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journal of Materials Science & Technology 2018年第7期34卷 1214-1221页

作者： Y.K.Zhu Q.Y.Chen Q.Wang H.Y.Yu R.Li j.p.Hou Z.j.Zhang G.p.Zhang Z.f.Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences National Quality Supervision & Inspection Center of Electrical Equipment Safety performance Zhejiang Huadian Equipment Testing Institute

The evolution of microstructure in the drawing process of commercially pure aluminum wire （CpAW） does not only depend on the nature of materials, but also on the stress profile. In this study, the effect of stress profile on the texture evolution of the CpAW was systematically investigated by combining the numerical simulation and the microstructure observation. The results show that the tensile stress at the wire center promotes the formation of 〈111〉 texture, whereas the shear stress nearby the rim makes little contribution to the texture formation. Therefore, the 〈111 〉 texture at the wire center is stronger than that in the surface layer, which also results in a higher microhardness at the center of the CpAW under axial loading.2017 published by Elsevier Ltd on behalf of The editorial office of journal of Materials Science ＆ Technology.

关键词： Commercially pure aluminum wire Cold drawing Texture finite element simulation Stress profile

Molecular beam epitaxy growth of monolayer hexagonal MnTe_(2)on Si(111)substrate

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Chinese physics B 2021年第12期30卷 142-147页

作者： S Lu K peng p D Wang A X Chen W Ren X W fang Y Wu Z Y Li H f Li f Y Cheng K L Xiong j Y Yang j Z Wang S A Ding Y p jiang) L Wang Q Li f S Li L f Chi Institute of functional Nano&Soft Materials(fUNSOM) Soochow UniversitySuzhou 215123China Vacuum Interconnected Nanotech Workstation(Nano-X) Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of Sciences(CAS)Suzhou 215123China Key Laboratory of polar Materials and Devices(MOE) Department of ElectronicSchool of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China School of physical Science and Technology Southwest UniversityChongqing 400715China School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China

Monolayer MnTe_(2)stabilized as 1 T structure has been theoretically predicted to be a two-dimensional(2 D)ferromagnetic metal and can be tuned via strain *** is no naturally van der Waals(vdW)layered MnTe_(2)bulk,leaving mechanical exfoliation impossible to prepare monolayer MnTe_(2).Herein,by means of molecular beam epitaxy(MBE),we successfully prepared monolayer hexagonal MnTe_(2)on Si(111)under Te rich *** reflection high-energy electron diffraction(RHEED)and low-energy electron diffraction(LEED)patterns suggest the monolayer is atomically flat without surface *** valence state of Mn^(4+)and the atom ratio of([Te]:[Mn])further confirm the MnTe_(2)*** tunneling spectroscopy(STS)shows the hexagonal MnTe_(2)monolayer is a semiconductor with a large bandgap of~2.78 *** valence-band maximum(VBM)locates at theΓpoint,as illustrated by angle-resolved photoemission spectroscopy(ARpES),below which three hole-type bands with parabolic dispersion can be *** successful synthesis of monolayer MnTe_(2)film provides a new platform to investigate the 2D magnetism.

关键词： molecular beam epitaxy hexagonal MnTe_(2) band structure

Experimentally validated atomistic simulation of the effect of relevant grinding parameters on work piece topography,internal stresses,and microstructure

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friction 2022年第4期10卷 608-629页

作者： S.j.EDER p.G.GRÜTZMACHER T.SpENGER H.HECKES H.ROjACZ A.NEVOSAD f.HAAS AC2T research GmbH Viktor-Kaplan-Straße 2/CWiener Neustadt 2700Austria Institute of Engineering Design and product Development TU WienLehárgasse 6-Objekt 7Vienna 1060Austria Institute of production Engineering Graz University of TechnologyKopernikusgasse 24/IGraz 8010Austria Tyrolit-Schleifmittelwerke Swarovski K.G. Swarovskistraße 33Schwaz 6130Austria

In this work,we present a fully atomistic approach to modeling a finishing process with the goal to shed light on aspects of work piece development on the microscopic scale,which are difficult or even impossible to observe in experiments,but highly relevant for the resulting material *** a large-scale simulative parametric study,we varied four of the most relevant grinding parameters:The work piece material,the abrasive shape,the temperature,and the infeed *** order to validate our model,we compared the normalized surface roughness,the power spectral densities,the steady-state contact stresses,and the microstructure with proportionally scaled macroscopic experimental *** the grain sizes vary by a factor of more than 1,000 between experiment and simulation,the characteristic process parameters were reasonably reproduced,to some extent even allowing predictions of surface quality degradation due to tool *** the experimentally validated model,we studied time-resolved stress profiles within the ferrite/steel work piece as well as maps of the microstructural changes occurring in the near-surface *** found that blunt abrasives combined with elevated temperatures have the greatest and most complex impact on near-surface microstructure and stresses,as multiple processes are in mutual competition here.

