The magnesium matrix double interpenetrating composites reinforced by nickel foam were fabricated by pressureless infiltration technology.Then the morphology of the nickel reinforcement and the microstructures of comp...The magnesium matrix double interpenetrating composites reinforced by nickel foam were fabricated by pressureless infiltration technology.Then the morphology of the nickel reinforcement and the microstructures of composites were characterized by SEM.The results show that not only is the nickel foam reinforcement reticular in three dimensions,but also the struts of foam keep the network structure,which ensures that the Ni foam/Mg composites are double interpenetrating.The interface bonding of composites between magnesium matrix and nickel foam reinforcement is good,without reaction around the interface,which is the indispensable condition that advanced composites should possess.Magnesium matrix distributes in the windows of nickel foam,the triangle center holes and microhole of nickel struts,and the composites have double interpenetrating structure,which makes the composites have unique properties.展开更多
The frequent occurrence of safety accidents during the calendering process is caused by the flammable and explosive properties of composite modified double-base(CMDB)propellant.Optimization of process parameters with ...The frequent occurrence of safety accidents during the calendering process is caused by the flammable and explosive properties of composite modified double-base(CMDB)propellant.Optimization of process parameters with the aid of fluid simulation technology could effectively ensure the safety of the calendering process.To improve the accuracy of the simulation results,material parameters and model structure were corrected based on actual conditions,and adaptive grid technology was applied in the local mesh refinement.In addition,the rheological behavior,motion trajectories and heat transfer mechanisms of CMDB propellant slurry were studied with different gaps,rotational rates and temperatures of two rollers.The results indicated that the refined mesh could significantly improve the contour clarity of boundaries and simulate the characteristics of CMDB propellant slurry reflux movement caused by the convergent flow near the outlet.Compared with the gap,the increased rotational rate of roller could promote the reflux movement and intensify the shear flow of slurry inside the flow region by viscous shear dragging.Meanwhile,under the synergistic effect of contact heat transfer as well as convective heat exchange,heat accumulated near the outlet and diffused along the reflux movement,which led to the countercurrent heat dissipation behavior of CMDB propellant slurry.The plasticizing mechanism of slurry and the safety of calendering under different conditions were explored,which provided theoretical guidance and reference data for the optimization of calendering process conditions.Based on the simulation results,the safety of the CMDB propellant calendering process could be significantly improved with a few tests conducted during a short research and development cycle.展开更多
Relatively well crystallized and high aspect ratio Mg-Al layered double hydroxides（LDHs） were prepared by coprecipitation process in aqueous solution and further rehydrated to an organic modified LDH（OLDH） in the ...Relatively well crystallized and high aspect ratio Mg-Al layered double hydroxides（LDHs） were prepared by coprecipitation process in aqueous solution and further rehydrated to an organic modified LDH（OLDH） in the presence of surfactant. The intercalated structure and high aspect ratio of OLDH were verified by X-ray diffraction（XRD） and scanning electron microscopy（SEM）. A series of poly（propylene carbonate）（PPC）/OLDH composite films with different contents of OLDH were prepared via a melt-blending method. Their cross section morphologies, gas barrier properties and tensile strength were investigated as a function of OLDH contents. SEM results show that OLDH platelets are well dispersed within the composites and oriented parallel to the composite sheet plane. The gas barrier properties and tensile strength are obviously enhanced upon the incorporation of OLDH. Particularly, PPC/2%OLDH film exhibits the best barrier properties among all the composite films. Compared with pure PPC, the oxygen permeability coefficient（OP） and water vapor permeability coefficient（WVP） is reduced by 54% and 17% respectively with 2% OLDH addition. Furthermore, the tensile strength of PPC/2%OLDH is 83% higher than that of pure PPC with only small lose of elongation at break. Therefore, PPC/OLDH composite films show great potential application in packaging materials due to its biodegradable properties, superior oxygen and moisture barrier characteristics.展开更多
