Heat-resistant aluminum alloys are widely used in aerospace and automotive fields for manufacturing hot components due to their advantages in lightweight design and energy ***,the high-temperature strength of existing...
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Heat-resistant aluminum alloys are widely used in aerospace and automotive fields for manufacturing hot components due to their advantages in lightweight design and energy ***,the high-temperature strength of existing cast aluminum alloys is always limited to about 100 MPa at 350℃due to coarsening and transformation of strengthening ***,we reveal that the yield strength and ultimate tensile strength of the T6 state Al-8.4Cu-2.3Ce-1.0Mn-0.5Ni-0.2Zr alloy at 400◦C increase by 34%and 44%after re-aging at 300℃for 100 h,and its thermal strength exhibits distinguished ad-vantage over traditional heat-resistant aluminum *** enhanced elevated-temperature strength is attributed to the reprecipitation of the Ni-bearing T-Al_(20)Cu_(2)Mn_(3)phase,whose number density increases over one *** significant segregation of Ni,Ce,and Zr elements at the interfaces helps improve the thermal stability of the T *** thermostable T phase effectively strengthens the matrix by in-hibiting dislocation ***,a highly interconnected 3D intermetallic network along the grain boundaries can still remain after long-term re-aging at 300℃,which is conducive to imposing a drag on the grain boundaries at high *** finding offers a viable route for enhancing the elevated-temperature strength of heat-resistant aluminum alloys,which could provide expanded opportunities for higher-temperature applications.
The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering *** a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and farsid...
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The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering *** a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and farside scattering *** contrast,the envelope method can decompose the experimental data into two components with negative and positive deflection angles,***,a question arises as to whether the comparison between the calculated nearside(or farside)component and the derived positive-deflection-angle(or negative-deflection-angle)component can help analyze the potential ambiguity *** this study,we conducted a trial application of the envelope method to the potential ambiguity *** envelope method was improved by including uncertainties in the experimental *** colliding systems of 16O+28Si at 215.2 MeV and 12C+12C at 1016 MeV were considered in the *** each colliding system,the angular distribution experimental data were described nearly equally well by two potential sets,one of which is“surface transpar-ent”and the other is *** calculated angular distributions were decomposed into nearside and farside scattering *** the improved envelope method,the experimental data were decomposed into the positive-deflection-angle and negative-deflection-angle components,which were then compared with the calculated nearside and farside *** capability of the envelope method to analyze the potential ambiguities was also discussed.
The residual stress field induced by surface strengthening processes such as mechanical shot peening and other forms of plastic deformation does not generally exhibit a simple"monotonic"distribution *** rese...
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The residual stress field induced by surface strengthening processes such as mechanical shot peening and other forms of plastic deformation does not generally exhibit a simple"monotonic"distribution *** researchers have analyzed this fact from a mechanical perspective based on Hertz ***,the micro/nano-scale microstructural changes corresponding to the distribution of residual stress fields still appear to be *** this study,we focused on a widely used material in aviation manufacturing,namely nickel-based superalloy GH4169,as our experimental *** subjected GH4169 alloy to me-chanical strengthening treatment using a shot peening intensity of 0.25 mmA,followed by quantitative testing of micromechanical performance indicators such as microhardness and residual *** thor-oughly investigate the relationship between micromechanical properties and microstructure changes,we utilized transmission electron microscopy(TEM)to observe and analyze shot-peened materials at differ-ent *** findings revealed that the most severe microstructural distortion induced by mechanical shot peening in GH4169 alloy was likely to occur within a depth range of 25 to 75 *** observation aligns with the actual phenomenon that the maximum microhardness and maximum residual compres-sive stress did not manifest on the outermost surface of the *** presenting a detailed analysis of deformation defects such as dislocations,stacking faults,and twinning in different depths of mechan-ically strengthened layers,our study contributes to a deeper understanding and practical application of post-processing technologies based on plastic deformation.
The flourish of deep learning frameworks and hardware platforms has been demanding an efficient compiler that can shield the diversity in both software and hardware in order to provide application *** the existing dee...
