检索结果-南通市图书馆

Microstructure and properties of high emissivity coatings

在线全文

学校读者我要写书评

暂无评论

Journal of University of Science and Technology Beijing 2008年第5期15卷 627-632页

作者： Zhigang Dan daqiang cang Huimin Zhou Hao Bai Yanbin Zong Chinese Research Academy of Environmental Sciences Beijing 100012 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Shangdong Huimin Technology Development Company Jinan 250100 China

A new coating on lining in industrial furnace for energy saving has been developed. Properties and microstructure of the coatings were revealed by emissivity instrument,X-ray diffraction （XRD）,transmission electron microscope （TEM） and scanning electron microscope （SEM）,respectively. The result indicates that the emissivity of coatings is higher than 0.90 and the thickness of coatings is about 200 μm. ZrO2,Cr2O3 and SiC in the coating benefit practical applications of coatings at high temperature with durable high emissivity and the continuous structure between the coatings and the substrate makes the coatings high cohesion and excellent adhesion for both specimens with and without sintering at high temperature. Result from laboratory experiment shows that the heating speed of specimen with coating is higher than that of controlled specimen and the temperature increases 30°C during the heating. The average temperature drop of specimen with coatings has a 13.5% improvement in the cooling speed. The application of coatings on the checker brick in a blast furnace of 1750m^3 indicates that the coating causes the blast temperature to an average increase of 28°C,reduces the fluctuation of blast temperature before the blowing-in and leads to a fuel saving of 10% approximately.

关键词： high emissivity coatings industrial furnace energy saving

Mechanism of phase separation in BFS (blast furnace slag) glass phase

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第1期54卷 105-109页

作者： LI Yu LIU XiaoMing SUN HengHu cang daqiang Key Laboratory of Ecologic and Recycle Metallurgy Ministry of Education University of Science and Technology Beijing Beijing 100083 China School of Engineering and Computer Science University of the Pacific Stockton CA 95211 USA

XRD,TEM,ED,and NMR analyzed four types of blast furnace slags (BFS) with different structures in this paper. The composition requirement for phase separation in BFS glass phase was then put forward,that is the composition of slag locates in the coexisting phase region of melilite and any silicate mineral with Q0 units. The special structure of melilite units,a 5-membered ring with high degree of polymerization (DOP),plays a key role in the formation of phase separation. In BFS system,one with chemical composition of larger ratio of (CaO + MgO/(SiO2 + Al2O3) would be more promising to meet the requirement for phase separation.

关键词： blast furnace slag (BFS) phase separation glass phase requirement melilite structure

Improving the solidification structure of commercially pure aluminium with electropulse acting on liquid metal

在线全文

学校读者我要写书评

暂无评论

Journal of University of Science and Technology Beijing 2007年第4期14卷 317-320页

作者： Heng Cui Yanbing Zong daqiang cang Lingzhen Li Jun Zhang Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China

The effect of electropulse on the solidification structure of commercially pure aluminium was studied. The orthogonal array L9 was used to determine the effect of three process parameters of electropulse modification （EPM）, which were pulse current intensity, pulse frequency, and treating time. For each factor, three levels were chosen to cover the experimental region. According to the experimental results, the solidification structure of commercially pure aluminium was modified from large grains with columnar crystals to finer grains with equiaxed crystals, by allowing the electropulse to act on liquid aluminium. However, the solidification structures could be refined differently at different EPM parameters. Certain EPM parameters should be selected to get the optimum solidification structure. Among the three parameters, pulse frequency was the most important factor influencing the solidification structure, the secondary factor was current intensity, and treating time was the third one. The optimum parameters were the pulse frequency of 5 Hz, the current intensity of 68 A, and the treating time of l0 s.

关键词： pulse current electropulse modification commercially pure aluminium solidification structure grain refinement

Casting structure of pure aluminum by electric pulse modification at different superheated temperatures

在线全文

学校读者我要写书评

暂无评论

Journal of University of Science and Technology Beijing 2005年第6期12卷 527-530页

作者： Jingang Qi Jianzhong Wang Xingjiang Liu Bing Wang daqiang cang Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China Department of Material and Chemical Engineering Liaoning Institute of Technology Jinzhou 121001 China

Electric pulse modification （EPM） is a novel technique that reduces grain size by altering the structure of a melt. It was investigated that the response of the casting structure of high pure aluminum to EPM in different superheated melts. The results indicate that the grain refining effect of a given pulse electric field holds an optimal temperature range, moreover, a lower or higher superheated temperature will both disadvantage the improvements of casting structure. It essentially lies in the cooperative action between the distorted absorption of clusters and the activated capability of atoms in the aluminum melt.

关键词： electric pulse modification superheat casting structure cluster activated ability

A new hybrid method—combined heat flux method with Monte-Carlo method to analyze thermal radiation

在线全文

学校读者我要写书评

暂无评论

Journal of University of Science and Technology Beijing 2006年第1期13卷 25-28页

作者： Zengwu Zhao daqiang cang Wenfei Wu Yike Li Baowei Li Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China Inner Mongolia University of Science and Technology Baotou 014010 China

A new hybrid method, Monte-Carlo-Heat-Flux （MCHF） method, was presented to analyze the radiative heat transfer of participating medium in a three-dimensional rectangular enclosure using combined the Monte-Carlo method with the heat flux method. Its accuracy and reliability was proved by comparing the computational results with exact results from classical ＂Zone Method＂.