A manufacturing method is proposed for carbon based composite double polymer compliant electrode.The stiffness of this compliant electrode is changed by adjusting the mass fraction of carbon black and the ratios betwe...A manufacturing method is proposed for carbon based composite double polymer compliant electrode.The stiffness of this compliant electrode is changed by adjusting the mass fraction of carbon black and the ratios between Ecoflex20 and RT625.Tensile machine is used to test its ductility and hardness.The conductivity is measured through the source table.Finally,it is printed on the dielectric elastomers(DE)film,and the high-voltage amplifier is used for dielectric elastomers actuators(DEAs)dynamics testing.The results show that the compliant electrode has high tensile properties(>200%),low stiffness(<300 kPa)and well conductivity(0.0493 S/cm).It is proved that the DEAs displacement output is up to 1.189 mm by this compliant electrode under dynamic response,which is 1.64 times and 1.32 times of the same type.Moreover,this formula extends the curing time of the original compliant electrode ink.It can provide a reference for the production of compliant electrode and DEAs in the future.展开更多
In this paper, the tensile properties of the MWK structures produced with different basic stitches for composite reinforcement were experimentally studied. The results show that the MWK structures with the double loop...In this paper, the tensile properties of the MWK structures produced with different basic stitches for composite reinforcement were experimentally studied. The results show that the MWK structures with the double loop pillar stitches have better mechanical properties.展开更多
Ni-W-P composite coatings reinforced by Ce O2 and Si O2 nano-particles on the surface of common carbon steels, were prepared by double pulse electrodeposition. The crystallization course was characterized by phase str...Ni-W-P composite coatings reinforced by Ce O2 and Si O2 nano-particles on the surface of common carbon steels, were prepared by double pulse electrodeposition. The crystallization course was characterized by phase structures, crystallinity, grain sizes and microstructures. The results indicate that as-deposited composite coating is amorphous. Whereas it turns into the crystalline structure with 98.25% crystallinity, and Ni3 P, Ni2 P and Ni5P2 alloy phases precipitate from structures at 400 °C. Thereafter, Ni2 P and Ni5P2 metastable alloy phases turn into Ni3 P stable alloy phase at 500 °C. The crystallization course of the composite coating has finished when being heat-treated at 700 °C. The average sizes of Ni grains increase with the rise of heat treatment temperature from400 °C to 700 °C. Ce O2 and Si O2 nano-particles deposited into Ni-W-P alloys can delay the crystallization course and habit the growth of alloy phases.展开更多
In order to investigate the damage characteristic of ceramic-metal interpenetrating phase composite（IPC） under dynamic loading, uniaxial dynamic compression was performed to characterize the failure of SiC/Al compos...In order to investigate the damage characteristic of ceramic-metal interpenetrating phase composite（IPC） under dynamic loading, uniaxial dynamic compression was performed to characterize the failure of SiC/Al composite with 15% porosity using a modifi ed Split Hopkinson Pressure Bar（SHPB）. High speed photography was used to capture the failure procedure and set up the relationship between deformation and real stress. The deformation control technology was used to obtain collected samples in different deformations under dynamic loading. Micro CT technology was utilized to acquire real damage distribution of these specimens. Moreover, SEM was employed in comparing the damage characteristics in IPC. A summary of the available experimental results showed that IPC without lateral confi nement formed double cones. The different features compared with ceramic materials without restraint was shown to be the result of the lateral restraint effect provided by metal phase to ceramics skeleton.展开更多
A double network nested foam composite with tunable electromagnetic wave absorption performance was fabricated via a carbonization,impregnation,and chemical vapor infiltration method.The research results indicated tha...A double network nested foam composite with tunable electromagnetic wave absorption performance was fabricated via a carbonization,impregnation,and chemical vapor infiltration method.The research results indicated that the three-dimensional interconnected carbon foam was successfully enhanced by the SiC nanowire network.As expected,the electromagnetic absorption performance of the as-prepared SiC nanowire reinforced carbon foam(SiC_(nw)/CF)was greatly improved by the introduction of the SiC nanowires.The SiC_(nw)/CF composite prepared with a lower concentration of Ni catalyst possessed an excellent microwave absorption property with the lowest reflection loss value of-36.31 dB with a matched thickness of 2.60 mm accompanied by the widest effective bandwidth of 4.52 dB.An increase in catalyst concentration degraded the electromagnetic absorption ability to a certain extent.A potential microwave absorption schematic diagram was finally proposed,and it stated that the SiC nanowire network played an essential role in the improvement of the electromagnetic absorption properties.展开更多
