材料期刊网

Optimization of electrical discharge machining characteristics of SiCp/LM25 Al composites using goal programming

R.Karthikeyan , S.Raju , R.S.Naagarazan , B.C.Pai

材料科学技术（英文）

In the present study an effort has been made to optimize the machining conditions for electric discharge machining of LM25 Al (7 Si, 0.33 Mg, 0.3 Mn, 0.5 Fe, 0.1 Cu, 0.1 Ni,.2 Ti) reinforced with green bonded SiC particles with approximate size of 25 mum. Polynomial models were developed for the various EDM characteristics such as metal removal rate, tool wear rate and surface roughness in terms of the process parameters such as volume fraction of SK, current and pulse time. The models were used to optimize the EDM characteristics using nonlinear goal programming.

关键词:

Optimization of Machining Characteristics for Al/SiCp Composites using ANN/GA

R.Karthikeyan , R.Adalarasan , B.C.Pai

材料科学技术（英文）

The present work is focused on optimization of machining characteristics of Al/SiCp composites. The machining characteristics such as specific energy, tool wear and surface roughness were studied. The parameters such as volume fraction of SiC, cutting speed and feed rate were considered. Artificial neural networks (ANN) were used to train and simulate the experimental data. Genetic algorithms (GA) was interfaced with ANN to optimize the machining conditions for the desired machining characteristics. Validation of optimized results was also performed by confirmation experiments.

关键词: Al/SiCp composites , null , null

R-line thermal shift and thermal broadenings of R, R' and B lines for ruby

Communications in Theoretical Physics

The unified theoretical calculation of thermal shifts (TS) of R-1 and R-2 lines and thermal broadenings (TB) of R, R' and B lines for ruby was carried out for the first time. The calculated results are in very good agreement with a great number of experimental data. Especially by using quantum theory and taking into account all the admixtures of wavefunctions within d(3) electronic configuration, all the Gamma M in electron-phonon interaction (EPI), the electronic energy spectrum and lattice-vibration Spectrum, the very important contributions to TS and TB from single-phonon direct process were theoretically calculated in detail. The microscopic essentials of various contributions are revealed, and the mistakes in previous work are remedied.

关键词: diamond anvil cell;pressure measurement;spectroscopy;temperatures

Theoretical calculations of thermal broadenings and transition probabilities of R, R ' and B line-groups for ruby

Communications in Theoretical Physics

On the basis of the unified calculation of the thermal shifts of R-1 line, R-2 line and ground-state-splitting as well as the thermal broadenings of R, R' and B line-groups for ruby, by taking into account all the levels and admixtures of wavefunctions within d(3) electronic configuration and all the GammaM in electron-phonon interaction, the transition probabilities of direct and Raman processes have theoretically been calculated. The thermal broadenings, of R, R' and B line-groups have successfully been interpreted in terms of the direct and Raman processes of acoustic phonons. The theoretically predicted transition probabilities are in good agreement with the experimental ones.

关键词: crystal fields;electron-phonon interaction;thermal broadening;transition probability;direct and Raman processes;shifts

Phase diagram of R-Fe-Co pseudoternary system with R <= 33.3% (mole fraction, R = Sm0.5Dy0.5)

Transactions of Nonferrous Metals Society of China

Phase equilibria of the R-Fe-Co pseudoternary system with R less than or equal to 33.3% ( mole fraction, R = Sm0.5Dy0.5) were determined in an isothermal section at 1073 K and a vertical section of RFe2-RCo2 by using OM, X-ray diffractometer, EP-MA DTA techniques. There are seven intermetallic phases: (Sm, Dy) (Fe, Co)(2), (Sm, Dy) (Fe, Co)(3), (Sm, Dy)(6) (Fe, Co)(23), (Sm, Dy)(2) (Fe, Co)(7), (Sm, Dy) (Fe, Co)(5), Th2Ni17-type and Th2Zn17-type (Sm, Dy)(2)(Fe, Co)(17). The (Sm, Dy)(6)(Fe, Co)(23) phase dissolves 36% Co(mole fraction) at 1073 K. However, the (Sm, Dy)(2)(Fe, Co)(7) phase in R-2(Fe1-xCox)(7) alloys dissolves about 19% Fe(mole fraction) at 1073 K.

关键词: rare earth-iron-cobalt;phase diagram;structure;compounds;sm-co;magnetic-properties;binary-system;magnetostriction

NEUTRON DIFFRACTION STUDY ON R_2Fel_(17)N_x(R=Y,Dy,Nd)

YANG Jilian ZHANC Baisheng DINC Yongfan China Institute of Atomic Engergy , Beijing , ChinaYANG Yingchang ZHANG Xiaodong Peking University , Beijing , ChinaPAN Shuming General Research Institute for Non-Ferrous Metals , Beijing , China associate professor , P.O.Box 275 , Branch No.30 , Beijing 102413 , China

金属学报(英文版)

The N occupying sites and magnetic structures in R_2Fe_(17)N_x(R=Y,Dy,Nd)are de- termined by neutron diffraction.The effects of the site occupation of N on magnetic properties are discussed primarily.

关键词: neutron diffraction , null , null , null , null , null

SPIN REORIENTATION AND EXCHANGE INTERACTIONS IN (ND, R)2FE14B (R = Y, GD)

Journal of Magnetism and Magnetic Materials

Exchange fields in both (Nd, Y)2Fe14B and (Nd, Gd)2Fe14B series are determined by analyzing spin reorientation. Results calculated for the two systems suggest that the R-R exchange interactions between R ions are comparable with the crystal-field interaction and that their effect might be taken into account for reproducing the spin-reorientation temperature.

关键词: magnetization process;crystal;nd2fe14b;r2fe14b;transition

R&D STATUS ON INTERMETALLICS IN CHINA

CHEN Guoliang(State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 , China)SHI Changxu (Academia Sinica , Beijing 100864 , China)

金属学报(英文版)

This paper briefiy introduces the R&D of intermetallics in China. R&D on intermetallics in a national scale in China began near ten years ago. The investigation in past years focused on the fundamental research and materials development. A significant progress has been made. Various components that made of Ti3Al Ni3Al, TiAl and Fe3Al have been successfully manufactured Some of them have been evaluted. It is expected that some intermetallic alloys will be produced in an industrial scale in the near future.

关键词: :intermetallic alloys , null , null , null

R & D ACTIVITIES ON AEROSPACE MATERIALS IN KOREA

H.M. Kim(Korea Institute of Machinery and Materials , Korea Manuscript received 26 August 1996)

金属学报(英文版)

This paper briefly reviews research and development programs in Korean aerospace industry,with an emphasis on aircraft materials technology. International collaborations in these areas are outlined and the R & D activities are highlighted against the　background of the national economy.It is shown that the investment from government agencies and large enterprises has led to healthy development of aerospace materials industries in Korea.

关键词: :R & D , null , null , null

Isofrax(R)和Insulfax(R)生物可溶性纤维的研究

朱炯 , 汤小明

材料工程 doi:10.3969/j.issn.1001-4381.2010.z2.095

综述生物可溶性纤维的研究进展,介绍矿物纤维对人体健康的影响以及国际上对矿物纤维进行健康分类的主要规范.分析了Unifrax公司研制Insulfrax(R)和Isofrax(R)两种可溶性耐火纤维的基本性能和应用情况.Isofrax(R)和Insulfrax(R)均是绿色环保型隔热材料,在欧美已成功地应用于各种热处理工业中.

关键词: 可溶性 , 纤维 , Insulfrax(R) , Isofrax(R)