检索结果-南通市图书馆

Composition and size dependent torsion fracture of metallic glasses

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第23期82卷 153-160页

作者： J.Dong J.Shen y.h.sun h.B.Ke B.A.sun W.h.Wang h.y.Bai Institute of Physics Chinese Academy of SciencesBeijing100190PR China College of Materials Science and Opto Electronic Technology University of Chinese Academy of SciencesBeijing100049PR China Songshan Lake Materials Laboratory DongguanGuangdong523808PR China

The fracture of metallic glasses(MGs)of different compositions and sizes down to micrometers under torsion loading were systematically *** to the flat shear fracture along the circumferential plane as commonly supposed under torsion,we find that the torsion fracture of metallic glasses can deviate from flat shear plane,and the fracture angle is closely dependent on the composition and the size of MG *** a conversion method,we show that the torsion fracture of both millimeterand micrometer-sized MGs can be described by the ellipse fracture criterion as originally proposed for the tension *** deviation from the circumferential shear plane under torsion is further shown to intrinsically relate to the fracture toughness of *** tougher MG tends to have a smaller fracture angle with respect to the maximum shear plane,and vice versa,indicating a correlation between the fracture toughness and pressure/normal stress sensitivity in *** results provide new insights on the fracture mechanism and are helpful to design and control the deformation and fracture behavior of MGs under torsion loading.

关键词： Metallic glasses Torsion fracture Pressure sensitivity Fracture toughness

Rotational and translational domains of beta precipitate in aged binary Mg-Ce alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2021年第3期9卷 1039-1056页

作者： B.Z.sun h.X.Zhang y.Dong J.X.Ren y.Tian G.M.Xie J.Tan y.h.sun Na Xiao School of Materials Science and Engineering Northeastern UniversityShenyang 110819China State Key Lab Rolling&Automat Northeastern UniversityShenyang 110819China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Analytical and Testing Center Northeastern UniversityShenyang 110819China

The structural evolution fromβ_(1)(Mg_(3)Ce)toβ(Mg_(12)Ce)precipitates,which takes place at the over-aged stage of binary Mg-Ce alloys,are investigated by high-angle annular dark-field scanning transmission electron *** structural transformation mainly occurs in the{111}_(β1)crystallographic planes,where the newly formedβlattices exhibit two categories of domain structures,namely rotational and translational *** rotational domain is composed of threeβdomains(β_(RA),β_(RB)andβ_(RC)),which are related by a 120°rotation with respect to each other around the 111_(β1)axis of theirβ_(1)parent ***{111}_(β1)crystallographic planes can provide four sets of sublattices with the same orientation for an initial nucleation ofβ*** leads to the formation of four translationalβdomains(β_(TA),β_(TB),β_(TC)andβ_(TD)),among which any two differ by a vector of 1/6112_(β1).We deduce theoretically that there exist twenty-fourβdomains during this ***,considering the interfacial misfit,only one-third of domains can grow up and eventually formsβ***,a majority ofβribbons overlap partiallyβ_(1)plate,which is beneficial to relax interfacial strain amongβ,β_(1)andα-Mg matrix(α/β/β_(1)).The configuration of multipleβdomains can effectively regulate interfacial misfit ofα/βandβ/β_(1),which are responsible for enhancing the hardness and strength of Mg-Ce ***,this study aims to provide some clues to improve the over-aged performance of magnesium alloys by constructingβdomains and optimizing theα/β/β_(1)interface.

