材料期刊网

Friction Stir Welding of Discontinuously Reinforced Aluminum Matrix Composites: A Review

D.Wang , B.L.Xiao , D.R.Ni , Z.Y.Ma

金属学报(英文版) doi:10.1007/s40195-014-0143-2

关键词:

Shape Memory Alloy-Reinforced Metal-Matrix Composites:A Review

D.R.Ni , Z.Y.Ma

金属学报(英文版) doi:10.1007/s40195-014-0164-x

关键词:

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 OF HYDROGEN ABSORBING ALLOYS IN JAPAN

K. Mii (Sumitomo Metal Industries , Ltd. , 1-t-3 Otemachi , Tokyo 100 , Japan)M Amano (National Research Institute for Metals , 1-2-1 Sengen , Tsukuba 305 , Japan)

金属学报(英文版)

The R & D of hydrogen absorbing alloys in Japan started in the early 1970s.Many alloys such as TiMm1.5 based alloys, Fe-Ti-O alloys (e.g. FeTi1.15 O0.024) andthe(mischmetal)Ni5 based alloys (e.g. MmNi4.5 Cr0.46 Mn0.04) were developed by the early 1980s. The application of these alloys to hydrogen storage, heat storage, heat pump, hydrogen purification and motor vehicles has been tried in many iaboratories,and the various techniques for using hydrogen absorbing alloys have been developed.The standarkization of evaluation methods for hydrogen absorbing alloys has been promoted by the Ministry of International Trade and Industry (MITI), and four of them were established as Japanese Industrial Standard (JIS).Alloys for Ni-Metal Hydride batteries have been extensively investigated since 1987in Japun. Mm-Ni-Co-Al-Mn alloys (e.g. MmNi3.55 Co0.75Al0.9Mn0.4) have been devel-oped and commereialized since 1990. The amount of production of small-size Ni-MH batteries in 1995 was about three hundred milliion in number and about one hundred billion yen. The R & D for higher enerpy-density Ni-MH batteries is intensively in progress.MITI and STA (Science and Technology Agency) have promoted the R & D of hydro-gen absorbing alloys in Japan by carrying out the national projects such as Sunshine Program (MITI: 1974-1993) and Utilization of Wind Engeray (STA 1980-1985). The New Sunshine Program (MITI 1993-2020) have started in 1993. This program con-tains the application of hydrogen absorbing alloys to Economical- Enerpy- City System and to We-NET (International Clean Energy System of Technology Utilizing Hydro-gen: World Energy Network.

关键词: hydrogen absorbing alloy , 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

Structural and magnetic properties of R(Fe,Ni)(11.3)Nb-0.7 compounds with R=Dy and Er

Journal of Physics-Condensed Matter

The effect of the substitution of Ni for Fe on the magnetic and structural properties of RFe11.3Nb0.7 compounds (R = Dy and Er) has been studied. All of the compounds studied crystallize in the ThMn12 type of structure and the lattice constants a and c decrease with increasing Ni content. Substitution of Ni for Fe leads to a clear increase of the Curie temperature and to a decrease of the saturation magnetization. The temperature dependencies of the ac susceptibility and the magnetization indicate spin reorientations in all of the compounds. The easy-magnetization direction at room temperature has been determined to be along the c-axis from x-ray diffraction patterns of magnetically aligned samples. The effect of Ni substitution on the magnetocrystalline anisotropy is also discussed.

关键词:

Key R&D activities for development of new types of wrought magnesium alloys in China

Transactions of Nonferrous Metals Society of China

Many researchers in China are actively engaged in the development of new types of wrought magnesium alloys with low cost or with high-performances and novel plastic processing technologies. The research activities are funded primarily through four government-supported programs: the Key Technologies R&D Program of China, the National Basic Research Program of China, the National High-tech R&D Program of China, and the National Natural Science Foundation of China. The key R&D activities for the development of new wrought magnesium alloys in China are reviewed, and typical properties of some new alloys are summarized. More attentions are paid to high-strength wrought magnesium alloys and high-plasticity wrought magnesium alloys. Some novel plastic processing technologies, emerging in recent years, which aim to control deformation texture and to improve plasticity and formability especially at room temperature, are also introduced.

关键词: wrought magnesium alloy;microstructure;properties;alloy designing;plastic deformation;research projects;y-zr alloys;mechanical-properties;mg-4y-4sm-0.5zr alloy;grain-refinement;rare-earth;microstructure;gd;phase;temperature;evolution

Exceptionally strong magnetism in the 4d perovskites RTcO(3) (R = Ca, Sr, Ba)

Physical Review B

The evolution of the magnetic ordering temperature of the 4d(3) perovskites RTcO(3) (R = Ca, Sr, Ba) and its relation with its electronic and structural properties has been studied by means of hybrid density functional theory and Monte Carlo simulations. When compared to the most widely studied 3d perovskites the large spatial extent of the 4d shells and their relatively strong hybridization with oxygen weaken the tendency to form Jahn-Teller like orbital ordering. This strengthens the superexchange interaction. The resulting insulating G-type antiferromagnetic ground state is characterized by large superexchange coupling constants (26-35 meV) and Neel temperatures (750-1200 K). These monotonically increase as a function of the R ionic radius due to the progressive enhancement of the volume and the associated decrease of the cooperative rotation of the TcO(6) octahedra.

关键词: total-energy calculations;augmented-wave method;basis-set;oxides

ANOMALOUS 3D-ANISOTROPY OF R2FE14C AND R2FE14B COMPOUNDS

Journal of Magnetism and Magnetic Materials

The temperature dependence of the anisotropy field H(A) and the thermal expansion DELTA-l/l0 of R2Fe14X (R = Gd, Lu; X = B,C) were measured by applying the SPD technique for H(A)(T) and a membrane technique for DELTA-l(T)/l0. Comparing Lu2Fe14B and Lu2Fe14C the difference in the temperature dependence of H(A) is associated with the difference in the Invar-like thermal expansion between the two compounds.

关键词: 3d magnetism;anisotropy;gd2fe14b

D301R树脂对水溶液中硝基苯的吸附性质

华英杰 , 王崇太 , 李天略 , 何猛雄 , 徐坤琴

应用化学 doi:10.3724/SP.J.1095.2011.00631

研究了D301R弱碱性阴离子交换树脂对水中硝基苯的吸附作用,测定了不同温度下吸附的动力学曲线和吸附等温线,提出了吸附动力学模型,计算了平衡吸附量、吸附活化能和吸附焓等.实验结果表明,吸附动力学符合表面过程控制的准二级反应模型,其速率常数k2在300 K时为3.74×10-2 g/(mg·min),并随温度的升高而升高；平衡吸附量在300 K时为5.02 mg/g,且随温度的升高而降低；吸附活化能为39.02 kJ/mol;吸附等温线符合Langrnuir吸附模型,吸附焓为-22.47 kJ/mol,吸附作用力主要是氢键.

关键词: D301R树脂 , 硝基苯 , 吸附动力学 , 吸附等温线