The impact of different Ta contents on the mechanical properties and thermoplastic forming ability of in-situ Taparticle reinforced Zr–Cu–Al–Ni bulk metallic glass composites was studied. The composition(Zr55Cu30Al...
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The impact of different Ta contents on the mechanical properties and thermoplastic forming ability of in-situ Taparticle reinforced Zr–Cu–Al–Ni bulk metallic glass composites was studied. The composition(Zr55Cu30Al10-Ni5)94Ta6with the best comprehensive performance was chose for a systematic investigation into its thermoplastic behavior in the supercooled liquid region（SLR）, with quantitative analysis conducted by the strain rate sensitivity index and activation volume. The steady-state flow stress and the stress overshoot intensity were augmented with deformation temperature decreasing, strain rate increasing, and the addition of the secondary phase, leading to a transition from Newtonian to non-Newtonian flow regime. The addition of the secondary phase deteriorated the rheological properties of the material. To solve the problem that the Maxwell-Pulse constitutive model showed an inability to accurately describe the steady-state flow process. A modified constitutive relationship, introducing the effect of the volume fraction of Ta particles on viscosity and elastic modulus in the steady-state flow process which was ignored in Maxwell-pulse model, was established. The fitting results of the true stress-strain curves of the modified Maxwell-pulse constitutive model were in better agreement with the experimental date than those of the Maxwell-pulse constitutive model, with higher prediction accuracy. The modified constitutive model well predicted the thermoplastic deformation behavior of(Zr55Cu30Al10Ni5)*** influence mechanism of Ta particles on the flow behavior was explained that Ta particles increased the viscosity of amorphous matrix, thereby hindering its flow and ultimately leading to an increase in flow stress.
Additive manufacturing(AM),also called three-dimensional(3D)printing,offers disruptive design freedom and manufacturing flexibility due to the layer-wise incremental formation manner of *** in AM techniques provide un...
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Additive manufacturing(AM),also called three-dimensional(3D)printing,offers disruptive design freedom and manufacturing flexibility due to the layer-wise incremental formation manner of *** in AM techniques provide unique advantages and feasibilities for overcoming challenges arising from fabricating parts with complexities in geometry,materials,and properties.
The point-to-point contact mechanism in all-solid-state Li-S batteries(ASSLSBs)is not as efficient as a liquid electrolyte which has superior mobility in the electrode,resulting in a slower reaction kinetics and inade...
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The point-to-point contact mechanism in all-solid-state Li-S batteries(ASSLSBs)is not as efficient as a liquid electrolyte which has superior mobility in the electrode,resulting in a slower reaction kinetics and inadequate ionic/electronic conduction network between the S(or Li_(2)S),conductive carbon,and solid-state electrolytes(SSEs)for achieving a swift(dis)charge ***,a series of hybrid ionic/electronic conduction triple-phase interfaces with transition metal and nitrogen co-doping were *** graphitic ordered mesoporous carbon frameworks(TM-N-OMCs;TM=Fe,Co,Ni,and Cu)serve as hosts for Li_(2)S and Li_(6)PS_(5)Cl(LPSC)and provide abundant reaction sites on the triple *** from both experimental and computational research display that the combination of Cu-N co-dopants can promote the Li-ion diffusion for rapid transformation of Li_(2)S with adequate ionic(6.73×10^(−4)S·cm^(−1))/electronic conductivities(1.77×10^(−2)S·cm^(−1))at 25℃.The as-acquired Li_(2)S/Cu-N-OMC/LPSC electrode exhibits a high reversible capacity(1147.7 mAh·g^(−1))at 0.1 C,excellent capacity retention(99.5%)after 500 cycles at 0.5 C,and high areal capacity(7.08 mAh·cm^(−2)).
In this work,a new treatment method combining ultrasonic vibration with FeCoNiCrCu high entropy alloy(HEA)coating was used to prepared Al/Mg bimetal through the lost foam compound *** effects of composite treatment in...
