joints is 6.27 kN with a nugget diameter of 5.37 mm. The failure mode of the REW joints is mainly BPF mode that exhibits superior lap‐shear performance. [ABSTRACT FROM AUTHOR]

The combination of electric and magnetic field assisted freezing has potential as a new means of improving the freeze–thaw quality of green peppers. In this work, the quality of the freeze–thawed product was assessed in terms of thawing juice loss, moisture profile, ascorbic acid content, antioxidant activity, flavor, and microstructure. Juice loss was reduced by 16%–68%, freezing time was shortened by 15%–26%, and the nutrient retention rate was higher in the physical field‐assisted case compared to the no‐physical field case. Interestingly, the combined freezing of the two physical fields showed better freezing results compared to a single electric or magnetic field, with juice loss reduced to 3.04%, retention of 82% of calcium ions, retention of ascorbic acid increased by 6%–15%. In addition, the content of hexenal and methyl salicylate and other aromatic substances increased, showing a good flavor quality such as increased umami. The results suggest that combined electric and magnetic field assisted freezing is better in improving the quality of frozen products and may be a potential alternative to freezing and thawing of fruits and vegetables. Practical application: This research provides a simple and novel method for improving the speed and quality of frozen products. These steps combine electric and magnetic fields to explore, improve the quality of frozen products, but also provide a new idea for freezing research. [ABSTRACT FROM AUTHOR]

In this paper, indium oxide (In2O3) nanomaterials are successfully synthesized on the silicon substrates by hydrothermal method and calcination. By changing the ratio of raw materials, In2O3 exhibits three morphologies of nanorods, nanomaces, and nanorod‐flowers. Among the three morphologies of In2O3 nanomaterials, the nanorod‐flowers shaped In2O3 shows a strong field emission property, the turn‐on electric field as low as 0.97 V/µm and the field enhancement factor β up to 1053. The excellent performance is attributed to the higher length to diameter (L/D) ratio of the emitting tips and the better crystal quality for nanorod‐flowers shaped In2O3. The authors also show that for the nanorod‐flowers shaped In2O3, increasing separation distance, the turn‐on electric field increases up to about 3.67 V/µm and β decreases to 573 at d = 900 µm. This work provides new insights to design and synthesize nanomaterials with excellent field emission properties. [ABSTRACT FROM AUTHOR]

Multicomponent transition metal boride composite–sintered bodies were prepared by spark plasma sintering, and the composite sintered bodies prepared at different sintering temperatures (1500–1900°C) were characterized. The experimental results showed that several other compounds diffused into the TiBx phase at lower sintering temperatures under the combined effect of temperature and pressure due to the nonstoichiometric ratio of TiB1.5 vacancies. When the temperature reached 1900°C, only the hexagonal phase remained. With the continuous increase of sintering temperature, the Vickers hardness and fracture toughness of the sintered bodies had a trend of increasing first and then decreasing, due to the continuous reduction of the porosity of the cross section of the sintered bodies and the growth of the grain size. The Vickers hardness and fracture toughness of sintered body obtained at 1800°C are the best, which are 24.4 ± 1.8 GPa and 5.9 ± 0.2 MPa m1/2. At 1900°C, the sintered body was a single‐phase hexagonal high‐entropy diboride. Its Vickers hardness and fracture toughness were 21.9 ± 1.5 GPa and 5.4 ± 0.2 MPa m1/2, respectively; it showed a clear downward trend. [ABSTRACT FROM AUTHOR]

