检索结果-南通市图书馆

Effect of Al_(2)O_(3)on the Mechanical Properties of(b_(4)C+Al_(2)O_(3))/Al Neutron Absorbing Materials

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： j.X.Cai b.M.Shi N.Li Y.Liu z.G.zhang Y.N.zan Q.z.Wang b.L.Xiao z.Y.Ma Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

b_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of b_(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(b_(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional b_(4)C/Al composites.

关键词： Al matrix composites Neutron absorbing materials (b_(4)C+Al_(2)O_(3))/Al composites High-temperature strength

Effect of base Material on Microstructure and Texture Evolution of a Ti–6Al–4V Electron-beam Welded joint

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

Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 499-504页

作者： G.Q.Wang z.b.zhao b.b.Yu j.R.Liu Q.j.Wang j.H.zhang R.Yang j.W.Li School of Materials Science and Engineering University of Science and Technology of China Institute of Metal Research Chinese Academy of Sciences Science and Technology on Power beam Processes Laboratory Beijing Aeronautical Manufacturing Technology Research Institute

The effect of base material（bM） on microstructure and crystallographic orientation evolution of a Ti–6Al–4V electron-beam welded joint was investigated. Meanwhile, the crystallographic orientation of prior b grains was studied by advanced electron backscattered diffraction data processing. The inhomogeneity of microstructure within welded joint was formed due to the different microstructures of bM. by comparing microstructure details of the welded joint, including microstructure morphology and crystallographic orientation with those of the base material, it can be found that both the microstructure morphology and crystallographic orientation of the EbW joint would be controlled by bM.

关键词： Electron-beam welding Titanium alloys Prior b orientation Microstructure Texture

Structural & Magnetic Characterizations of NiLizn Nanoferrites Synthesized by Co-precipitation Method

在线全文

学校读者我要写书评

暂无评论

journal of Materials Science & Technology 2011年第11期27卷 991-995页

作者： D.N. Rohadiana z.A.z. jamal S.b. jamaludin M.F. bari j. Adnan Sustainable Engineering Research Cluster Universiti Malaysia Perlis School of Microelectronic Engineering Universiti Malaysia Perlis

Synthesis of ***（0.5-x）Fe204 nanoparticles with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5 were realized via coprecipitation method. X-ray diffraction （XRD） and vibrating sample magnetometer （VSM） measurements were performed on the samples to determine the characteristics of the crystal structures and the magnetic properties of the samples, respectively. The spinel phase structures of the samples were confirmed by XRD analysis. Patterns of decreased lattice parameter and increased crystallite size values were observed by increasing the Li concentration at longer synthesis reaction periods. Similarly, for the magnetic properties, both the saturation magnetization （Ms） and coercivity （Hc） were found to vary with increasing patterns at higher Li doping levels and longer synthesis reaction periods. The results and mechanisms concerned were discussed.

关键词： Lithium nickel zinc ferrite Co-precipitation Crystal structure Magnetic properties

Magnetic and Transport Properties of Mn_(0.98)Cr_(0.02)Te Epitaxial Films Grown on Al_2O_3 Substrates

在线全文

学校读者我要写书评

暂无评论

journal of Materials Science & Technology 2014年第2期30卷 103-106页

作者： z.H.Wang D.Y.Geng j.Li Y.b.Li z.D.zhang Shenyang National Laboratory for Materials Science Institute of Metal Researchand International Centre for Materials PhysicsChinese Academy of Sciences Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences

The epitaxial Mno0.98Cr0.02Te films on single crystal Al2O3 （0001） substrates were prepared by pulsed laser deposition. The X-ray diffraction and scanning electron microscopy results showed that the good continuous epitaxial film was obtained with substrate temperature of 500 ℃. When the substrate temperature reached 700 ℃, the film was island growth and the manganese oxides phase appeared. The temperature dependence of both the magnetization and electrical resistance showed a sharp rise at around 60 K due to the magnetoelastic coupling. The temperature dependence of the electrical resistance of Mno0.98Cr0.02Te provided evidence for a transition from the metallic to semiconducting state at 305 K due to the spin disorder scattering with a large contribution from the influence of magnon drag.

关键词： Magnetic properties Mno0.98Cr0.02Te films X-ray diffraction Epitaxial film

A prediction model for the effective thermal conductivity of nanofluids considering agglomeration and the radial distribution function of nanoparticles

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2018年第3期34卷 507-514页

作者： z.M.zheng b.Wang School of Physics Sun Yat-Sen UniversityGuangzhou 510275China Instimt Franco-Chinois de l'Energie Nucleaire Sun Yat-Sen UniversityZhuhai 519000China

Conventional heat transfer fluids usually have low thermal conductivity, limiting their efficiency in many applications. Many experiments have shown that adding nanosize solid particles to conventional fluids can greatly enhance their thermal conductivity. To explain this anomalous phenomenon, many theoretical investigations have been conducted in recent years. Some of this research has indicated that the particle agglomeration effect that commonly occurs in nanofluids should play an important role in such enhancement of the thermal conductivity, while some have shown that the enhancement of the effective thermal conductivity might be accounted for by the structure of nanofluids, which can be described using the radial distribution function of particles. However, theoretical predictions from these studies are not in very good agreement with experimental results. This paper proposes a prediction model for the effective thermal conductivity of nanofluids, considering both the agglomeration effect and the radial distribution function of nanoparticles. The resulting theoretical predictions for several sets of nanofluids are highly consistent with experimental data.