关键词： Magnesium alloys hAADF-STEM Rotational domain Translational domain Phase transition Interfacial misfit

A negative deviation from Porod’s law in SAXS of organo—MSU—X

在线全文

学校读者我要写书评

暂无评论

Beijing Synchrotron Radiation Facility 2001年第2期 20-25页

作者： Z.h.Li y.J.Gong D.Wu y.h.sun J.Wang y.Liu B.Z.Dong y.J. LaboratoryofSynchrotronRadiation InstituteofHighEnergyPhysicschineseAcademyofSciencesP.O.Box165Beijing100039People’sRepublicofchina StateKeyLaboratoryofCoalConverison InstituteofCoalChemistryChi

Small-angle X-ray scattering(SAXS)using synchrotron radiation as X-ray source has been employed to charactcizc the microscopic structrure of organo-modified mesoporous molecular sieves(organo-MSU-X)prepared by a one-pot template-directed *** is shown that the SAXS profile is hardly constant with Porod’s law showing a negative slope,i.e.,negative *** suggests that there is diffuse interfacial layer located between the pores and the *** suggests that the organic groups remain covalently linked to the matrix,as indicated by ^29SiCP MAS NMR and *** average thickness of the interfacial layer was found to be about 1nm for each of the three samples with different kinds and the same amounts(20? of organic *** kind of material has also been proved to possess both surface and mass fractal structure of the amophous porous silica materials.2001 Elsevier Science *** rights reserved.

关键词：中孔材料 SAXS 小角X射线散射分析界面层结构特征有机中孔分子筛负偏差 Porod法

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

湿气条件下的管道腐蚀

国外油田工程 2002年第8期18卷 46-47,54页

作者： y.h.sun 郑君黄红兵中国石油西南油气田分公司天然气研究院

在压力小于 1 82MPa、温度为 4 0℃时 ,测量了 10cm管径高压管道顶部和底部的二氧化碳(CO2 )湿气腐蚀速率。在气体流速小于 11m s和液体流速小于 0 2m s时 ,测定其流型。介质为去离子水和CO2 气体。在试验条件下的流型为环型或接近... 详细信息

在压力小于 1 82MPa、温度为 4 0℃时 ,测量了 10cm管径高压管道顶部和底部的二氧化碳(CO2 )湿气腐蚀速率。在气体流速小于 11m s和液体流速小于 0 2m s时 ,测定其流型。介质为去离子水和CO2 气体。在试验条件下的流型为环型或接近层状环流过渡区。在 3h后腐蚀速率趋于稳定且随气体流速、液体流速和CO2 分压的增加而增长。试验结果可应用于油田条件。

关键词：湿气条件管道腐蚀油气管道二氧化碳腐蚀速率

In situ polymerization of poly(3,4-ethylenedioxythiophene)protective layer towards stable zinc anode

在线全文

学校读者我要写书评

暂无评论

Nano Research 2025年第1期18卷 382-394页

作者： Debin Luo Peng Zhou Xiaowei Lv Panpan sun Xiaohua sun hewei Zhao College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China hubei Three Gorges Laboratory Yichang 443007China School of Chemistry Beihang UniversityBeijing 100191China

Aqueous zinc-ion devices are considered promising candidates for energy storage due to their high safety,low cost and relatively high energy ***,the dendrite growth,hydrogen evolution reaction(hER)and corrosion of the zinc anode significantly limit the development of Zn-ion ***,an inexpensive poly(3,4-ethylenedioxythiophene)(PEDOT)protective layer was constructed in situ on the Zn surface using electropolymerization to suppress dendrite growth and side reactions,thereby enhancing the reversibility of *** and theoretical calculations revealed that this hydrophilic protective layer promotes the desolvation process of hydrated Zn^(2+)and facilitates the transport of zinc ions,thus improving the thermodynamic and kinetic properties of Zn^(2+)deposition and inhibiting interfacial side ***,the optimized PEDOT@Zn symmetric battery exhibited a cycling stability exceeding 1250 h at 0.5 mA·cm^(-2)and 0.25 mAh·cm^(-2),with a significantly reduced overpotential(from 91.8 to 35 mV).With the assistance of the PEDOT protective layer,the PEDOT@Zn//Cu battery maintained approximately 99.5%Coulombic efficiency after 450 ***-situ scanning electron microscopy(SEM)and in situ optical microscopy characterizations further confirmed that the PEDOT protective layer can effectively suppress the growth of zinc ***,the Zn-ion capacitors assembled by the PEDOT@Zn and activated carbon also demonstrated outstanding cycling stability.