In this study, a novel high‐entropy carbide‐based ceramic cutting tool was developed. The cutting performance of three kinds of high‐entropy carbide‐based ceramic tools with different mechanical properties for the ISO C45E4 steel were evaluated. Although the pure (Ti0.2Zr0.2Nb0.2Ta0.2Mo0.2)C0.8 ceramic cutting tool exhibited the highest hardness of 25.06 ± 0.32 GPa, the cutting performance was poor due to the chipping and catastrophic failure caused by the low toughness (2.25 ± 0.27 MPa m1/2). The (Ti0.2Zr0.2Nb0.2Ta0.2Mo0.2)C0.8–15 vol% cobalt cutting tool with highest fracture toughness (6.37 ± 0.24 MPa m1/2) and lowest hardness (17.29 ± 0.79 GPa) showed the medium cutting performance due to the low wear resistance caused by the low hardness. The (Ti0.2Zr0.2Nb0.2Ta0.2Mo0.2)C0.8–7.7 vol% cobalt cutting tool showed the longest effective cutting life of ∼67 min due to the high wear resistance and chipping resistance caused by the high hardness (21.05 ± 0.72 GPa), high toughness (5.35 ± 0.51 MPa m1/2), and fine grain size (0.60 ± 0.15 μm). The wear mechanisms of the cobalt‐containing (Ti0.2Zr0.2Nb0.2Ta0.2Mo0.2)C0.8 ceramic cutting tools included adhesive wear and abrasive wear and oxidative wear. This research indicated that the high‐entropy carbide‐based ceramics with high hardness and high toughness have potential use in the field of cutting tool application. [ABSTRACT FROM AUTHOR]

A medium‐carbon steel was treated by the bainitic isothermal transformation plus quenching and partitioning (B‐QP) process to obtain bainite/martensite/retained austenite multiphase microstructure, and its fatigue crack propagation (FCP) behavior was evaluated in contrast with BAT (bainite austempering) sample with fully bainite microstructure. Results show that B‐QP sample exhibits a lower FCP rate and higher fatigue threshold ΔKth (12.6 MPa·m1/2). Moreover, the FCP path of B‐QP sample displays a strongly tortuosity and more crack branching due to more filmy retained austenite (7.2%) and higher percentage of high angle misoriented boundaries (68%). The larger crack tortuosity and the secondary cracks as result of crack branching are primarily responsible for the lower FCP rate of B‐QP sample. In addition, the FCP rate curve of B‐QP sample shows a pronounced small plateauing at the near‐threshold zone, which can be ascribed to the mechanical twinning that occurred in the filmy retained austenite. Highlights: The B‐QP sample exhibits a lower FCP rate and higher fatigue threshold.The crack tortuosity and secondary cracks are the mainly reasons for the lower FCP rate.The B‐QP sample shows a pronounced small plateauing caused by the mechanical twinning. [ABSTRACT FROM AUTHOR]

The cruciform welded joint is a weak position of filter press to cause fatigue failure under cyclic conditions. In this study, cavitation jet peening (CJP) treatment is proposed to improve the fatigue life of SAF2205 cruciform welded joints. The effects of different CJP treatment positions on the residual stress, microstructure, and microhardness were studied. The results show that different CJP treatment positions have different on residual stresses and fatigue life. The order of the residual stress in fracture position from large to small is the fully treated specimen, untreated specimen, one‐sided treated specimen, and diagonal treated specimen, which is exactly opposite to the order of fatigue life from large to small. After the diagonal CJP treatment, the fatigue life is increased by up to 242.19%, and the residual stress at the weld toe is reduced by more than 80%. A strengthening layer with thicknesses of about 400 μm is formed. [ABSTRACT FROM AUTHOR]

