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Annealing Texture Evolution of Ti-IF Steel during Batch Annealing

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 175-179页

作者： Jing shi Xianjin Wang(Material science and Engineering school, university of science and technology beijing, beijing 100083, china) Material science and Engineering school University of Science and Technology Beijing Beijing 100083 China

Texture development and recrystallization behavior of Ti-IF steel during Batch Annealing (BA) were investigared with X-ray diffraction and EBSP in lab, and the results were compared with research work on continu ous annealing (CA) with rapid heating rate. The basic tendencies are similar that eary nucleation takes place in ND fibers, RD fibers are consumed at the end of recrystallization, and ND texture dominates over annealing texture. However, the detailed texture transformation during batch annealing is different and somewhat more compicated than tha in rapid-heating process. Moreover, misorientation plays an important role in texture transformation of BA In addition, the results of EBSP are consistent with that of ODF well.

关键词： Ti-IF steel texture batch annealing X-ray diffraction EBSP

Effects of Surface-Active Elements Sulfur on Flow Patterns of Welding Pool

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Journal of Materials science & technology 2005年第3期21卷 408-414页

作者： Yuzhen ZHAO, Yongping LEI and Yaowu shi school of Materials science and Engineering, beijing {4. of technology, beijing 100022, china school of Materials science and Engineering Beijing University of Technology Beijing 100022 China

A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc (GTA) welding pool with different sulfur concentrations. It has been shown that, the weld penetration increases sharply with increasing sulfur content. When sulfur content increases beyond 80 × 10-6, the increase in sulfur content does not have an appreciable difference on the welding pool size and shape, and the depth/width remains constant. Sulfur changes the temperature dependence of surface tension coefficient from a negative value to a positive value and causes significant changes on flow patterns. The increase in soluble sulfur content and the decrease at free surface temperature can extend the region of positive surface tension coefficient. As sulfur content exceeds 125×10-6, the sign of surface tension coefficient is positive. Depending upon the sulfur concentrations, three, one or two vortexes that have different positions, strength and directions may be found in the welding pool. The contrary vortexes can efficiently transfer the thermal energy from the arc, creating a deep welding pool. An optimum range of sulfur content is 20-150×10-6.

关键词： Surface-active elements Sulfur Plow patterns Depth/width

Mechanism of Cathode Process of B(Ⅲ) in LiF-NaF-KBF_4.Meltby Electrochemical Titration Technique

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 203-207页

作者： Qingrong shi Xindong Wang Lianyu Yuan Shuzhen Duan(Applied science school, university of science and technology beijing, beijing 100083, china) Applied science school University of Science and Technology Beijing Beijing 100083 China

The mechanism of cathode process of B(Ⅲ) at molybdenum and platinum electrodes in LiF-NaF-KBF4.elt was studied and the transferred electron number of the reaction was calculated by means of cyclic *** effect of adsorption of electroactive component on the electrochemical response (e. g., the voltammetric i─Ecurves) was analyzed and discussed. The 'electrochemical spectra' for linear sweep voltammetry was used to elucidate the electrode reaction accompanied by a following transform process. The results show that the reduction ofB(Ⅲ) to B(0) proceeds in reversible one step three-electron reaction and the cathode process of B(Ⅲ) is affected byproduct adsorbed strongly at the electrode surface. It is assumed that the reduction and deposition of B(Ⅲ) at molybdenum and platinum electrodes proceed in two kinds of mechanism： (1) B(Ⅲ)＋ 3e = Bads→ B (surface diffusiondeposition mechanism) and (2) B(Ⅲ) ＋ 3e = B (direct deposition mechanism).

关键词： boron ions cathode process cyclic voltammetry fluoride melt

Experiment Study on Castex Process of AS Wire

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Journal of university of science and technology beijing 2001年第1期8卷 22-24页

作者： Zhiyuan shi Wanjun Wang Jinglin Wen Xinhua Wang Metallurgy school, university of science and {4. beijing, beijing 100083, china school of Materials and Metallurgy,Northeastern university, Shenyang 110006, china Metallurgy school Univ. of Science/Technology Beijing Beijing 100083 China

In order to optimize the Castex process of AS wire, the systematic experiments have been done for different process parameters with self-made DZJ-II 350 Castex machine. The parameters, such as casting temperature of aluminum, flow of cooling water, extrusion ratio and the gap between the surface of wheel and that of the mould, have been mainly studied. The results show that with the increase of casting temperature or rotating speed of wheel the measured length of liquid metal zone increases too. However, the length of liquid metal zone decreases with the increase of the flow of cooling water. Moreover, the relationship between the extrusion ratio and the extrusion power is studied.

关键词： Castex AS wire parameter length of liquid metal zone

β-Sialon Produced by Carbon Thermal Nitriding Reaction of Bauxite

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 209-213页

作者： Jun Wang, Nan Li, Caicheng shi, Chengchang Jia ( Material science and Engineering school, university of science and technology beijing, beijing 100083, china Material science and Engineering school, Wuhan university of science and technology, Wuhan 4.0 Material science and Engineering school University of Science and Technology Beijing Beijing 100083 China Material science and Engineering school Wuhan University of Science and Technology Wuhan 430081 China

β-Sialon was produced by carbon thermal nitriding reaction in N_2 gas atmosphere when the mixtures of bauxite and anthracite were put into vertical furnace. According to the mass loss of raw materials and the result of X-ray diffration (XRD) of products, the influences of the process parameters on the compositions and relative contents of products, such as the fixed carbon content, the flow of N2, the soaking time and the temperature, were researched.