Halide solid state electrolytes(SSEs)have attracted significant attention due to their outstanding advantages of better cathodic stability and higher ionic conductivity.However,the most halide SSEs are unstable agains...Halide solid state electrolytes(SSEs)have attracted significant attention due to their outstanding advantages of better cathodic stability and higher ionic conductivity.However,the most halide SSEs are unstable against lithium,preventing their direct use with lithium anodes and thus sacrificing the energy density of all solid-state lithium batteries(AsSLBs),which significantly limits their application.Conventional strategies,such as employing Li-In anode or sulfide interface layer,suffer from reduced energy density or interfacial incompatibility.Employing a halide of the same family as the interface layer,instead of the chemically dissimilar sulfide SSEs,is expected to resolve the interfacial compatibility problem.Herein,we propose an all-halide double composite electrolyte(LTLC-LZC),where Li_(2)ZrCl_(6)(LZC)serves as the bulk layer and Li_(0.388)Ta_(0.238)La_(0.475)Cl_(3)(LTLC)functions as the anode-side interfacial contact layer.The two halide electrolytes exhibit excellent chemical compatibility and comparable processability,enabling facile cold-pressed bilayer assembly.Compared with single-layer LZC,the LTLC-LZC electrolyte significantly enhances interfacial stability and ionic conductivity.Therefore,Li|LTLC-LZC|Li symmetric cells cycle stably for over 2500 h,while Li|LTLC-LZC|NCM622 full cells deliver high initial coulombic efficiency and maintain~100%coulombic efficiency during cycling.This work provides a viable pathway toward practical high-energy halide-based AsSLBs.展开更多
基金Project(07JD06)supported by Science Research Foundation of East China Jiaotong University,ChinaProject(09497)supported by Young Science Foundation of Jiangxi Province Education Office,China+1 种基金Project(2009GQC0014)supported by the Natural Science Foundation of Jiangxi Province,ChinaProject(50765005)supported by the National Natural Science Foundation of China
文摘The magnesium matrix double interpenetrating composites reinforced by nickel foam were fabricated by pressureless infiltration technology.Then the morphology of the nickel reinforcement and the microstructures of composites were characterized by SEM.The results show that not only is the nickel foam reinforcement reticular in three dimensions,but also the struts of foam keep the network structure,which ensures that the Ni foam/Mg composites are double interpenetrating.The interface bonding of composites between magnesium matrix and nickel foam reinforcement is good,without reaction around the interface,which is the indispensable condition that advanced composites should possess.Magnesium matrix distributes in the windows of nickel foam,the triangle center holes and microhole of nickel struts,and the composites have double interpenetrating structure,which makes the composites have unique properties.
文摘The frequent occurrence of safety accidents during the calendering process is caused by the flammable and explosive properties of composite modified double-base(CMDB)propellant.Optimization of process parameters with the aid of fluid simulation technology could effectively ensure the safety of the calendering process.To improve the accuracy of the simulation results,material parameters and model structure were corrected based on actual conditions,and adaptive grid technology was applied in the local mesh refinement.In addition,the rheological behavior,motion trajectories and heat transfer mechanisms of CMDB propellant slurry were studied with different gaps,rotational rates and temperatures of two rollers.The results indicated that the refined mesh could significantly improve the contour clarity of boundaries and simulate the characteristics of CMDB propellant slurry reflux movement caused by the convergent flow near the outlet.Compared with the gap,the increased rotational rate of roller could promote the reflux movement and intensify the shear flow of slurry inside the flow region by viscous shear dragging.Meanwhile,under the synergistic effect of contact heat transfer as well as convective heat exchange,heat accumulated near the outlet and diffused along the reflux movement,which led to the countercurrent heat dissipation behavior of CMDB propellant slurry.The plasticizing mechanism of slurry and the safety of calendering under different conditions were explored,which provided theoretical guidance and reference data for the optimization of calendering process conditions.Based on the simulation results,the safety of the CMDB propellant calendering process could be significantly improved with a few tests conducted during a short research and development cycle.