Glasses cooled from impact melt and vapor are a common component in lunar regolith, carrying important information about protolith composition, regolith formation, and impact flux on the Moon. Interpretations, however, are frequently challenged due to widespread ambiguity in determining their provenances. Regolith samples returned by China's Chang'E‐5 mission provide a unique opportunity to study the microscopic mechanism of regolith reworking on the Moon, because as evidenced by the coherent radioisotope ages and petrographic characteristics of basaltic clasts in the regolith, the Chang'E‐5 regolith was mainly evolved from local mare materials, containing minor exotic components. Here, we report 153 glass particles larger than 20 μm in diameters that were screened from 500 mg of Chang'E‐5 regolith. Most glass particles have rotational shapes and contain structural and/or compositional heterogeneities in interiors, and geochemical analyses reveal a dominant origin as impact melt of local mare materials. Surfaces of the impact glasses are observed to have abundant protruded and dented microstructures, which are classified as different groups based on their morphology and geochemistry. Similar microstructures were observed on impact spherules collected by the Apollo and Luna missions, but those on the Chang'E‐5 impact glasses were formed without substantial involvement of exotic ejecta. Microstructures such as silicate melt pancakes that frequently exhibit flow spikes at margins, nano‐phase iron‐rich mounds that are arranged with semi‐equidistant spaces in curves and patches, spatially clustered microcraters that are indicative of secondary impacts, and blunt linear scratches with terminal particles all suggest that regolith reworking mainly occurred among local materials at low speeds. Plain Language Summary: Regolith particles on the Moon exhibit an abundance of small‐scale surface texture or microstructures that were formed during regolith reworking. Lunar impact glasses are mainly melted from surface regolith, and microstructures on their surfaces record the history of subsequent regolith reworking. The possible contribution of exotic ejecta in regolith gardening is an interesting topic in lunar science. However, resolving this issue has been a persistent difficulty by both remote observations and sample analyses. China's Chang'E‐5 mission returned regolith samples from one of the youngest mare units on the Moon, and earlier sample analyses revealed little exotic components. In 500 mg of Chang'E‐5 regolith, we handpicked 153 glass particles that are larger than 20 μm. Most of the particles are heterogeneous impact glasses that contain voids and unmelted fragments, and geochemical analyses showed that the remaining structurally homogeneous particles were also impact glasses formed from local regolith. Based on high‐resolution microscopic imaging and elemental mapping, we recognized and classified the abundant protruded and dented microstructures on the glass particles. Morphology and crosscutting relationship of the microstructures suggest that they were mostly formed during regolith reworking by low‐speed events of local materials that had various thermophysical states (vapor, melt, and solid). Key Points: 153 glass particles larger than 20 μm in diameters are separated from 500 mg of Chang'E‐5 regolithCrosscutting relationships among surface microstructures reveal intricate regolith reworking processesProtruded and dented microstructures on surfaces of Chang'E‐5 glass particles were formed with velocities lower than primary impacts [ABSTRACT FROM AUTHOR]

Combining DSC/TG–QMS analysis and dilatometry experiments at constant heating rates, the sintering behaviors of the Ti(C,N)‐based cermets with carbon additives were studied. It is found that the additives of diamond or graphite could promote the interactions among raw powders during solid‐state sintering. The outgassing behavior and endothermic effect were enhanced, thereby resulting in the increasing densification activation energy. The negative activation energy during the liquid phase sintering indicates that the dissolution–precipitation process occurs easily and provides a rapid densification path. The dissolution–precipitation process for cermets with.6‐wt% graphite or.6‐wt% diamond additive became more efficient than for cermets without additional carbon additive. The white‐core/gray‐rim grains were clustered together in the cermets with.6‐wt% graphite additive, whereas they were distributed evenly in the cermets with.6‐wt% diamond additive. Moreover, the average sizes of ceramic grains in the cermets without additional carbon additive, and with.6‐wt% graphite or.6‐wt% diamond additives, were.453, and.517, or.525 μm, respectively. [ABSTRACT FROM AUTHOR]

Lithium aluminosilicate glass-ceramics are well known for good transparency, high fracture toughness, low thermal expansion, and good ion exchange ability. In this study, new transparent Li2O-Al2O3-SiO2 (LAS) glass-ceramics with petalite and β-spodumene solid solution as the major crystalline phases were invented for favorable mechanical properties and potential for application in the hollowware, tableware, container, and plate glass industries. Crystal phases are mainly influenced by the ratio of Al2O3 to SiO2 concentrations. The concentration of SiO2 required to form specific crystalline phases in the glass-ceramics is higher than that inferred from the ternary phase diagram. Al2O3 content is required to be sufficiently high for the formation of crystals, instead of balancing excess amounts of Li2O in the glass. The average transmittances of 2.0 ± 0.1 mm thickness samples in visible light regions (400–700 nm) can reach more than 80% with crystal sizes of 20–40 nm. Transmittance is significantly decreased for heat treatments around 710◦C, due to the high growth rate of β-spodumene solid solution crystals. Vickers hardness, indentation toughness, and crack probabilities of transparent LAS glass-ceramics are significantly improved compared with standard soda lime silicate glass, due to the crack bridging and deflection of crystal grains. [ABSTRACT FROM AUTHOR]

Although it has been proven that porous, heteroatomic, and defective structures improve Na storage performance, they also severely affect the initial Coulombic efficiency (ICE) due to the huge irreversible capacity in the first cycle, which always limits the practical application of carbon anodes in commercial Na‐ion batteries (NIBs). Here, we show the successful synthesis of nanocrystalline cellulose and the derivative hard carbons. A series of treatments including acid hydrolysis, hydrothermal carbonization, and high‐temperature pyrolysis help tune the pores, heteroatoms, and defects to achieve an optimized balance between superior ICE and reversible capacity of up to 90.4% and 314 mAh g−1. This study highlights that tailoring the electrode microstructure could be an important strategy in the future design of carbonaceous anode materials for high‐performance Na‐ion batteries. [ABSTRACT FROM AUTHOR]