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The flourish of deep learning frameworks and hardware platforms has been demanding an efficient compiler that can shield the diversity in both software and hardware in order to provide application *** the existing deep learning compilers,TVM is well known for its efficiency in code generation and optimization across diverse hardware *** the meanwhile,the Sunway many-core processor renders itself as a competitive candidate for its attractive computational power in both scientific computing and deep learning *** paper combines the trends in these two ***,we propose swTVM that extends the original TVM to support ahead-of-time compilation for architecture requiring cross-compilation such as *** addition,we leverage the architecture features during the compilation such as core group for massive parallelism,DMA for high bandwidth memory transfer and local device memory for data locality,in order to generate efficient codes for deep learning workloads on *** experiment results show that the codes generated by swTVM achieve 1.79x improvement of inference latency on average compared to the state-of-the-art deep learning framework on Sunway,across eight representative *** work is the first attempt from the compiler perspective to bridge the gap of deep learning and Sunway processor particularly with productivity and efficiency in *** believe this work will encourage more people to embrace the power of deep learning and Sunwaymany-coreprocessor.
Creep rupture of the reduced activation ferritic/martensitic(RAFM)steel and 316L steel dissimilar joint by friction stir welding was *** creep rupture time of the dissimilar joint was 1941 h at 600℃/100 MPa and 120 h...
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Creep rupture of the reduced activation ferritic/martensitic(RAFM)steel and 316L steel dissimilar joint by friction stir welding was *** creep rupture time of the dissimilar joint was 1941 h at 600℃/100 MPa and 120 h at 650℃/100 *** creep fracture occurred in heat affect zone(HAZ)of RAFM steel side where coarse Laves phase was *** formation and coarsening of the Laves phase particles in HAZ of RAFM steel side were the main reasons that caused the creep fracture of the dissimilar *** Laves phase particles nucleated adjacent to the large M_(23)C_(6) particles at the grain boundaries where W element segregated and grew fast during creep *** large Laves phase would deteriorate the pinning effect of M_(23)C_(6) carbides and weaken the solid solution strengthening ***,the size of the Laves phase in HAZ of RAFM steel side was bigger than that in stir zone of RAFM steel *** reasons explain the creep fracture in HAZ of RAFM steel side of dissimilar joint.
Silicon(Si)has emerged as a promising anode material for lithium-ion batteries(LIBs)due to its extremely high theoretical capacity of 4200 mAh·g^(-1).However,its practical application is limited by several critic...
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Silicon(Si)has emerged as a promising anode material for lithium-ion batteries(LIBs)due to its extremely high theoretical capacity of 4200 mAh·g^(-1).However,its practical application is limited by several critical challenges,including severe volume expansion and poor electrical ***,we employ a two-dimensional(2D)oxygen modification engineering approach to fabricate 2D oxygen-functionalized CaSi_(2)(CaSi_(2)O_(x))*** the preparation of 2D CaSi_(2) layers,O atoms are gradually incorporated onto their *** resulting 2D CaSi_(2)O_(x) layers have a thickness of 3-5 nm,closely matching the theoretical thickness of 6-10 *** used as lithium anodes,the 2D CaSi_(2)O_(x) layers exhibit exceptional electrochemical performance,maintaining stability over 3000 cycles at an ultrahigh current density of 30 A·g^(-1).By tailoring the surface properties,their pseudocapacitive charge storage mechanism is significantly enhanced,effectively overcoming the intrinsic limitations of traditional Si *** study highlights the promise of 2D surface engineering in the development of advanced materials for next-generation LIBs.
Exploring cathode materials that combine excellent cycling stability and high energy density poses a challenge to aqueous Zn-ion hybrid supercapacitors(ZHSCs).Herein,polyaniline(PANI)coated boron-carbon-nitrogen(BCN)n...