关键词： zinc-ion devices zinc anode poly(3 4-ethylenedioxythiophene)(PEDOT) dendrite desolvation process

Friction stir spot welding of SPCC low carbon steel plates at extremely low welding temperature

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2019年第5期35卷 733-741页

作者： y.F.sun h.Fujii y.Sato y.Morisada Joining and Welding Research Institute Osaka University 11-1 Mihogaoka Ibaraki 567-004Japan School of Materials Science and Engineering Zhengzhou University Zhengzhou 450001 China

Friction stir spot welding (FSSW) was applied to 2.0 mm thick steel plate cold-rolled commercial (SPCC) low carbon steel plates at a very low rotation speed that ranged from 5 to 50rpm, which was much lower than that generally used for the conventional FSSW technique. Due to the very low heat input, the welding processes could therefore be completed at a peak welding temperature below 160℃. As a result, a significantly refined microstructure with an average grain size of about 0.41μm was formed in the stir zone of the joints and the JI {0-11 } and J2{1-1O} shear textures were the dominant components, which are different from the D1{11-2} and D2{-1-12} shear textures formed in the conventional FSSW joints. In addition, no heat affected zone could be detected along the crosssectional plane of the joints. Although a few void-like non-bonded areas were still observed along the interface between the upper and lower steel plates, the shear tensile loads of the joints increased to about 10.0 kN when welded at a condition of 8t, 20rpm and 30 s, and the joints fractured through the plug failure mode.

关键词： Friction stir spot welding Dynamic recrystallization Microstructure Steel

Effect of post-bond heat treatment on the microstructure and high temperature mechanical property of a TLP bonded γ'-strengthened co-based single crystal superalloy

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第21期80卷 244-258页

作者： S.y.Wang y.sun C.y.Cui X.F.sun y.Z Zhou y.M.Ma h.L.An Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China harbin Welding Institute China Academy of Machinery Science and TechnologyHarbin 150028China

Post-bond heat treatment(PBhT) applied to a transient liquid phase(TLP) bonding joint is an effective approach to remove the brittle borides and improve its ***,we proposed two types of PBhT strategies to obtain a TLP bonded γ'-strengthened Co-based single crystal superalloy,and the microstructural characteristics and tensile properties of the two heat treated joints were compared to identify the optimal PBhT *** evolution of the brittle boride in the joint after the PBhT was studied by using in-situ *** experimental results allowed to provide a theoretic model to quantitatively evaluate the distribution of the brittle phase after the optimal PBhT and analyze the joint fractures to understand the failure *** obtained results revealed that a post-bond solid solution treatment performed to the joint at a high temperature(over 1275℃) could decrease the area fraction of the boride from 7.2 % to 1.4 % and increase the elongation from 1.9 % to 7.8 %.This work emphasizes the relevance of solid solution temperature when a PBhT strategy is applied.

关键词： Transient liquid phase(TLP) γ'-strengthened co-based single crystal superalloy heat treatment sequence Brittle boride Tensile property

Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu Zhao hang Ma Conghui Zhang yongxin yang Shuyuan yu haiye Zhu yongjiang sun hong Guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China yunnan yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer *** other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery

IMPROVED METhOD OF PARTIAL SIMILARITy OF BOUNDARy LAyER ALONG CURVED SURFACE

在线全文

学校读者我要写书评

暂无评论

Journal of hydrodynamics 2001年第2期13卷 77-79页

作者： sun, F.Z. Shi, y.T. sun, h.J. Ping, y.M. Zhang, M.y. Inst. of Energy and Power Shandong Univ. Jinan 250061 China

The solution of boundary layer along a curved surface was discussed in this article. According to the principle of the theory of similarity, the method of partial similarity was proposed, in which the profile of object is divided into many tiny sections, the method of similarity was used in each section and the error in each section was fully considered. This method is proved to be feasible.

关键词： Cylinders (shapes) Differential equations Error analysis Surfaces