关键词： β-Sialon bauxite anthracite carbon thermal nitriding processing parameter vertical furnace

Characteristics of Ore-Forming Fluids of Gold Deposits in Daqingshan District,Inner Mongolia,china

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 77-82页

作者： Jiuhua Xu YulingXie Dayi Qian Rufu Dine Jianping Li (Resource Engineering school, university of science and technology Beijha {4. 100083, china) (china university of Geosciences, {4. 100083, china) Resource Engineering school University of Science and Technology Beijing Beijing 100083 China china university of Geosciences Beijing 100083 China

***-weststrikingductileshearzonewithinagreelt,***:(1)pyrite-quartz,(2)quartz-Pyrite,(3)polymetallicsulfidesand(4.***-bearingveinsarenativegold,electrum,pyrite,chalcopyriteandgalena,buttheganguemineralsaremainlyquartz,secondarilysericite,***,silicification,***-formingfluidswerelowinsalinitieandhighinCO2content,MeasuredδDoffluidinclusionsinquartzfromtheoreveinsrangesfrom-65‰to-104.,butδ18Oquartzfrom10.0‰to12.8‰.Thesedatashowthatthewaterinhydrothermalfluidprecipitatingtheorebodiescouldhavebeenmainlymagmaticwaterandmetamorphicwaterbutlocalmeteoricwatermighttakepartinthelatemineralization.δ13Cfromfl

关键词： fluid inclusions isotope composition gold deposit Daqingshan area

Adhesion of NiCu Films DC Biased Plasma-Sputter-Deposited on MgO (001)

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 218-221页

作者： Hong Qiu, Mituru Hashimoto ( beijing Keda-Tianyu Microelectronic Material technology Development Corporation, beijing 100083,{4. Applied science school, university of science and technology beijing, beijing 100083,{4. Department of Applied Phys beijing Keda-Tianyu Microelectronic Material technology Development Corporation Beijing 100083 China Applied science school University of Science and Technology Beijing Beijing 100083 China Department of Applied Physics and Chemistry University of Electro-Communications 1-5-1 Chofugaoka Chofu-shi Tokyo 182-8585 Japan

NiCu films about 60nm thick were deposited on MgO (001) substrates at 230℃ by DC plasma-sputtering at 2.7kV and 8mA in pure Ar gas using a Ni90Cu10 target. A DC bias voltage of 0, 60, 110 or 14.V was applied to the substrate during deposition. The adhesion of the film to the substrate was studied using a scratch test as a function of . The application of is very effective in increasing the adhesion of the film to the substrate. In conclusion, the adhesion increases with cleaning the substrate surface by sputtering off impurity admolecules during the film initial formation due to the energetic Ar ion particle bombardment.

关键词： NiCu film plasma-sputter-deposition negative bias voltage adhesion

Direct Current Electric Arc-Electroslag Ladle Furnace

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Journal of university of science and technology beijing 2001年第2期8卷 98-100页

作者： Ping Wang, Jie Fu, Minsheng Sun, Xiangmao Kong, Zhimin Ma, Meilun shi, Xingjiang Wang (Metallurgy school, university of science and {4. beijing, beijing 100083, china) (Machinery Engineering school, university of science and {4. beijing, Be Metallurgy school University of Science and Technology Beijing 100083 China

In order to solve the high consumption problem of small capacity ladle furnace (LF), the operation principle and control method of the DC are and electroslag heating ladle furnace are introduced. With only one arcing electrode, the distance between the are and the wall of ladle is enlarged, and consequently the consumption of the ladle refractory is decreased. In the invention, a signal electrode is embedded in the refractory lining of the ladle, which contacts directly with the liquid steel and the ladle shell. Two graphite anode ends are submerged in the slag layer. The signal electrode is used as voltage reference during refining process. The electroslag voltage between anode end and liquid steel is applied to control the depth of anode end in the slag layer during the refining process with this ladle furnace.

关键词： ladle furnace secondary refining DC electroslag

SHRIMP dating of the Bangong Lake SSZ-type ophiolite: Constraints on the closure time of ocean in the Bangong Lake-Nujiang River,northwestern Tibet

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chinese science Bulletin 2007年第7期52卷 936-941页

作者： shi RenDeng1,2 1 school of Earth and Space sciences, university of science and technology of china, Hefei 230026,{4. 2 Institute of Geology, chinese academy of Geological sciences, beijing 100037,{4. (email: shird@***) school of Earth and Space sciences University of Science and Technology of China Hefei China Institute of Geology Chinese Academy of Geological Sciences Beijing China

The Bangong Lake ophiolite is located in the westernmost part of the Bangong Lake-Nujiang River suture zone. It is a tectonic mélange consisting of numerous individual blocks of peridotite, pillowed and massive lavas and mafic dykes with SSZ-type ophiolitic geochemical affinity formed at the end of a Wilson circle. The SHRIMP U-Pb ages of the co-magmatic zircon domains from one gabbroic dyke (Sample 01Y-155) range from 162.5±8.6 Ma to 177.1±1.4.Ma with an average of 167.0±1.4.Ma (n = 12, MSWD = 1.2), suggesting that the subduction of the Bangong Lake Neo-Tethyan Ocean started before the Middle Jurassic. It is inferred that the tectonic transform from spreading to subduction of the Neo-Tethyan Ocean began before the Middle Jurassic in the Bangong Lake area.

关键词：西藏班公湖怒江缝合带古海洋闭合时期 SSZ型蛇绿岩 SHRIMP 测年