High-entropy materials possess high hardness and strong wear resistance,yet the key bottleneck for their practical applications is the poor corrosion resistance in harsh *** this work,the high-entropy nitride(HEN)coat...
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High-entropy materials possess high hardness and strong wear resistance,yet the key bottleneck for their practical applications is the poor corrosion resistance in harsh *** this work,the high-entropy nitride(HEN)coatings of(MoNbTaTiZr)1-xNx(x=0-0.47)were fabricated using a hybrid di-rect current magnetron sputtering *** research focus was dedicated to the effect of nitrogen content on the microstructure,mechanical and electrochemical *** results showed that the as-deposited coatings exhibited a typical body-centered cubic(BCC)structure without nitrogen,while the amorphous matrix with face-centered cubic(FCC)nanocrystalline grain was observed at x=*** increasing x in the range of 0.35-0.47 caused the appearance of polycrystalline FCC phase in *** with the MoNbTaTiZr metallic coating,the coating containing nitrogen favored the high hard-ness around 13.7-32.4 GPa,accompanied by excellent tolerance both against elastic and plastic ***,such N-containing coatings yielded a low corrosion current density of about 10-8-10-7 A/cm2 and high electrochemical impedance of 106 Ω cm2 in 3.5 wt.%NaCl solution,indicating the supe-rior corrosion *** reason for the enhanced electrochemical behavior could be ascribed to the spontaneous formation of protective passive layers over the coating surface,which consisted of the domi-nated multi-elemental oxides in chemical ***,noted that the(MoNbTaTiZr)0.83N0.17 coat-ing displayed the highest hardness of 32.4±2.6 GPa and H/E ratio at 0.09,together with remarkable cor-rosion resistance,proposing the strongest capability for harsh-environmental applications required both good anti-wear and anti-corrosion performance.
The microstructure evolution and mechanical properties of Cu-bearing ferritic stainless steel with diferent Cr addition(Cr=12,15 and 17 wt%)were *** phase transformation behavior under diferent cooling rate,Cu-rich pr...
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The microstructure evolution and mechanical properties of Cu-bearing ferritic stainless steel with diferent Cr addition(Cr=12,15 and 17 wt%)were *** phase transformation behavior under diferent cooling rate,Cu-rich precipitation behavior and its infuence on the mechanical properties under diferent aging treatment are systematically characterized using dilatometry,diferential scanning calorimeter(DSC)and transmission electron microscopy(TEM).The results indicated that the increase in Cr content narrowed the austenite phase region at high temperatures,afecting its microstructure under diferent cooling *** 12Cr-1.5Cu steel exhibited a fully austenitic phase region at high temperature and occurred apparent martensitic transformation after air *** rate signifcantly infuenced the phase transition of the steels,and subsequently afected its mechanical *** three investigated steels showed higher strength and lower plasticity in air cooling condition compared to furnace cooling condition,due to the presence of *** aging treatment,high number densities of Cu-rich precipitates were formed in steel matrix and the size of Cu-rich precipitates increased obviously with increasing aging temperature,while the tendency for number density was *** and dispersed Cu-rich precipitates formed during low-temperature aging enhanced strength of the steels,while larger Cu-rich phases developed during high-temperature aging endowed greater ductility to the ***,the Cr content had no signifcant efect on the precipitation behavior of Cu-rich *** comprehensive results and analyses could provide a solid foundation for broader applications of Cu-bearing ferritic stainless steels.
Multiphase microstructure significantly increases the strength,usually at the expense of flangeability because of lacking microstructure *** further improve the strength-flangeability of multiphase steel,the microstru...