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In this work,a new treatment method combining ultrasonic vibration with FeCoNiCrCu high entropy alloy(HEA)coating was used to prepared Al/Mg bimetal through the lost foam compound *** effects of composite treatment involving ultrasonic vibration and HEA coating on interfacial microstructure and mechanical properties of Al/Mg bimetal were *** demonstrate that the interface thickness of the Al/Mg bimetal with composite treatment significantly decreases to only 26.99%of the thickness observed in the untreated Al/Mg *** HEA coating hinders the diffusion between Al and Mg,resulting the significant reduction in Al/Mg intermetallic compounds in the *** Al/Mg bimetal interface with composite treatment is composed of Al_(3)Mg_(2)and Mg_(2)Si/AlxFeCoNiCrCu+FeCoNiCrCu/δ-Mg+Al_(12)Mg_(17)eutectic *** interface resulting from the composite treatment has a lower hardness than that without *** acoustic cavitation and acoustic streaming effects generated by ultrasonic vibration promote the diffusion of Al elements within the HEA coating,resulting in a significant improvement in the metallurgical bonding quality on the Mg *** fracture position shifts from the Mg side of the Al/Mg bimetal only with HEA coating to the Al side with composite *** shear strength of the Al/Mg bimetal increases from 32.16 MPa without treatment to 63.44 MPa with ultrasonic vibration and HEA coating,increasing by 97.26%.
Vanadium nitride(VN)has received significant attention as a potential negative electrode material due to its remarkable theoretical and physical ***,the electrochemical performance needs to be improved due to its low ...
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Vanadium nitride(VN)has received significant attention as a potential negative electrode material due to its remarkable theoretical and physical ***,the electrochemical performance needs to be improved due to its low specific surface area and the issue of being easily dissolved in *** have shown that the composite structure of carbon-coated nano sc ale VN particles could significantly increase the specific surface area of VN,and more importantly,and the carbon matrix can effectively restrain the dissolution of VN particles in the electrolyte,thereby improving its chemical and electrochemical performance,including specific capacity and cycling ***,VN quantum dots are synthesized and protected by uniformly coating the carbon skeleton on its surface via an in situ strategy of oxidation initiation,which initiates dopamine polymerization,forming a crystalline complex of polydopamine and *** heat treatment,the product is a composite material with VN quantum dots embedded in the amorphous carbon *** resulting smallsized and crosslinked carbon particles formed a graded pore structure,more reasonable channels provided for electrolyte ions transport *** the composite material was used as the negative electrode material for supercapacitors,it exhibits the specific capacity of 391.9 F·g^(-1)at a current density of 0.5 A·g^(-1)and excellent capacity retention rate of 83.6%after *** synthesis method of this quantum dot could be applied to other metal compounds and has potential applications in catalysis,environmental protection,and other fields.
Design: of shape memory alloys with large phase transformation strain and low hysteresis is in demand for practical applications that require high output work and high precision. However, this remains challenging due ...
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Design: of shape memory alloys with large phase transformation strain and low hysteresis is in demand for practical applications that require high output work and high precision. However, this remains challenging due to the competition between these two properties. In this work, we report a method that combines machine learning with multi-objective optimization to assist the rapid design of shape memory alloys. Instead of directly using the predictions from machine learning to guide experiments, this work employs the uncertainty-aware two-objective optimization algorithm to recommend the potential candidates. Such a strategy is beneficial to the case where limited data is available just as the dataset of twenty Ni Ti-based alloys with hysteresis and phase transformation strain established herein. key features are screened out from a relatively large feature pool and Gaussian regression models are built for predicting the two properties of unknown alloys. At the end, eight alloys with promise to improve both recoverable strain and hysteresis are recommended, as compared to the alloys in the initial dataset.
As a superior alternative to sutures,tissue adhesives have been developed significantly in recent ***,existing tissue adhesives struggle to form fast and stable adhesion between tissue interfaces,bond weakly in wet en...
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As a superior alternative to sutures,tissue adhesives have been developed significantly in recent ***,existing tissue adhesives struggle to form fast and stable adhesion between tissue interfaces,bond weakly in wet environments and lack *** this study,a degradable and bioactive citrate-based polyurethane adhesive is constructed to achieve rapid and strong tissue *** hydrophobic layer was created with polycaprolactone to overcome the bonding failure between tissue and adhesion layer in wet environments,which can effectively improve the wet bonding *** citrate-based polyurethane adhesive provides rapid,non-invasive,liquid-tight and seamless closure of skin incisions,overcoming the limitations of sutures and commercial tissue *** addition,it exhibits biocompatibility,biodegradability and hemostatic *** degradation product citrate could promote the process of angiogenesis and accelerate wound *** study provides a novel approach to the development of a fast-adhering wet tissue adhesive and provides a valuable contribution to the development of polyurethane-based tissue adhesives.