关键词： large-scale molecular dynamics surface quality microstructure Revolutions per minute-Synchronous Grinding(RpM-Synchronous Grinding) tool wear

Oxidation performance and Interdiffusion Behaviour of two MCrAlY Coatings on a fourth-Generation Single-Crystal Superalloy

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Acta Metallurgica Sinica(English Letters) 2022年第4期35卷 679-692页

作者： K.j.Tan j.j.Liang X.G.Wang X.p.Tao j.Gong C.Sun Y.Z.Zhou X.f.Sun Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The oxidation behaviour of a fourth-generation single-crystal superalloy without coating and with two types of MCrAlY coatings at 1140℃was *** results showed that both coatings greatly improved the oxidation resistance of the superalloy,and the addition of Hf further improved the oxidation resistance by pinning the oxide layer into the *** and after oxidation,obvious Cr and Al interdiffusion was *** Cr diffusion induces the precipitation of a topologically close-packed phase,while the diffusion of Al affects the structure of theγ/γ’phase,the solubility of refractory elements,and the formation of an interdiffusion zone.

关键词： Superalloys Metal coatings Oxidation Electron probe microanalyser(EpMA) Element diffusion

Graphene's photonic and optoelectronic properties——A review

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Chinese physics B 2020年第3期29卷 13-35页

作者： A j Wirth-Lima p p Alves-Sousa W Bezerra-fraga Department of physics Federal Institute of EducationScience and Technology of Ceara Campus SobralCearaBrazil postgraduate program in Electrical Engineering and Computing federal University of Ceara(U.f.C.)Sobral CearaBrazil

Due to its remarkable electrical and optical properties,graphene continues to receive more and more attention from researchers around the *** excellent advantage of graphene is the possibility of controlling its charge density,and consequently,the management of its conductivity and dielectric constant,among other *** is noteworthy that the control of these properties enables the obtaining of new optical/electronic devices,which would not exist based on conventional ***,to work in this area of science,it is necessary to have a thorough knowledge regarding the electrical/optical properties of *** this review paper,we show these graphene properties very well detailed.

关键词： absorbance conductivity dielecric constant dispersion relation

Design and optimization of the composition and mechanical properties for non-equiatomic CoCrNi medium-entropy alloys

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journal of Materials Science & Technology 2023年第8期139卷 232-244页

作者： j.X.Yan Z.j.Zhang p.Zhang j.H.Liu H.Yu Q.M.Hu j.B.Yang Z.f.Zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China chool of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China School of Information Science and Engineering Shenyang University of TechnologyShenyang 111003China

The development of multi-principal element alloys(MpEAs,also called as high-or medium-entropy al-loys,HEAs/MEAs)provides tremendous possibilities for materials ***,designing MpEAs with desirable mechanical properties confronts great challenges due to their vast composition *** this work,we provide an essential criterion to efficiently screen the CoCrNi MEAs with outstanding strength-ductility *** negative Gibbs free energy difference△E_(fCC-BCC)between the face-centered cubic(fCC)and body-centered cubic(BCC)phases,the enhancement of shear modulus G and the decline of stacking fault energy(SfE)γ_(isf)are combined as three requisites to improve the fCC phase stability,yield strength,deformation mechanisms,work-hardening ability and ductility in the *** effects of chemical composition on△E_(fCC-BCC),G andγisf were investigated with the first principles calculations for Co_(x)Cr_(33)Ni_(67-x),Co_(33)Cr_(y)Ni_(67-y)and Co_(z)Cr_(66-z)Ni_(34)(0≤x,y≤67 and 0≤z≤66)*** on the essential criterion and the calculation results,the composition space that displays the neg-ative Gibbs free energy difference△E_(fCC-BCC),highest shear modulus G and lowest SfEγ_(isf)was screened with the target on the combination of high strength and excellent *** this context,the optimal composition space of Co-Cr-Ni alloys was predicted as 60 at.%-67 at.%Co,30 at.%-35 at.%Cr and 0 at.%-6 at.%Ni,which coincides well with the previous experimental evidence for Co_(55)Cr_(40)Ni_(5)*** valid-ity of essential criterion is further proved after systematic comparison with numerous experimental data,which demonstrates that the essential criterion can provide significant guidance for the quick exploitation of strong and ductile MEAs and promote the development and application of MpEAs.

关键词： Medium-entropy alloys first-principles calculations phase stability Stacking-fault energy Strength Ductility

Improving weld formability by a novel dual-rotation bobbin tool friction stir welding

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journal of Materials Science & Technology 2018年第1期34卷 135-139页

作者： f.f.Wang W.Y.Li j.Shen Q.Wen j.f.dos Santos State Key Laboratory of Solidification processing Shaanxi Key Laboratory of Friction Welding Technologies Northwestern Polytechnical University Helmholtz-Zentrum Geesthacht Institute of Materials Research Materials Mechanics China Academy of Launch Vehicle Technology Beijing Institute of Astronautical Systems Engineering

A novel dual-rotation bobbin tool friction stir welding （DBT-fSW） was developed, in which the upper shoulder （US） and lower shoulder （LS） have different rotational speeds. This process was tried to weld 3.2 mm thick alunlinum-lithium alloy sheets. The metallographic analysis and torque measurement were carried out to characterize the weld formabiliW. Experimental results show that compared to conven- tional bobbin tool friction stir welding, the DBT-fSW has an excellent process stability, and can produce the defect-free joints in a wider range of welding parameters. These can be attributed to the significant improvement of material flow caused by the formation of a staggered layer structure and the unbalanced force between the US and LS during the DBT-fSW process.

