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EXPERIMENT AND SIMULATION FOR THICK-PLATE BENDING BY HIGH FREQUENCY INDUCTOR

S. Imatani , Y. Okuno and T. Inoue (Department of Energy Conversion Science , Kyoto University , Sakyo-ku , Kyoto 606-8501 , Japan)

金属学报(英文版)

In order to produce thick plates with complicated curved surface, a prototype bending machine by use of high frequency inductor is developed. The bending mechanism is based on the localized thermal stresses which are induced from the difference of temperature in thickness by the high frequency inductor. The operating speed and the thickness of plate are examined from the experiment, and the variation of temperature is measured. Finite element analysis is carried out, in the second part, based on the experimentally obtained temperature distribution. So-called "Mindlin plate element"is used in order to perform the simulation efficiently. We discuss the strategy to produce such curved surface in the practical process and describe further perspective of the production system.

关键词: plate bending , null , null , null , null

Cerium chemical conversion coating for aluminum alloy 2024-T3 and its corrosion resistance

Corrosion

New golden. yellow-colored cerium chemical conversion coatings on aluminum alloy 2024-T3 (AA2024-T3 [UN A92024]) surface at room temperature were obtained by immersing the alloy into a cerium solution containing zinc chloride (ZnCl2) and hydrogen peroxide (H2O2). Electrochemical methods and immersion tests were used to study the dynamics of the coatings formation and their corrosion resistance in 3.5% sodium chloride (NaCl) solution. The morphologies of the coatings were recorded by scanning electronic microscopy (SEM). Energy-dispersive x-ray (EDX) analysis and x-ray photoelectron spectroscopy (XPS) were used to analyze the chemical composition and the oxidation state of the elements in the coatings. Polarization experiments and immersion tests in 3.5% NaCl solution showed that the sensitivity to pitting corrosion for the conversion-coated AA2024-T3 was greatly lower than that of the untreated specimens, and the corrosion resistance improved markedly. SEM photographs showed that the coatings consisted of a lot of spherical particles. EDX and XPS experimental results showed that the coatings were made up of oxygen, cerium, and aluminum, and the spherical particles contained higher contents of cerium and oxygen than the other sites. Cerium was mainly in the form of Ce4+. The mechanisms of conversion coatings formation and improvement on corrosion resistance also are discussed.

关键词: aluminum;cerium;conversion coating;corrosion resistance;electrochemistry;scanning electronic microscopy;x-ray photoelectron;spectrum;x-ray-absorption;al-alloys;edge spectroscopy;pitting corrosion;protection;inhibition;surface;xps

Correctness and completeness of the theory of bio-energy transport Reply to the comments on "The theory of bio-energy transport in the protein molecules and its properties"

Physics of Life Reviews

Commentaries by Philip W.T. Pong, Nongyue He, S.D. Liang, Tao Song, Yuri Gaididei and Sergey Volkov and Alexander Y. Grosberg on my review article (Pang, 2011 [1]) are answered. The validity of Davydov's mechanism of bio-energy transport, the completeness of theory, outstanding problems, the normalization and validity of wave function of the system in Pang' model as well as other related problems are elucidated in detail. (C) 2011 Elsevier B.V. All rights reserved.

关键词: biological temperature;3 channels;soliton;model

Corrosion behavior of rare earth metal (REM) conversion coatings on aluminum alloy LY12

Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing

The processes of the double layer rare earth metal (REM) conversion coating on aluminum alloy LY12 (2024) were introduced. The results of polarization tests showed that the corrosion resistance of the double layer REM conversion coating was superior to that of chromate conversion coating. The corrosion behavior of REM conversion coatings on LY12 alloy was studied with optical microscopy and energy dispersive spectroscopy (EDS). The results showed that in NaCl solution, pits initiated on the coatings formed on Cu-rich intermetalics. According to the equivalent circuit of pitting, a new method for analyzing the pit growth of REM conversion coatings was put forward by employing electrochemical impedance spectroscopy (EIS). Transmission line W in equivalent circuit could be neglected in short term exposure of REM conversion coatings to NaCl solution. This led to a formula for calculating the area fraction of pitting (F) on the surface of REM conversion coatings by simplifying the equivalent circuit. (C) 2000 Elsevier Science S.A. All rights reserved.

