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
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null
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null
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
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
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null
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null
Zhenhua LI
,
Yanxiang LI
,
Huiyuan GENG
,
Jianjun CHEN
,
Chunyan ZHOU
,
Junfa CHEN
材料科学技术(英文)
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
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null
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null
CHEN Rongzhen ZHANG Hanxing ZHENG Jianxuan Guangxi University
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Nanning
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ChinaHE Hanping Guangxi Research Institute of Nonferrous Metals and Geology
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Nanning
,
China CHEN Rongzhen
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Professor
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Department of Physics of Guangxi University
,
Nanning
,
Guangxi 530004
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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
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null
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