材料期刊网

The States-of-arts and Key Scientific Issues on Durability Research of Concrete Structures

武汉理工大学学报-材料科学版(英文版)

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Review On Research And Development Of Magnesium Alloys

Z. Yang , J.P. Li , J.X. Zhang , G.W.Lorimer , J. Robson , null , null , null , null

金属学报(英文版)

The current research and development of magnesium alloys is summarized. Several aspects of magnesium alloys are described: cast Mg alloy, wrought Mg alloy, and novel processing. The subjects are discussed individually and recommendations for further study are listed in the final section.

关键词: Magnesium alloys , null , null

Growth mechanism of carbon microcoils with changing fiber cross-section shape

新型炭材料

Carbon microcoils (CMCs) with a fiber cross-section changing from flat to circular along with a coil diameter changing from 4.2 to 6.0 mu m, which may develop a novel spring for micromechanical systems, were obtained by controlling the acetylene flow rate using Ni catalyst at a temperature of 1 013-1 053 K. A growth model for these changes was proposed in which catalytic anisotropy is considered to be the possible factor changing the fiber cross-section shape of the CMCs. Owing to the change of catalytic anisotropy caused by reaction conditions, the same slender catalyst can produce both flat CMCs and circular CMCs depending on its relative orientation to the fiber axis. A cubic Ni catalyst can only produce a circular CMC, and can only change the coil diameter upon changing the reaction conditions. The model will give more insight into the formation of CMCs and provide information on the controlled synthesis of CMCs and carbon fibers.

关键词: Carbon microcoils;Growth model;Ni Catalyst;Catalytic anisotropy;chemical-vapor-deposition;extension characteristics;catalytic;pyrolysis;acetylene;coils;morphology;substrate

Jian ZHANG/Langhong Lou

材料科学技术（英）

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RESEARCH AND DEVELOPMENT OF HIGH TEMPERATURE STRUCTURAL MATERIALS FOR AERO-ENGINE APPLICATIONS

G.Q. Zhang

金属学报(英文版)

The status of research, development of superalloys and materials processing & fabrication technologies for aero-engine applications in China Aviation Industry, with an emphasis on recent achievements at BIAM including directionally solidified and single crystal superalloys for blade and vane applications, wrought superalloys for aero-engine disks and rings, and powder metallurgy (PM) superalloys for high performance disk applications were described. It was also reviewed the development of new class of high temperature structural materials, such as structural intermetallics, and advanced material processing technologies including rapid solidification, spray forming and so on. The trends of research and development of the above mentioned superalloys and processing technologies are outlined. Cast, wrought and PM superalloys are the workhorse materials for the hot section of current aero-engines. New high temperature materials and advanced processing technologies have been and will be the subject of study. It is speculated that high performance, high purity and low cost superalloys and technologies will play key roles in aero-engines.

关键词: superalloy , null , null

Study on Thermal Simulation of Solidification in Heavy Section Ductile Iron

Zhenhua LI , Yanxiang LI , Huiyuan GENG , Jianjun CHEN , Chunyan ZHOU , Junfa CHEN

材料科学技术（英）

Using an artificial intelligent instrument and a computer feedback control method, a new thermal simulation system is studied. Based on numerical simulation of casting solidification, a sample in the new system successfully simulated the solidification of heavy section ductile iron. The results show that the new thermal simulation system is accurate and reliable. Not only cooling curve but also graphite in the center of the thermal sample and the heavy section ductile iron is identical. Realization of accurate thermal simulation of solidification in heavy section ductile iron will be helpful for studying formation mechanism and controlling graphite degeneration in heavy section ductile iron.

关键词: Thermal simulation , null , null

410℃ ISOTHERMAL SECTION OF Al-Cu-Sb PHASE DIAGRAM

CHEN Rongzhen ZHANG Hanxing ZHENG Jianxuan Guangxi University , Nanning , ChinaHE Hanping Guangxi Research Institute of Nonferrous Metals and Geology , Nanning , China CHEN Rongzhen , Professor , Department of Physics of Guangxi University , Nanning , Guangxi 530004 , China

金属学报(英文版)

The 410℃ isothermal section of the phase diagram of Al-Cu-Sb ternary system has been de- termined by means of X-ray powder diffraction method and electron probe microanalysis. The section determined consists of 12 single-phase regions,21 bi-phase regions and 10 tri-phase regions.

关键词: Al-Cu-Sb ternary system , null , null

700℃ ISOTHERMAL SECTION OF THE Pd-Ru-Gd PARTIAL PHASE DIAGRAM

K.H Zhang and L.L. Chen (Institute of Precious Metals , Kunming 650221 , China)

金属学报(英文版)

The 700℃ isothermal section of the Pd-Ru-Gd partial ternary phase diagram containing more palladium than ruthenium was determined by X-rag diffraction analysis and optical microscopy. The section consists of seven single-phase regions,eleven two-phase regions and five three-phase regions. A new ternary compound Pd2RuGd2,which exhibits a tetragonal structure with a=0.7492 nm and c=0.7445 nm, has been found.

关键词: : palladium , null , null , null , null

ROOM TEMPERATURE AND 750℃ ISOTHERMAL SECTION OF Ag-Pd-Gd(Gd≤25 AT.-%)PHASE DIAGRAM

ZHANG Kanghou CHEN Lili Kunming Institute of Precious Metals , Kunming , China ZHANG Kanghou , Kunming Institute of Precious Metals , Kunming 650221 , China

金属学报(英文版)

The room temperature section and the 750℃ isothermal section of the Ag-Pd-Gd ternary phase diagram containing 0—25 at.-% Gd are constructed by X—ray diffraction analysis and optical microscopy.Each section consists of 3 single phase regions,3 bi-phase regions and I tri-phase region respectively.

关键词: Ag-Pd-Gd ternary system , null

ISOTHERMAL SECTION AT 1000 AND 1100℃ OF Fe-Mn-Al PHASE DIAGRAM

LIU Xingjun HAO Shiming SUN Rongyao Northeast University of Technology , Shenyang , China Department of Materials Science and Engineering , Northeast University of Technology , Shenyang 110006 , China

金属学报(英文版)

Phase equilibria at Fe-Mn side of isothermal section at 1000 and 1100℃ in Fe-Mn- Al system have been determined using the diffusion couple technique and metallography. A three-phase,α+γ+β,region was found at 1000℃.The method of solid/gas diffusion couple used to determine equilibrium phase composition is believed to be feasible for the system containing volatile component.

关键词: Fe-Mn-Al system , null , null