关键词: LY12 alloy;REM conversion coatings;corrosion behavior;electrochemical;impedance spectroscopy (EIS);equivalent circuit;film-forming inhibitors;surface modification;stainless aluminum;protection

Gibbs Free Energy of Formation of 3Y_2O_3·5Al_2O_3

XU Xiuguang WANG Changzhen TU Ganfeng Northeast University of Technology , Shenyang , China.

材料科学技术(英文)

Thermodynamic properties of 3Y_2O_3·5Al_2O_3 double compound have been determined with CaF_2 single crystal electrolyte galvanic cell at 1049 K to 1230 K.The galvanic cell used can be expressed as: Pt,O_2(g)丨Y_2O_3(s),YOF_((s))丨CaF_2丨YOF_((s)), 3Y_2O_3·5Al_2O_(3(s))丨Al_2O_(3(s))丨O_2(g),Pt, of which the cell reaction is; 3Y_2O_(3(s))+SAl_2O_(3(s))=3Y_2O_3·SAl_2O_(3(s)) The following result is obtained: A_fG°(3Y_2O_3·5Al_2O_3)=-939500+765.90T±710J/mol where,△fG°(3Y_2O_3·5Al_2O_3)is the free energy of formation of 3Y_2O_3·5Al_2O_3 from Y_2O_3 and Al_2O_3.

关键词: rare earth , null , null

Energy spectrum and its pressure-induced shift and J-T effect of ZnTe : Mn2+

Communications in Theoretical Physics

By using strong-field scheme, the complete d(5) energy matrix with D-2d symmetry has been constructed. Then, by diagonalization of this matrix at normal and various pressures, the whole energy spectrum [including the ground-state zero-field splitting (GSZFS)] and its pressure-induced shift (PS) of ZnTe:Mn2+ have uniformly been calculated. The results are in very good agreement with experimental data. According to the eigenfunctions and PS, the assignments of four absorption bands have been given. By taking into account the effect of different deformations of t(2) and e radial wavefunctions on t(2)(3)((4)A(2))e(2)((3)A(2))(4)A(1) and t(2)(3)(E-2)e(2)((3)A(2))E-4, the position of the third absorption band at normal pressure has been estimated. The tetragonal field is important for GSZFS of ZnTe:Mn2+ and its PS, which supports the existence of tetragonal Jahn-Teller distortion in ZnTe:Mn2+. The physical essentials of typical levels, GSZFS and their PS have been revealed.

关键词: crystal fields;high pressure;optical properties;energy spectrum;Jahn-Teller effect;covalency effect;ZnTe : Mn2+;ligand-field calculation;theoretical calculations;zn1-xmnxte;ruby;epr

基于(火积)耗散率最小的T-Y形肋片构形优化

冯辉君 , 陈林根 , 谢志辉 , 孙丰瑞

工程热物理学报

基于构形理论,以导热和对流换热总(火积)耗散率最小为优化目标,对T-Y形肋片进行构形优化,得到同时考虑导热和对流换热(火积)耗散性能的T-Y形肋片最优构形.结果表明:存在最佳单元级直肋和中部空腔高度和长度比使得T-Y形肋片无量纲当量热阻取得二次最小值.增大肋片高度和长度比和肋片占比有助于提高T-Y形肋片整体传热性能.T-Y形肋片与T形肋片相比,T-Y形肋片二次最小无量纲当量热阻降低32.33%,此时T-Y形肋片温度梯度场更均匀,整体传热性能得到明显提高.

关键词: 构形理论 , (火积)耗散率最小 , T-Y形肋片 , 对流换热 , 广义热力学优化

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