关键词： radiation heat transfer scattering numerical simulation Monte-Carlo method heat flux method

The cluster size transformation model of molten alloy under pulse electric field

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2008年第3期51卷 302-307页

作者： ZHANG ZhenBin WANG JianZhong QI JinGang WANG Bing HE LiJia cang daqiang School of Metallurgical and Ecological Engineering University of Science and Technology of BeijingBeijing 100083China College of Materials Science and Chemical Engineering Liaoning Institute of TechnologyJinzhou 121001China

Based on the electric dipole theory, the coupled field distribution of pulse electric field (PEF) with electric dipole field around the cluster in superheated molten alloy is simulated under the effect of PEF. For the difference of electro-migration, the atom of solute and solution will accumulate around the cluster, and then the smaller cluster may reorganize and grow up under the action of the coupled field. We also apply the electrostatic induction theory to analyze the bearing behavior of the half side of the cluster. The bigger the cluster is, the stronger the electrostatic force is, therefore, the bigger cluster's stability is weak apparently. The study indi- cates that the cluster in the superheated molten has the homogeneous tendency under the effect of PEF.

关键词： pulse electric field static electricity induction electric dipole cluster model

Effect of electric pulse treatment on solidification structure of an Al-15%Si alloy

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2005年第3期24卷 288-292页

作者： SHI Xiangdong WANG Jingsong XUE Qingguo cang daqiang WANG Liping WU Shupiao Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China Sinosteel Sci-Tech Development Company Beijing 100031 China Shijiazhuang Iron and Steel Co. Ltd. Shijiazhuang 050031 China

The effect of electric pulse modifying on the solidification structure of an Al-15%Si alloy was investigated. The result shows that the primary silicon disappears sometimes and the eutectic phase is refined after the treatrnent of EP （electric pulse） though there are different modalities in different treating durations. DSC （differential scanning calorimetry） analysis indicates that the super-cooling texture decreases and the freezing range narrows evidently after the electric pulse treatment.

关键词： solidification structure electric pulse Al-Si alloy DSC

Study on Improving Solidification Structure of Rare Earth Al-Si Alloys with Electropulse Acting on Liquid Alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2004年第Z1期22卷 49-52页

作者： Cui Heng cang daqiang Zong Yanbing Li Lingzhen He Peng Mo Zhiying School of Metallurgy and Ecology Engineering University of Science and Technology BeijingBeijing 100083 China School of Metallurgy and Ecology Engineering University of Science and Technology BeijingBeijing 100083 China School of Metallurgy and Ecology Engineering University of Science and Technology BeijingBeijing 100083 China School of Metallurgy and Ecology Engineering University of Science and Technology BeijingBeijing 100083 China School of Metallurgy and Ecology Engineering University of Science and Technology BeijingBeijing 100083 China School of Metallurgy and Ecology Engineering University of Science and Technology BeijingBeijing 100083 China

Electropulse modification (EPM) process, a new physical field method for improving the solidification structure of metals was *** from other research, EPM is only acting pulse current on melt under liquid *** solidification structure of Al-Si alloys, A1-Cu alloys,cast iron and steel can be modified obviously with this method: the solidification structure of ZL101 alloy presented the Na and Sr modification and the mechanical properties were enhanced; a large number of primary silicon appeared in the microstructure of ZL109 alloy; the equiaxed grain zone was expanded and the grains were fined in Al-5.0wt% Cu alloy; the graphitization took place in solidification process of molten cast iron; the grain sizes of solidification structure of T8 steel were reduced significantly and the shape of steel pearlites also changed; the equiaxed grain zone increased to 88% from original untreated 19%, the equiaxed grains were fined and the intercrystalline crack was avoided in concasting billet by continuously treating liquid electrical sheet steel in *** of rare earths on casting Al-Si alloys were also *** method of modifying the solidification structure of rare earth Al-Si alloys with EPM in producing the alloys was proposed.

关键词： electropulse modification Al-Si alloy solidification structure rare earths

Restraining NO_x Formation during Coal Combustion in Packed Bed

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 1998年第2期12卷 70-74页

作者： Shengli Wu Chunbao Xu Qiushuang Shou daqiang cang Metallurgy School, UST Beijing, Beijing 100083, China Metallurgy School UST Beijing Beijing 100083 China

The effects of various combustion conditions (i. e. particle size of coals, oxygen concentration in combustion gas and coal content in the fuel bed, etc.), on reducing conversion of NO_x during coal combustion were studied. Under the present combustion conditions, coals with smaller particle size gave the lower conversion of NO_x, and as expected that an decrease in overall stoichiometric ratio, whether by an decrease in O_2 content in combustion gas or by an increase in coal content in fuel bed would lead to a lower conversion of NO_x. In order to investigate the effect of metallic oxide layers on restraining NO_x formation, the combustion experiments for coal granules with adhering layer of various metallic oxides including Fe_2O_3, Ni_2O_3 and mixed oxides Fe-Ni-O_x were conducted in a packed bed combustor. The combustion experiments have shown that most of adhering materials gave considerable effect on reduction of NO_x emission during coal combustion.

关键词： coal combustion NO_x formation restraining metallic oxide