基金financially supported by the National Natural Science Foundation of China(No.21376276)the Specialfunded Program on National Key Scientific Instruments and Equipment Development of China(No.2012YQ230043)+1 种基金Guangdong Province Sci&Tech Bureau(Key Strategic Project No.2008A080800024)the Fundamental Research Funds for the Central Universities
文摘Relatively well crystallized and high aspect ratio Mg-Al layered double hydroxides（LDHs） were prepared by coprecipitation process in aqueous solution and further rehydrated to an organic modified LDH（OLDH） in the presence of surfactant. The intercalated structure and high aspect ratio of OLDH were verified by X-ray diffraction（XRD） and scanning electron microscopy（SEM）. A series of poly（propylene carbonate）（PPC）/OLDH composite films with different contents of OLDH were prepared via a melt-blending method. Their cross section morphologies, gas barrier properties and tensile strength were investigated as a function of OLDH contents. SEM results show that OLDH platelets are well dispersed within the composites and oriented parallel to the composite sheet plane. The gas barrier properties and tensile strength are obviously enhanced upon the incorporation of OLDH. Particularly, PPC/2%OLDH film exhibits the best barrier properties among all the composite films. Compared with pure PPC, the oxygen permeability coefficient（OP） and water vapor permeability coefficient（WVP） is reduced by 54% and 17% respectively with 2% OLDH addition. Furthermore, the tensile strength of PPC/2%OLDH is 83% higher than that of pure PPC with only small lose of elongation at break. Therefore, PPC/OLDH composite films show great potential application in packaging materials due to its biodegradable properties, superior oxygen and moisture barrier characteristics.
基金Science and Technology Talent Project of Xi’an Science and Technology Bureau,Shaanxi Province(No.2020KJRC0049)。
文摘A manufacturing method is proposed for carbon based composite double polymer compliant electrode.The stiffness of this compliant electrode is changed by adjusting the mass fraction of carbon black and the ratios between Ecoflex20 and RT625.Tensile machine is used to test its ductility and hardness.The conductivity is measured through the source table.Finally,it is printed on the dielectric elastomers(DE)film,and the high-voltage amplifier is used for dielectric elastomers actuators(DEAs)dynamics testing.The results show that the compliant electrode has high tensile properties(>200%),low stiffness(<300 kPa)and well conductivity(0.0493 S/cm).It is proved that the DEAs displacement output is up to 1.189 mm by this compliant electrode under dynamic response,which is 1.64 times and 1.32 times of the same type.Moreover,this formula extends the curing time of the original compliant electrode ink.It can provide a reference for the production of compliant electrode and DEAs in the future.
文摘In this paper, the tensile properties of the MWK structures produced with different basic stitches for composite reinforcement were experimentally studied. The results show that the MWK structures with the double loop pillar stitches have better mechanical properties.
基金Project(20806035)supported by the National Natural Science Foundation of ChinaProject(2009CI026)supported by the Back-up Personnel Foundation of Academic and Technology Leaders of Yunnan Province,ChinaProject(KKZ6200927001)supported by the Opening Fund of Key Laboratory of Inorganic Coating Materials,Chinese Academy of Sciences
文摘Ni-W-P composite coatings reinforced by Ce O2 and Si O2 nano-particles on the surface of common carbon steels, were prepared by double pulse electrodeposition. The crystallization course was characterized by phase structures, crystallinity, grain sizes and microstructures. The results indicate that as-deposited composite coating is amorphous. Whereas it turns into the crystalline structure with 98.25% crystallinity, and Ni3 P, Ni2 P and Ni5P2 alloy phases precipitate from structures at 400 °C. Thereafter, Ni2 P and Ni5P2 metastable alloy phases turn into Ni3 P stable alloy phase at 500 °C. The crystallization course of the composite coating has finished when being heat-treated at 700 °C. The average sizes of Ni grains increase with the rise of heat treatment temperature from400 °C to 700 °C. Ce O2 and Si O2 nano-particles deposited into Ni-W-P alloys can delay the crystallization course and habit the growth of alloy phases.