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Multiphase microstructure significantly increases the strength,usually at the expense of flangeability because of lacking microstructure *** further improve the strength-flangeability of multiphase steel,the microstructural homogeneity was advanced by adjusting the hard martensite/austenite(M/A)*** strength-flangeability was measured via uniaxial tensile tests and hole expansion *** microstructures were characterized using a scanning electron microscope equipped with an electron backscatter diffraction detector and a transmission electron *** tests were supplementally used to quantitatively reveal the microstructural homogeneity of the *** show that the adjusted multiphase steel achieves an excellent ultimate tensile strength(~800 MPa)and flangeability(~135%hole expansion ratio).A promising homogeneous multiphase microstructure was obtained by controlling undercooled austenite transformed at about 600℃.This microstructure consists of soft polygonal ferrite,blocky bainitic ferrite,and hard M/A *** volume fraction of M/A islands is around 5%,and the average size is less than l *** nanoindentation analysis indicated that the participation of M/A islands impressively influenced the microstructural *** strain partition and better mechanical compatibility were present in the adjusted multiphase steel since the plasticity initiation started late,which resulted in a positive ***,avoiding M/A islands distributed in the chain along the rolling direction on the matrix hindered the possibility of voids coalescing into cracks and stabilized the flanging performance.
Soft electromechanical sensors have led to a new paradigm of electronic devices for novel motion-based wearable applications in our daily lives. However, the vast amount of random and unidentified signals generated by...
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Soft electromechanical sensors have led to a new paradigm of electronic devices for novel motion-based wearable applications in our daily lives. However, the vast amount of random and unidentified signals generated by complex body motions has hindered the precise recognition and practical application of this technology. Recent advancements in artificial-intelligence technology have enabled significant strides in extracting features from massive and intricate data sets, thereby presenting a breakthrough in utilizing wearable sensors for practical applications. Beyond traditional machine-learning techniques for classifying simple gestures, advanced machine-learning algorithms have been developed to handle more complex and nuanced motion-based tasks with restricted training data sets. Machine-learning techniques have improved the ability to perceive, and thus machine-learned wearable soft sensors have enabled accurate and rapid human-gesture recognition, providing real-time feedback to users. This forms a crucial component of future wearable electronics, contributing to a robust human–machine interface. In this review, we provide a comprehensive summary covering materials, structures and machine-learning algorithms for hand-gesture recognition and possible practical applications through machine-learned wearable electromechanical sensors.
Laser powder bed fusion (LPBF) is a commonly used additive manufacturing (AM) method for efficiently producing intricate geometric components. This investigation examines factors such as pores, cellular structure, gra...
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Laser powder bed fusion (LPBF) is a commonly used additive manufacturing (AM) method for efficiently producing intricate geometric components. This investigation examines factors such as pores, cellular structure, grain size, and inclusions from the manufacturing process that contribute to the corrosion resistance of LPBF DSS. Furthermore, the as-built LPBF duplex stainless steel (DSS) is primarily ferrite due to the rapid cooling process. Therefore, the transformation of ferrite to austenite after various heat treatments in LPBF DSS and its corresponding corrosion resistance are presented. Additionally, a new mixed powder method is proposed to increase the austenite content in the as-built LPBF DSS. This review also focuses on the passivation capability and pitting corrosion performance in LPBF and conventional DSS. This article summarizes the variations in microstructure between as-built and heat-treated LPBF DSS, with their impacts on corrosion resistance, offering insights for manufacturing highly corrosion-resistant LPBF DSS.
Grasping task is one of the crucial objectives in activities of daily living. However, elderly human subjects are facing significant challenges when attempting to perform grasping task. In this regard, a hand exoskele...
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High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding *** influence of Ar plasma activation on surface morphology is *** the annealing temperature is 300℃,the bonding strength reaches ...