关键词： Bobbin tool friction stir welding Dual rotation Material flow Microstructure Microhardness

两类层次模糊Mass-Assignment系统是全局逼近器(英文)

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软件学报 2002年第10期13卷 1943-1951页

作者：王士同 j.f.Baldwin T.p.Martin 英国Bristol大学先进计算研究中心

基于mass assignment 理论,提出了两类层次模糊mass assignment系统,并运用构造性证明过程证明了其全局逼近性质.由于类型1层次模糊系统的规则数与输入变量数呈线性关系,类型2层次模糊系统按逼近精度要求引入子模糊系统,因此,此两类层... 详细信息

基于mass assignment 理论,提出了两类层次模糊mass assignment系统,并运用构造性证明过程证明了其全局逼近性质.由于类型1层次模糊系统的规则数与输入变量数呈线性关系,类型2层次模糊系统按逼近精度要求引入子模糊系统,因此,此两类层次模糊mass assignment系统可被用来有效地克服模糊规则爆炸问题,即所谓的规则数与输入变量数呈指数关系问题.

关键词：层次模糊Mass-Assignment系统全局逼近器人工智 mass-assignment理论

Numerical analysis of high‑speed railway slab tracks using calibrated and validated 3D time‑domain modelling

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Railway Engineering Science 2024年第1期32卷 36-58页

作者： A.f.Esen O.Laghrouche p.K.Woodward D.Medina‑pineda Q.Corbisez j.Y.Shih D.p.Connolly Institute for High‑Speed Rail and System Integration University of LeedsLeeds LS29JTUK Institute for Infrastructure and Environment Heriot-Watt UniversityEdinburgh EH144ASUK Alstom Transport Saint‑OuenFrance Birmingham Centre for Railway Research and Education University of BirminghamBirmingham B152TTUK

Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance *** this paper,the elastic performance of a novel slab trackform for high-speed railways is investigated using three-dimensional finite element modelling in *** is then compared to the performance of a ballasted ***,slab and ballasted track models are developed to replicate the full-scale testing of track *** the models are calibrated with the experimental results,the novel slab model is developed and compared against the calibrated slab track *** slab and ballasted track models are then extended to create linear dynamic models,considering the track geodynamics,and simulating train passages at various speeds,for which the Ledsgard documented case was used to validate the *** travelling at low and high speeds are analysed to investigate the track deflections and the wave propagation in the soil,considering the issues associated with critical *** train loading methods are discussed,and the most practical approach is retained and ***,correlations are made between the geotechnical parameters of modern high-speed rail and conventional *** is found that considering the same ground condition,the slab track deflections are considerably smaller than those of the ballasted track at high speeds,while they show similar behaviour at low speeds.

关键词： High-speed railways Slab track New ballastless track Ballasted track Critical speeds finite element modelling Calibration of numerical models

Recent progresses on designing and manufacturing of bulk refractory alloys with high performances based on controlling interfaces

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journal of Materials Science & Technology 2020年第17期52卷 29-62页

作者： T.Zhang H.W.Deng Z.M.Xie R.Liu j.f.Yang C.S.Liu X.p.Wang Q.f.fang Y.Xiong School of physics and Electronic Engineering Guangzhou UniversityGuangZhou 510006China Key Laboratory of Materials physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China State Key Laboratory of Environment friendly Energy Materials West South University of Sciences and TechnologyMianYang 621010China

Refractory alloys such as tungsten and molybdenum based alloys with high strength,thermal/electrical conductivity,low coefficient of thermal expansion and excellent creep resistances are highly desirable for applications in nuclear facilities,critical components in aerospace and defense ***,the serious embrittlement limits the engineering usability of some refractory alloys.A lot of research results indicate that the performances of refractory alloys are closely related to the physical/chemical status,such as the interface dimension,interface type,interface composition of their grain boundaries(GBs),phase boundaries(pBs)and other interface *** paper reviewed the recent progress of simulations and experiments on interface design strategies that achieve high performance refractory *** strategies include GB interface purifying/strengthening,pB interface strengthening and pB/GB synergistic *** details are provided on the design/fabrication strategy such as GB interface controlling,pB interface controlling and synergistic control of multi-scaled *** corresponding performances such as the mechanical property,thermal conductivity,thermal load resistance,thermal stability,irradiation resistance,and oxidation resistance are reviewed in the aspect to the effect of *** addition,the relationships between these interfaces and material properties are ***,future developments and potential new research directions for refractory alloys are proposed.

关键词： Interface controlling Designing and manufacturing Refractory alloys Structure and performance