文摘In order to investigate the damage characteristic of ceramic-metal interpenetrating phase composite（IPC） under dynamic loading, uniaxial dynamic compression was performed to characterize the failure of SiC/Al composite with 15% porosity using a modifi ed Split Hopkinson Pressure Bar（SHPB）. High speed photography was used to capture the failure procedure and set up the relationship between deformation and real stress. The deformation control technology was used to obtain collected samples in different deformations under dynamic loading. Micro CT technology was utilized to acquire real damage distribution of these specimens. Moreover, SEM was employed in comparing the damage characteristics in IPC. A summary of the available experimental results showed that IPC without lateral confi nement formed double cones. The different features compared with ceramic materials without restraint was shown to be the result of the lateral restraint effect provided by metal phase to ceramics skeleton.
基金supported by the National Natural Science Foundation of China[grant number 51772151,51761145103]the Nanjing University of Aeronautics and Astronautics PhD short-term visiting scholar project([2018]47)[grant number 190105DF06]the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘A double network nested foam composite with tunable electromagnetic wave absorption performance was fabricated via a carbonization,impregnation,and chemical vapor infiltration method.The research results indicated that the three-dimensional interconnected carbon foam was successfully enhanced by the SiC nanowire network.As expected,the electromagnetic absorption performance of the as-prepared SiC nanowire reinforced carbon foam(SiC_(nw)/CF)was greatly improved by the introduction of the SiC nanowires.The SiC_(nw)/CF composite prepared with a lower concentration of Ni catalyst possessed an excellent microwave absorption property with the lowest reflection loss value of-36.31 dB with a matched thickness of 2.60 mm accompanied by the widest effective bandwidth of 4.52 dB.An increase in catalyst concentration degraded the electromagnetic absorption ability to a certain extent.A potential microwave absorption schematic diagram was finally proposed,and it stated that the SiC nanowire network played an essential role in the improvement of the electromagnetic absorption properties.
基金National Key Research and Development Program of China(2023YFB2503900)National Natural Science Foundation of China(22505091)+3 种基金Hubei Science and Technology Program(ZYYD202400156,JSCX202500431)China Postdoctoral Science Foundation(2024M761176)Postdoctoral Fellowship Program of CPSF(GZC20250099)Postdoctor Project of Hubei Province(2024HBBHJD056)。
文摘Halide solid state electrolytes(SSEs)have attracted significant attention due to their outstanding advantages of better cathodic stability and higher ionic conductivity.However,the most halide SSEs are unstable against lithium,preventing their direct use with lithium anodes and thus sacrificing the energy density of all solid-state lithium batteries(AsSLBs),which significantly limits their application.Conventional strategies,such as employing Li-In anode or sulfide interface layer,suffer from reduced energy density or interfacial incompatibility.Employing a halide of the same family as the interface layer,instead of the chemically dissimilar sulfide SSEs,is expected to resolve the interfacial compatibility problem.Herein,we propose an all-halide double composite electrolyte(LTLC-LZC),where Li_(2)ZrCl_(6)(LZC)serves as the bulk layer and Li_(0.388)Ta_(0.238)La_(0.475)Cl_(3)(LTLC)functions as the anode-side interfacial contact layer.The two halide electrolytes exhibit excellent chemical compatibility and comparable processability,enabling facile cold-pressed bilayer assembly.Compared with single-layer LZC,the LTLC-LZC electrolyte significantly enhances interfacial stability and ionic conductivity.Therefore,Li|LTLC-LZC|Li symmetric cells cycle stably for over 2500 h,while Li|LTLC-LZC|NCM622 full cells deliver high initial coulombic efficiency and maintain~100%coulombic efficiency during cycling.This work provides a viable pathway toward practical high-energy halide-based AsSLBs.