Shock responses of Mg-Al-Zn alloy are investigated by the molecular dynamics(MD)*** wave propagation,plastic deformation behavior and failure mechanism along the[0001]and[1010]orientations are *** both orientations,si...
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Shock responses of Mg-Al-Zn alloy are investigated by the molecular dynamics(MD)*** wave propagation,plastic deformation behavior and failure mechanism along the[0001]and[1010]orientations are *** both orientations,simulation results show that the shock wave has an obvious double-wave structure(plastic-elastic)under a piston velocity of 1200 m/s.A higher Hugoniot elastic limit(HEL)is observed for[0001]-oriented *** the shock pressure is along the[1010]direction,the distance between plastic and elastic waves is closer,and higher dislocation density and more twins are ***,the spall strength for[1010]-oriented shock is predicted to be *** addition,the wave interactions,HEL and spall strength predicted for Mg-Al-Zn alloy are compared with the experimental results and MD simulation results of Mg single crystal in the *** is concluded that the shock performance of Mg-Al-Zn is better than that of Mg single crystal.
It is a practically significant issue to refine and modify industrial Al-Si casting alloy to improve its *** the present study,a novel refiner Al-3Ti-4.35La alloy,prepared by a melt-reaction method,was used,combined w...
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It is a practically significant issue to refine and modify industrial Al-Si casting alloy to improve its *** the present study,a novel refiner Al-3Ti-4.35La alloy,prepared by a melt-reaction method,was used,combined with Sr to refine the as-cast A356 *** effects on the as-cast microstructures and mechanical properties of A356 alloy were *** results indicate that the combined addition of Al-3Ti-4.35La intermediate alloy and Sr can improve the microstructure and enhance the mechanical properties of A356 *** adding 0.3wt.%Al-3Ti-4.35La and 0.03wt.%Sr to the as-cast A356 alloy,the average grain size ofα-Al decreases from 693.47μm to 264.13μm(a decrease of 61.91%),the secondary dendrite arm spacing(SDAS)is decreased by 47.8%from 32.09μm to 16.75μm,and the eutectic Si is transformed from an acicular structure to short rods and a granular *** ultimate tensile strength(UTS)and elongation(EL)of the as-cast A356 alloy modified by Al-3Ti-4.35La and Sr reach 216.3 MPa and 10.6%,which are enhanced by 29.54%and 134.66%compared with the unmodified alloy,*** fracture mode is transformed from transgranular fracture to intergranular fracture,and the ductile toughness of the alloy is *** adding the Al-3Ti-4.35La and Sr,the undercooling for the nucleation ofα-Al and eutectic Si increases,leading to an accelerated nucleation rate and an increased number of nuclei,which shortens the duration of the eutectic reaction and consequently inhibits grain growth.
Proton exchange membrane water electrolysis(PEMWE)plays a critical role in practical hydrogen *** for the electrode activities,the widespread deployment of PEMWE is severely obstructed by the poor electron-proton perm...
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Proton exchange membrane water electrolysis(PEMWE)plays a critical role in practical hydrogen *** for the electrode activities,the widespread deployment of PEMWE is severely obstructed by the poor electron-proton permeability across the catalyst layer(CL)and the inefficient transport *** this work,the PEDOT:F(Poly(3,4-ethylenedioxythiophene):perfluorosulfonic acid)ionomers with mixed proton-electron conductor(MPEC)were fabricated,which allows for a homogeneous anodic CL structure and the construction of a highly efficient triple-phase *** PEDOT:F exhibits strong perfluorosulfonic acid(PFSA)side chain extensibility,enabling the formation of large hydrophilic ion clusters that form proton-electron transport channels within the CL networks,thus contributing to the surface reactant water *** PEMWE device employing membrane electrode assembly(MEA)prepared by PEDOT:F-2 demonstrates a competitive voltage of 1.713 V under a water-splitting current of 2 A cm^(-2)(1.746 V at 2A cm^(-2) for MEA prepared by Nafion D520),along with exceptional long-term ***,the MEA prepared by PEDOT:F-2 also exhibits lower ohmic resistance,which is reduced by 23.4%and 17.6%at 0.1 A cm^(-2) and 1.5 A cm^(-2),respectively,as compared to the MEA prepared by *** augmentation can be ascribed to the superior proton and electron conductivity inherent in PEDOT:F,coupled with its remarkable structural *** characteristic enables expeditious mass transfer during electrolytic reactions,thereby enhancing the performance of PEMWE devices.
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