Human neuroimaging studies have demonstrated that exercise influences the cortical structural plasticity as indexed by gray or white matter volume. It remains elusive, however, whether exercise affects cortical changes at the finer‐grained myelination structure level. To answer this question, we scanned 28 elite golf players in comparison with control participants, using a novel neuroimaging technique—quantitative magnetic resonance imaging (qMRI). The data showed myeloarchitectonic plasticity in the left temporal pole of the golf players: the microstructure of this brain region of the golf players was better proliferated than that of control participants. In addition, this myeloarchitectonic plasticity was positively related to golfing proficiency. Our study has manifested that myeloarchitectonic plasticity could be induced by exercise, and thus, shed light on the potential benefits of exercise on brain health and cognitive enhancement. [ABSTRACT FROM AUTHOR]

The hot deformation behavior of Incoloy825 alloy is investigated by isothermal compression test at the temperature range of 950–1150 °C with strain rates of 0.001–10 s−1. The dynamic recrystallization (DRX) mechanism in the transition zone is subdivided and clearly revealed. The results show that the instability domain is mainly located in the low temperature with high strain rate region (950–1050 °C, 1–10 s−1). The feasible domain can be divided into two parts: the first is located in the temperature range of 1000–1150 °C with a strain rate of 0.001 s−1, the second is located in strain rate of 0.01–1 s−1 at 1150 °C, and the optimum processing parameters is the temperature of 1150 °C with a strain rate of 1 s−1. A transition zone of the DRX mechanism appears during hot deformation, in which three DRX mechanisms occur, discontinuous dynamic recrystallization (DDRX) mechanism, continuous dynamic recrystallization mechanism (CDRX), and twin dynamic recrystallization (TDRX) mechanism. The formation of a DRX grain is the comprehensive effect of multiple mechanisms, which can promote and transform each other. Each mechanism contributes a different role. [ABSTRACT FROM AUTHOR]

Dietary chia seed (Salvia hispanica L.) has significant health‐related benefits due to its high nutrient contents. However, few studies reported the fate of whole seeds in the gastrointestinal tract. Herein, we explored the digestive characteristics in terms of hydrolysis of nutrients, structural and functional properties with a static in vitro digestion method. After gastrointestinal digestion, the digestibility of lipid and protein was 0.46% and 11.38%, respectively. The release rates of tryptophan, tyrosine and lysine were greater than 20%, whereas the glutamic acid and aspartic acid were less than 5%. The microscopic results (optical microscopy (OM), laser scanning confocal microscopy (LSCM) and scanning electron microscopy (SEM)) demonstrated that the seeds remained intact, and the mucilage adhered tightly to the seed coat during digestion. The water holding capacity and oil holding capacity of seeds accounted for 6.37 and 3.28 g/g after intestinal digestion, which were significantly lower than gastric digestion endpoints (P < 0.05). And there were no significant differences in Fourier transform infrared spectroscopy of G‐Mucilage and I‐Mucilage. In general, preprocessing before being consumed is necessary for chia seeds to take full advantage of rich polyunsaturated fatty acids and proteins. [ABSTRACT FROM AUTHOR]

Herein, influences of air‐cooling, water‐cooling, and liquid nitrogen‐cooling (LN‐cooling) on microstructures and mechanical properties of Sn–58Bi alloy are studied. It is observed that nearly complete eutectic structures are obtained in air‐cooled Sn–58Bi alloy. Fine grains and many low‐angle grain boundaries (LAGBs) are obtained in water‐cooled Sn–58Bi alloy. The LN‐cooling method causes Bi atoms to form large, regular rectangular shapes, and there are many high‐angle grain boundaries (HAGBs) distributed inside the specimen. Impact tests are performed at room temperature. When the impact rate is 0.98 m s−1, the fracture energy of the water‐cooled Sn–58Bi alloy peaks to 71.5 mJ. The fracture of the LN‐cooled impact specimen has a large cleavage step due to the interaction of cleavage cracks and the HAGBs. These experimental results lay the relevant theoretical foundation for the practical application of Sn–58Bi solder alloys. [ABSTRACT FROM AUTHOR]