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Exploring cathode materials that combine excellent cycling stability and high energy density poses a challenge to aqueous Zn-ion hybrid supercapacitors(ZHSCs).Herein,polyaniline(PANI)coated boron-carbon-nitrogen(BCN)nanoarray on carbon cloth surface is prepared as advanced cathode materials via simple high-temperature calcination and electrochemical deposition *** of the excellent specific capacity and conductivity of PANI,the CC@BCN@PANI core-shell nanoarrays cathode shows an excellent ion storage ***,the 3D nanoarray structure can provide enough space for the volume expansion and contraction of PANI in the charging/discharging cycles,which effectively avoids the collapse of the microstructure and greatly improves the electrochemical stability of ***,the CC@BCN@PANI-based ZHSCs exhibit superior electrochemical performances showing a specific capacity of 145.8 mAh/g,a high energy density of 116.78 Wh/kg,an excellent power density of 12 kW/kg,and a capacity retention rate of 86.2%after 8000 charge/discharge cycles at a current density of 2 A/*** addition,the flexible ZHSCs(FZHSCs)also show a capacity retention rate of 87.7%at the current density of 2 A/g after 450 cycles.
The ohmic contact interface between diamond and metal is essential for the application of diamond *** modification can significantly affect the contact performance and eliminate the interface polarization ***,the radi...
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The ohmic contact interface between diamond and metal is essential for the application of diamond *** modification can significantly affect the contact performance and eliminate the interface polarization ***,the radiation stability of a diamond detector is also sensitive to surface *** this work,the influence of surface modification technology on a diamond ohmic contact under high-energy radiation was *** radiation,the specific contact resistivities(ρc)between Ti/Pt/Au-hydrogen-terminated diamond(H-diamond)and Ti/Pt/Au-oxygenterminated diamond(O-diamond)were 2.0×10^(-4)W·cm^(2) and 4.3×10^(-3)Wcm^(2),*** 10 MeV electron radiation,the ρc of Ti/Pt/Au H-diamond and Ti/Pt/Au O-diamond were 5.3×10^(-3)W·cm^(2)and 9.1×10^(-3)W·cm^(2),*** rates of change of ρc of H-diamond and O-diamond after radiation were 2550%and 112%,*** electron radiation promotes bond reconstruction of the diamond surface,resulting in an increase in ρc.
The evaporation and dilution of substrate seriously limit the performance of laser cladding coatings on magnesium *** order to overcome the above shortcomings,a multi-step ultrasonic assisted laser remelting technolog...
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The evaporation and dilution of substrate seriously limit the performance of laser cladding coatings on magnesium *** order to overcome the above shortcomings,a multi-step ultrasonic assisted laser remelting technology was proposed to improve the performance of the *** this work,a novel Cu_(2.3)Al_(1.3)Ni_(1.7)SnCr_(0.3) multi-principal element alloy coating(MPEAC)was prepared on the surface of mag-nesium *** techniques such as transmission electron microscopy(TEM),electron back scatter diffraction(EBSD)and scanning electron microscopy(SEM)were employed to characterize the microstructure and phase composition of the *** the phase structure and morphology at the interface between the coating and the substrate were also studied via focus ion beam(FIB)and TEM *** addition,the corrosion and wear resistance ability of the coatings were monitored by potentiodynamic polarization(PDP),and electrochemical impedance spectroscopy(EIS),hardness and friction *** results show that Cu_(2.3)Al_(1.3)Ni_(1.7)SnCr_(0.3) MPEAC with ultrasonic assisted is composed of FCC phase and eutectic phases(Cu_(10)Sn_(3) and Cu_(2)Ni_(3)Sn_(3)).Due to the forced convection generated by ultrasonic waves,some Cu and Ni phases are precipitated around Cu_(2)Ni_(3)Sn_(3) phases,which is beneficial to enhance the corrosion *** of the grain refinement effect caused by ultrasonic,the wear resistance of the coating is also ***,ultrasonic vibration can effectively weaken and eliminate the texture density of the Cu_(2.3)Al_(1.3)Ni_(1.7)SnCr_(0.3) MPEAC fabricated by laser cladding.
Negative stiffness (NS) structure, as a type of mechanical metamaterial, possess numerous excellent properties and has broad potential applications in areas such as impact energy absorption, vibration damping, and noi...
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