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High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding *** influence of Ar plasma activation on surface morphology is *** the annealing temperature is 300℃,the bonding strength reaches a maximum of 6.2 *** addition,a thermal stress model for GaAs/Si wafers is established based on finite element analysis to obtain the distribution of equivalent stress and deformation variables at different *** shape varia-tion of the wafer is directly proportional to the annealing *** an annealing temperature of 400℃,the maximum protrusion of 4 inches GaAs/Si wafers is 3.6 *** interface of GaAs/Si wafers is observed to be dense and defect-free using a transmission electron *** characterization of interface elements by X-ray energy dispersion spectroscopy indi-cates that the elements at the interface undergo mutual diffusion,which is beneficial for improving the bonding strength of the *** is an amorphous transition layer with a thickness of about 5 nm at the bonding *** preparation of Si-based GaAs heterojunctions can enrich the types of materials required for the development of integrated circuits,improve the performance of materials and devices,and promote the development of microelectronics technology.
Gel-based polymer electrolytes are limited by the polarity of the residual solvent,which restricts the coupling-breaking behaviour during Li^(+)conduction,resulting in the Li^(+)transport kinetics being greatly ***,we...
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Gel-based polymer electrolytes are limited by the polarity of the residual solvent,which restricts the coupling-breaking behaviour during Li^(+)conduction,resulting in the Li^(+)transport kinetics being greatly ***,we designed anion competitive gel polymer electrolyte(ACPE)by introducing lithium difluoro(oxalato)borate(LiDFOB)anion into the 1,3-dioxolane(DOL)in situ polymerisation *** enhances the ionic dipole interaction between Li^(+)and the solvent molecules and synergizes with Li^(+)across the solvation site of the polymer ethylene oxide(EO)unit,combination that greatly improves the Li^(+)transport *** a result,ACPE exhibits 1.12 mS cm^(−1)ionic conductivity and 0.75 Li^(+)transfer number at room ***,this intra-polymer solvation sheath allows preferential desolvation of DFOB−,which contributes to the formation of kinetically stable anion-derived interphase and effectively mitigates side *** results demonstrate that the assembled Li||NCM622 solid-state battery exhibits lifespan of over 300 cycles with average Coulombic efficiency of 98.8%and capacity retention of 80.3%.This study introduces a novel approach for ion migration and interface design,paving the way for high-safety and high-energy-density batteries.
Lithium-sulfur(Li-S)batteries have attracted extensive attention due to ultrahigh theoretical energy density of 2600 Wh kg^(-1).Liquid-solid deposition from dissolved lithium polysulfides(LiPSs)to solid lithium sulfid...
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Lithium-sulfur(Li-S)batteries have attracted extensive attention due to ultrahigh theoretical energy density of 2600 Wh kg^(-1).Liquid-solid deposition from dissolved lithium polysulfides(LiPSs)to solid lithium sulfide(Li_(2)S)largely determines the actual battery ***,a premature liquidsolid deposition process of LiPSs is revealed at higher thermodynamic potential than Li_(2)S deposition in Li-S *** premature solid deposit exhibits higher chemical state and hemispherical morphology in comparison with Li_(2)S,and the premature deposition process is slower in kinetics and higher in deposition ***,a supersaturation deposition mechanism is proposed to rationalize the above findings based on thermodynamic *** work demonstrates a unique premature liquid-solid deposition process of Li-S batteries.
The identification of indoor harmful gases is imperative due to their significant threats to human health and *** achieve accurate identification,an effective strategy of constructing a sensor array combined with the ...
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The identification of indoor harmful gases is imperative due to their significant threats to human health and *** achieve accurate identification,an effective strategy of constructing a sensor array combined with the pattern recognition algorithm is ***-based thin-film transistors are selected as the sensor array unit,with semiconductor carbon nanotubes(CNTs)within the TFT channels modified with different metals(Au,Cu and Ti)for selective responses to NH_(3),H_(2)S and HCHO,*** accurate gas species identification,an identification mode that combines linear discriminant analysis algorithms and logistic regression classifier is *** test results demonstrate that by preprocessing the sensor array’s sensing data with the LDA algorithm and subsequently employing the LR classifier for identification,a 100%recognition rate can be achieved for three target gases(NH3,H2S and HCHO).This work provides significant guidance for future applications of chip-level gas sensors in the realms of the Internet of Things and Artificial Intelligence.
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