Graphite/copper joints are prepared by brazing with Cu‐50TiH2 filler. The influence of the interfacial structure on the microstructure and mechanical properties of graphite/copper joints is investigated. Straight and zigzag interfacial configurations are designed. The microstructure and compositions on the brazing interface are observed and analyzed, and the shear strength of the joints is evaluated. The interfacial morphologies show a good metallurgical combination with no apparent defects. The interfacial transition layer mainly consists of a Cu‐based solid solution, Ti‐Cu intermetallic compound, and small amounts of TiC near the graphite substrate. The widths of the transition layer are ≈25–50 and 490 μm, respectively, for straight and zigzag interfacial configurations. There is a high hardness region that corresponds to the transition layer close to the graphite matrix. The shear strength of the joint with a zigzag structure interface can reach 17.9 MPa, which increases by 2.75 times compared to that of the straight interface. The zigzag structure between the graphite and the transition layer effectively improves the joint strength due to the increases in the bonding area and deflection of the fracture path. [ABSTRACT FROM AUTHOR]

Hydrogels have become the material of choice in bioelectronic devices because their high‐water content leads to efficient ion transport and a conformal interface with biological tissue. While the morphology of hydrogels has been thoroughly studied, systematical studies on their ionic conductivity are less common. Here, an easy‐to‐implement strategy is presented to characterize the ionic conductivity of a series of polyelectrolyte hydrogels with different amounts of monomer and crosslinker and correlate their ionic conductivity with microstructure. Higher monomer increases the ionic conductivity of the polyelectrolyte hydrogel due to the increased charge carrier density, but also leads to excessive swelling that may cause device failure upon integration with bioelectronic devices. Increasing the amount of crosslinker can reduce the swelling ratio by increasing the crosslinking density and reducing the mesh size of the hydrogel, which cuts down the ionic conductivity. Further investigation on the porosity and tortuosity of the swollen hydrogels correlates the microstructure with the ionic conductivity. These results are generalizable for various polyelectrolyte hydrogel systems with other ions as the charge carrier and provide facile guidance to design polyelectrolyte hydrogel with desired ionic conductivity and microstructure for applications in bioelectronic devices. [ABSTRACT FROM AUTHOR]

Stimulated by the requirement for wearable electronics, crack‐based strain sensors made from polymer‐supported metal films have been reported as a prospective structure for detecting subtle deformation with ultrahigh sensitivity and excellent flexibility. However, the regulation of crack preparation remains a challenge and the use of noble metals retards the large‐scale promotion toward practical application. Here, a cost‐effective strain sensor with ultrahigh strain sensitivity under small strains (ε) is designed based on the submicron to nanoscale voided clusters in Cu‐Al alloy films. The formation of channel cracks in the film is manipulated by regulating the intrinsic microstructure of the film, and the corresponding mechanism is discussed in detail. The strain sensor developed from the cracked Cu‐Al film exhibits ultrahigh gauge factors as high as 584 (0% < ε < 0.5%), 10219 (0.5% < ε < 0.9%), 43152 (0.9% < ε < 1.75%) which is among the highest in reported values. Furthermore, the practical application of the developed sensor in wearable electronics and detection of small deformation is demonstrated. This work provides a novel approach to optimize the sensing performance of flexible strain sensors. [ABSTRACT FROM AUTHOR]

The conflict between high sensitivity and wide sensing range greatly limits the extensive application of flexible pressure sensors. To produce a sensor with both high sensitivity and wide range is still a challenging work. Herein, flexible and highly sensitive piezoresistive sensors with wide sensing range are developed by combining the alkali‐treated 3D crinkled MXene with microstructured polydimethylsiloxane (PDMS). Sensors with different‐roughness PDMS films as flexible substrate and the unprocessed MXene as the conductive material are prepared to clarify the geometric design for the ultra‐wide pressure range (0–800 kPa). Then, other sensors assembled by NaOH‐alkalized 3D crinkled MXenes and rough PDMS are fabricated to illustrate that the material optimization can further enhance the sensitivity (up to 1104.38 kPa−1). The sensor shows a low limit of detection (17 Pa), fast response time (100 ms), good cycle stability (3000 cycles, 300 kPa), and can detect over a wide pressure range from that of the tiny pills, pulse, heartbeat, throat vibration, and the change of water weight, exhibiting a broad prospect in health monitoring systems and human‐machine interaction. [ABSTRACT FROM AUTHOR]

