检索结果-南通市图书馆

FORMABILITY AND CRYSTAL TYPES OF RARE EARTH-SILICON CONTAINING TERNARY COMPOUNDS

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 1993年第3期3卷 17-19页

作者： Tang, Bo Chen, Nianyi shanghai Institute of Metallurgy, Academia Sinica, shanghai 200050, China

By pattern recognition chemical bond parameter method, the formability of NaZn13 type and BaCd11 type ternary compounds in RE-M Si （RE=La-Lu, M is any metallic element） systems has been investigated. And the existen... 详细信息

关键词： RE-M-Si system ternary compounds crystal type

Synthesis and crystal structure of SrNi_xV_(6-x)O_(11)

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1997年第10期42卷 850-855页

作者： LIU Hongchao, GUO Changlin and TU Hengyongshanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, China shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai China

THE AV6O11（A,alkaline or alkaline earth metals）-type compounds are the only phases

关键词： SrNixV6-xO11 crystal structure X-ray powder diffraction Rietveld method bond-valence method.

Microstructure and Mechanical Properties of Dy-α-sialon/Nano-size SiC Composites

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1997年第4期13卷 336-338页

作者： Danyu JIANG Chen ZHANG Jianlin SHI Tingrong LAI and Dongsheng YAN(shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, China) shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

The composite of Dy-α-sialon/10 wt pct nano-size SiC particles has been prepared from precursor powders of Si3N4, AIN, Al2O3, Dy2O3 and nano-size β-SiC. The hardness, toughness and bending strength of the composite at ambient temperature are a little higher than those of Dy-α-*** the bending strength is maintained up to 1000℃ and about 2 times more than that of Dy-α-sialon at the same temperature. The fracture surfaces show that the grain size of the composite is smaller than that of Dy-α-sialon, and both Of them have predominately transgranular mode of fracture. It is believed that the decrease of the bending strength of Dy-α-sialon at elevated temperature is caused by the viscous flow of the grain boundary phase, while the addition of nanosize SiC particles effectively increases the viscosity of the grain boundary phase and therefore prevents the strength loss of Dy-α-sialon/nano-size SiC composites at elevated temperature

关键词： Microstructure and Mechanical Properties of Dy sialon/Nano-size SiC Composites SiC Nano

Removal Behaviors of Different SiC Ceramics during Polishing

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2010年第2期26卷 125-130页

作者： Guiling Liu, Zhengren Huang , Xuejian Liu and Dongliang Jiang Structural Ceramics Center, shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, China Structural Ceramics Center Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Comparative experiments were conducted to reveal the removal behaviors of three kinds of silicon carbide （SIC） ceramics during polishing and the effects of ceramic microstructure on the surface quality were also reported. Experimental results show that the second phase in SiC ceramics plays an important role in the surface quality when its size is large enough. The surface quality is enslaved to the formation of steps at interfaces between second phase and SiC matrix that results from different elastic modulus and hardness between two phases. Under 3 μm abrasive grains polishing condition, different SiC ceramics show different removal mechanisms. With decreasing abrasive grain size, all of different SiC ceramics exhibit a ductile removal mode, which decreases surface roughness efficiently.

关键词： SiC Surface quality Removal behavior Polishing

Effects of A1 Additions on Microstructure and Mechanical Properties of MoSi_2

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1999年第6期15卷 578-580页

作者： Jianlin LI Dongliang JIANG and Shouhong TAN(shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, shanghai 200050, China) shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 1295 Dingxi Road China

The effects of Al additions on the microstructure and mechanical properties of MoSi2 have been studied. With the A1 additions from 2.5 wt pct to 5 wt pct, the siliceous grain boundary phase in hot pressed samples was eliminated because of the formation of Al2O3 particles. It was shown that Al and SiO2 reacted at 860℃. During the reaction, A1 atoms were mainly transferred to Al2O3 particles, and to some extent, diffused into MoSi2 grains. Both the toughness and strength of Al containing composites exceeded those of pure MoSi2 material. Bending strength and fracture toughness reach the highest value of 350 MPa, 4.05 MPa.m1/2, respectively, at ambient temperature when Al addition was of 3.5 wt pct.

关键词： Figure MPa Effects of A1 Additions on Microstructure and Mechanical Properties of MoSi2

<100> Textured Diamond Film on Silicon Grown by Hot Filament Chemical Vapor Deposition

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1995年第6期11卷 426-428页

作者： Xuanxiong ZHANG Tiansheng SHI and Xikang ZHANG (State Key Laboratory of Functional Materials for Informatics, shanghai Institute of Metallurgy,Chinese Academy of Sciences, shanghai, 200050, China) shanghai Inst of Metallurgy Chinese Acad of Sciences Shanghai China

The textured growth of diamond film on HF eroded silicon wafer has been studied by HFCVD. The evolution of grain size and sudece morphology vs deposition time is presented and the textured thick diamond film (80μm)... 详细信息

关键词： Textured Diamond Film on Silicon Grown by Hot Filament Chemical Vapor Deposition OO

On the Formability of Some Metastable Alloy Phases

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1994年第1期10卷 23-26页

作者： Bo TANG Deshan KANG Pei QING Weiming ZHANG and Nianyi CHEN(shanghai Institute of Metallurgy, Chinese Academy of Sciences, shanghai, 200050, China) shanghai Inst of Metallurgy Shanghai China

Pattern recognition and neural network methods have been used to investigate the formability of metastable alloy phases, It has been found that some chemi cal bond parameters Such as valence electron number, electronegativity and metallic radii of cor-nponent elements are the dominating fac tors affecting metastable alloy phase formation. Some semi-empirical rules found in this way may be useful for the construction of expert system for materials design.

关键词： Figure Cd Ni On the Formability of Some Metastable Alloy Phases Chen Pb Sn Ta

Morphologies of solid-liquid interface and surface steps during rapid growth of BaB_2O_4 single crystals

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2007年第4期50卷 539-545页

作者： PAN XiuHong, AI Fei, JIN WeiQing, LIU Yan & ZHANG Ying shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, China shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai China

The evolution of solid-liquid interface during BBO single crystal growth was stud- ied by the differential interference microscopy. And the step morphology on (0001) surface of the as-grown crystal was observed by the atomic force microscopy as well. It was found that the transition from a flat solid-liquid interface to a skeletal shape will occur in case of rapid growth. However, AFM images of surface steps revealed morphology differences correlated with crystallographic directions. The steps advancing along direction form the step flow, whereas those steps propagating along direction shape into step segments. Measurements of step heights by AFM indicated that it is the high anisotropy of the dimension of growth unit and step bunching due to the enlargement of concentration difference along the surface that results in the anisotropy of step morphologies.

关键词： crystal growth morphological instability growth step AFM observation

Instability and Non-reproducibility of Gibbsite Precipitation Process in Alumina Powder Production

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1994年第3期10卷 209-212页

作者： Mei HONG Miaoxiu LIU Weiming ZHANG Bo TANG and Nianyi CHEN(shanghai Institute of Metallurgy, Academia Sinica, shanghai, 200050, China) shanghai Inst of Metallurgy Academia Sinica Shanghai China

Gibbsite (Al2O3 3H2O) powder. used for alumina powder production. can be prepared by the decomposition of sodium alum inate solutions induced by dilution or partial neutral ization, This decomposition process exhibits an incubation period and instability or non-reproducibility in reaction kinetics, UV time-scanning spectra and Raman spectra change have been measured to investigate the solution in incubation period and the factors affecting the grain size of gibbsite precipitate

关键词： Powders