关键词： Nanofluid Thermal conductivity Modeling Agglomeration Radial distribution function

Movement of tidal watersheds in the Wadden Sea and its consequences on the morphological development

在线全文

学校读者我要写书评

暂无评论

International journal of Sediment Research 2013年第2期28卷 162-171页

作者： z.b.WANG j.VROOM b.C.van PROOIjEN R.j.LAbEUR M.j.F.STIVE Delft University of Technology Faculty of Civil Engineering and Geosciences

The Wadden Sea consists of a series of tidal lagoons which are connected to the North Sea by tidal *** of each lagoon are the mainland coast,the barrier islands on both sides of the tidal inlet,and the tidal watersheds behind the two barrier *** each Wadden Island there is a tidal watershed separating two adjacent tidal *** locations of the tidal watersheds in the Wadden Sea are not *** after a human interference in one of the tidal lagoons,a tidal watershed can move and thereby influence the distribution of area between the lagoons. This appears to be important for the morphological development in not only the basin in which the interference takes place,but also in the adjacent *** paper describes theoretical analyses and numerical modelling aimed at improving the insights into the location of the tidal watersheds,their movements,and the impact of the movements of tidal watersheds on the morphological development of a multi-basin system like the Wadden Sea.

关键词： Wadden Sea Tide Tidal watershed Morphological equilibrium Sediment demand

Strain-induced formation of a gradient nanostructured surface layer on an ultrahigh strength bearing steel

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

journal of Materials Science & Technology 2018年第9期34卷 1676-1684页

作者： K.zhang z.b.Wang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

In the present work, an ultrahigh strength bearing steel（AISI 52100） was subjected to surface mechanical rolling treatment（SMRT） at room temperature. Microstructural observations showed that martensitic laths, twins and cementite particles in the initial microstructure underwent distinct plastic strains and were gradually refined into nanostructures. Consequently, a gradient nanostructured（GNS） surface layer with a mean grain size of -24 nm at the top surface was obtained on the bearing steel, resulting in an increment of -20% in the surface hardness. Analyses based on microstructural evolution, phase constitution and in-depth hardness distribution revealed a mechanically induced formation mechanism of the GNS surface layer. The multiple surface severe plastic deformation under fine lubrication and cooling during SMRT contributed to the formation of a thick hardened surface layer on the bearing steel.

关键词： Gradient nanostructured Ultrahigh strength bearing steel Plastic deformation Martensite Surface mechanical rolling treatment

Predicting the variation of stacking fault energy for binary Cu alloys by first-principles calculations

在线全文

学校读者我要写书评

暂无评论

journal of Materials Science & Technology 2020年第18期52卷 61-65页

作者： T.Cai K.Q.Li z.j.zhang P.zhang R.Liu j.b.Yang z.F.zhang Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province College of Advanced Materials and EnergyInstitute of Surface Micro and Nano MaterialsXuchang UniversityXuchang 461000China Laboratory of Fatigue and Fracture for Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

The variation of stacking fault energy(SFE)in a number of binary Cu alloys is predicted through considering the Suzuki segregation by the full potential linearly augmented plane wave(FPLAPW)*** calculated results show that some solute atoms(Mg,Al,Si,zn,Ga,Ge,Cd,Sn,and Pb),which prefer to form the Suzuki segregation,may decrease the value of SFE;while the others(Ti,Mn,Fe,Ni,zr,Ag,and Au),which do not cause the Suzuki segregation may not decrease the ***,it is interesting to find that the former alloying elements are located on the right of Cu group while the latter on the left of Cu group in the periodic table of *** intrinsic reasons for the new findings can be traced down to the valences electronic structure of solute and Cu atoms,i.e.,the similarity of valence electronic structure between solute and Cu atoms increases the value of SFE,while the difference decreases the value of SFE.

关键词： Cu-alloy Deformation behavior First-principles calculation Stacking fault energy

STUDY ON THE FINITE ELEMENT NUMERICAL SIMULATION OF SHEET METAL FORMING

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 299-302页

作者： j.L.Song D.j.Hu z.L.Chang T.Y.Li z.b.jiang School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China Department of Materials Engineering Taiyuan Heavy Machinery Institute Taiyuan 030024 China

based on the Finite Element Theory of Rigid Plastic,relevant problems during plas-tic simulation on sheet metal forming were technologically studied and simplified;a simplified model of the blank holder during the drawing process was established and the effects of related parameters on the forming processes were also *** the same time,a finite--element numerical simulation program SPID was *** distribution of strain and relationship of stress--stroke simulated were compared with experimented,the results are well coincided with each *** is verified that the analytical program is reliable.

关键词： sheet metal forming finite-element numerical simulation