The safe treatment of radioactive‐contaminated soil is of great significance. In this work, neodymium‐contaminated soil was successfully immobilized using microwave sintering to form glass‐ceramics. The microstructure, morphology, elemental distribution, Vickers hardness, and chemical durability of the sintered samples were analyzed. The results showed that the glass‐ceramic is more suitable to immobilize the waste compared with the glass matrix. XRD and SEM‐EDS results proved that the waste form has been totally immobilized in the sintered matrix whether in glass‐ceramics and glass. However, the leaching rate of element Nd in glass‐ceramic was lower than the glass matrix at 28 d. Moreover, the Vickers hardness results of glass‐ceramic were higher than that of glass. Thus, glass‐ceramics can not only reduce sintering temperature and save energy but also achieve a better immobilizing effect. Our investigation reflects that glass‐ceramics are more suitable for neodymium‐contaminated soil immobilization using the microwave sintering method. [ABSTRACT FROM AUTHOR]

Of late, wire arc additive manufacturing (WAAM) is extensively used in the aerospace and automotive fields to produce large complex metallic components. The water‐bath method is applied for active cooling to address the heat accumulation problem in WAAM. Herein, the modified water‐bath method with a changing level is used to realize different phase transformations, and the microstructure and mechanical properties of the sample are investigated. Heat accumulation in the sample is eliminated using the modified water‐bath method. Furthermore, the microstructure of the fabricated sample shows a mixture of polygonal ferrite (PF), upper bainite (UB), and lath bainite (LB). Layer bands are formed in the entire sample, except in the final layer, and equiaxed ferrite (EF) and an increased fraction of PF appear in these zones. The microhardness and tensile property are enhanced due to the fine LB. The considerable difference in the microhardness between LB and PF causes an obvious wave of hardness, and the tensile property along the horizontal direction is better than the vertical. This study is expected to help broaden the application of the water bath in the microstructure control. [ABSTRACT FROM AUTHOR]

Summary: In this study, the effect of high‐pressure processing (HPP) on the physico‐chemical properties and microstructure of prepared chicken breast meat products was investigated. The result showed that the pH and TBARS values of the prepared chicken breast gradually increased, while the total volatile basic nitrogen value constantly decreased with the increase of pressure (0.1–500 MPa). In addition, the colour attributes (L* and a* values) and texture indexes (hardness and chewiness) significantly improved as the pressure increased. The results of low‐field nuclear magnetic resonance demonstrated that the peak area of immobilised water (T22) first enhanced and then declined with the increase of pressure, reaching the maximum value at 200 MPa. Moreover, the integrity of microstructure and protein secondary structure of prepared chicken breast were also disrupted. These findings could serve as a theoretical basis for a better application of HPP in prepared chicken breast meat products. [ABSTRACT FROM AUTHOR]

The phase transition of fullerene C60 under high pressure and high temperature has been widely studied, but the research on the spark‐plasma sintering of C60 is limited, and the mechanical properties of synthesized materials are still unknown. In this study, a series of amorphous carbon materials were synthesized by spark‐plasma sintering fullerene C60 at different temperatures. The structural characterizations showed that they were composed of multi‐graphene fragments with different sizes, curvatures, and ordering degrees. The densities of the synthesized amorphous carbons were 1.3‐1.4 g/cm3, which were lower than the values for graphite, but the mechanical properties were excellent. The highest compressive strength, indentation hardness, and elastic recovery of the amorphous carbons synthesized at different temperatures could reach up to ~1.25 GPa, ~3.8 GPa, and ~85.5%, respectively, which are far better than the values for commercial isotropic graphite materials. [ABSTRACT FROM AUTHOR]

Abstract: The formation of intragranular microstructure in Al2O3/ZrO2 and Si2N2O/Si3N4 nanocomposites was analyzed, and the effect of intragranular microstructure on the mechanical properties of nanocomposites was investigated. Results suggest 3 requisite conditions for the formation of intragranular microstructure and the role of intracrystalline glass phase and scar microstructure. In case of Al2O3/ZrO2, the intragranular microstructure leads to the formation of transgranular fracture, which in turn improves the mechanical properties via strengthening and toughening. On the other hand, in case of Si3N4/Si2N2O nanocomposites, intragranular microstructure reduces the possibility of bridging, pulling out, and crack deflection, thereby leading to the deterioration of strength and toughness. Based on these results, we can conclude that the formation of intragranular microstructure does not necessarily improve the mechanical properties in all kinds of materials. Rather, the effect of intragranular microstructure on the mechanical properties of nanocomposites is related to the strengthening and toughing mechanism of matrix materials. [ABSTRACT FROM AUTHOR]

The softening behavior of a 60 % cold‐drawn Cu‐0.48Cr‐0.16Sn alloy during annealing at temperatures between 450 °C and 750 °C was investigated. The mechanical properties and microstructures evolution of the alloy in both as‐drawn and annealed conditions were analyzed using hardness measurement, transmission electron microscopy (TEM) and electron back‐scatter diffraction (EBSD) technique. The results showed that the softening behavior of the alloy was strongly affected by precipitate coarsening, recovery and recrystallization, and was predominant by recrystallization when the temperature higher than 500 °C. The recrystallization kinetics was characterized by measurements of hardness. The obtained experimental data were evaluated in terms of the Johnson‐Mehl‐Avrami‐Kolmogorov model. The values of the Avrami exponent were ranged from 0.87 to 1.36, and the activation energy of recrystallization was about 117.9 kJ mol‐1 for 60 % cold‐drawn Cu−0.48Cr−0.16Sn alloy, which suggested that recrystallization process of the Cu−Cr−Sn alloy was mainly controlled by grain boundary migration. The softening resistance of the Cu−Cr−Sn alloy is stronger than that of the pure copper due to the addition of Chromium (Cr) and Tin (Sn). In addition, the reduction in strain had a positive effect on the improvement of softening resistance. [ABSTRACT FROM AUTHOR]

The evolution of the microstructure and microsegregation in a new type of Mg–6Al–4Zn–1.2Sn (wt%) cast magnesium alloy solidified at cooling rates from 4.5 × 101 °C s−1 to 2.3 × 103 °C s−1 is investigated. The results indicate that the secondary dendrite arm spacing and the average grain sizes decrease from 14.3 to 2.9 μm and from 187 to 78 μm, respectively, as the cooling rate increases from 4.5 × 101 °C s−1 to 2.3 × 103 °C s−1. The relationship between the secondary dendrite arm spacing (λ2) and cooling rate (R) is fitted as λ2 = 69.7 × R−0.42. When the alloy solidifies in the range of cooling rates, a new quasi‐crystalline I phase is formed due to faster solidification. The microsegregation ratios of Al, Zn, and Sn elements decrease significantly with the increase in cooling rate. Compared with the specimen solidified at 4.5 × 101 °C s−1, the microsegregation ratios of Al, Zn, and Sn of that solidified at a cooling rate of 2.3 × 103 °C s−1 decrease by 37.4%, 45.7%, and 31.6%, respectively. [ABSTRACT FROM AUTHOR]

The isothermal compression experiments with the strain rates of 0.01–10 s−1 and deformation temperature range of 300–420 °C are performed to investigate the hot deformation behavior of A356 aluminum alloy. Also, the complex deformation mechanisms are analyzed. It is found that, as the strain is gradually increased, the flow stress first rises, and then the stable stress appears without a tangible peak. The microstructures exhibit large elongated grains, and only a few small new grains appear under most deformation conditions. It is because the dynamic recovery (DRV) is the dominant softening mechanism. Based on the measured data, both the original Johnson–Cook (O–JC) model and modified Johnson–Cook model (M–JC) are built for the tested aluminum alloy. However, there are different deviations between the experimental and the predicted true stresses by O–JC model and M–JC model. Considering the obvious DRV features, an enhanced Johnson–Cook (EH–JC) model is proposed by introducing the stress–dislocation relation. The accuracy of the EH–JC model is validated because the correlation coefficient between the experimental and predicted results is as high as 0.997, whereas the average absolute relative error is merely 2.84%. [ABSTRACT FROM AUTHOR]