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Journal of University of science and technology beijing 2002年第4期9卷 282-286页

作者： Maicang zhang, Jianxin Dong, Yanping Zeng, Xishan XieMaterials science and engineering {3., University of science and technology beijing, beijing 100083. china Mat. Sci. and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The flow behavior of Rene 95 PM alloy was studied from 1050 to 1150 deg Cwith strain rate of 1 X 10^(-3., 1 X 10^(-2), 1 X 10^(-1) and 1 s^(-1). At a given temperature andstrain rate, flow curves exhibit a peak followed by flow softening up to a steady state. Moreover,at constant strain, flow stress increases with increasing strain rate and decreasing temperature. Anequation relating hyperbolic sine of flow stress to hot working parameters, such as strain, strainrate and temperature, was established by using multiple nonlinear regression method. A very goodagreement was found between predicted and experimental flow stress in all the strain rangeinvestigated. Application of the constitutive equation in predicting forming loads and flow behaviorand temperature distribution in both upper and lower dies in an isothermal forging process ofturbine disk of large dimension (about 63. mm) by means of a finite element code was systematicallyanalyzed.

关键词： constitutive equation finite element method isothermal forging Rene 95PM alloy

Numerical prediction of the incremental melting and solidification process

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Journal of University of science and technology beijing 2003年第4期10卷 50-54页

作者： Jun Wang, Chengchang Jia, and Sheng YinMaterials science and engineering school, University of science and technology beijing, beijing 100083. china Mat. Sci. and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

A mathematical formulation is applied to represent the phenomena in theincremental melting and solidification process (IMSP), and the temperature and electromagneticfields and the depth of steel liquid phase are calculated by a finite difference technique using thecontrol volume method. The result shows that the predicted values are in good agreement with theobservations. In accordance with the calculated values for different kinds of materials anddifferent size of molds, the technological parameter of the IMS process such as the power supply andthe descending speed rate can be determined.

关键词： incremental melting and solidification process (IMSP) numerical prediction electromagnetic field temperature field technological parameter

ESKD-A New Structure of Expert System Based on Knowledge Discovery

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 63-71页

作者： Bingru Yang Fasheng liu Jiangtao Shen Information engineering school, University of science and {3. beijing, beijing, 100083. china Information engineering school University of Science and Technology Beijing Beijing 100083 China

A new structure of ESKD (expert system based on knowledge discovery system KD (D&K)) is first presented on the basis of KD (D&K)-a synthesized knowledge discovery system based on double-base (database and knowledge base) cooperating mechanism. With all new features, ESKD may form a new research direction and provide a great probability for solving the wealth of knowledge in the knowledge base. The general structural frame of ESKD and some sub-systems among ESKD have been described, and the dynamic knowledge base based on double-base cooperating mechanism has been emphased on. According to the result of demonstrative experi- ment, the structure of ESKD is effective and feasible.

关键词： knowledge discovery expert system dynamic knowledge base, double-base cooperating mechanism

Mass transfer coefficients in metallurgical reactors

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Journal of University of science and technology beijing 2003年第2期10卷 1-9页

作者： Ying QuMetallurgical engineering school, University of science and {3. beijing, beijing 100083. china Univ Sci & Technol beijing Met Engn Sch Beijing 100083 Peoples R China

An overview on the application and achievements of physico-mathematicalmodeling of metallurgical processes in china is briefly declared. The important role of coefficientsin model formulation is shown from our experience. The mass transfer coefficients of the slag-metalreactions and the gas-metal reactions are discussed referring to the flow conditions near theinterface. The influence of the surface-active species on the mass transfer and the interfacialreaction is also discussed briefly.

关键词： mass transfer modeling pyrometallurgy reaction engineering interfacial flow stirring power

Thermodynamic Properties of Mn-P and Fe-Mn-P Melts

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 10-13页

作者： Jian zhang Rong Zhu Metallurgy school, University of science and {3. beijing, beijing 100083. china Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China

Based on the phase diagrams and the coexistence theory of metallic melts structure involving compound formation, the cal- culating models of mass action concentrations for Mn-P and Fe-Mn-P melts have been formulated. The calculated mass action concen- trations agree well with the corresponding measured activities, this in turn shows that the deduced models can reflect the structural char- acteristics of the melts concerned and there isn't any saturation of phosphorus in both melts.

关键词： activity dephosphorization the coexistence theory mass action concentration

Change Laws of Flake's Temperature during Making a Diamond Film by DC-PJ

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 97-102页

作者： Xuhong Chen Lihe Zhao Fanxiu Lu(Mechanical engineering school, University of science and {3. beijing, beijing 100083. china) Mechanical engineering school University of Science and Technology Beijing Beijing 100083 China

When making a diamond film by direct current plasma jet, a kind piece of flake is used as a base body Which the film can beattached to. The flake's temperature is unstable. Therefore, some experiments and constructed mathematical models, which were solvedby computer, were done. The results show that the flake's temperature is influenced by many factors and the mains are plasma jet powerand vacuum pressure. Through adjusting the two parameters, the flake's temperature can be accurately controlled, furthermore, diamondfilms' quality would be improved. Lowering sediment platform's temperature has a little effect to the flake's temperature at present technology conditions.

关键词： CVD (Chemical Vapor Deposition) plasma, impact heat transfer

NONEL High Precision MS Delay Detonator

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Journal of University of science and technology beijing 2001年第3期8卷 164-166页

作者： Daze Lin, Peng Yang Civil and Environmental engineering school, University of science and {3. beijing, beijing 100083. china Univ Sci & Technol beijing Sch Civil & Environm Engn Beijing 100083 Peoples R China

The NONEL high precision MS Delay Detonator (FDG-1detonator) is introduced. The main aspects about the FDG-1 detonator include the choice of structure, delay composition, control of the gas chamber, optimum charge and density, suitable explosives per meter in the NONEL tube, base firing charge and the main specifications. The improvement of the characteristics of FDG-1 detonator has been tested systematically. The testing method is reliable and its precision can meet the demand for usage.

关键词： NONEL high precision MS Delay Detonator delay time

A Fuzzy Model for Evaluating the Mining Condition of Underground Coal Mines

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 242-245页

作者： Zhongrue Li Shaowen zhang(Resources engineering school, University of {3. and technology beijing, Beding 100083. china) Resources engineering school University of Science and Technology Beijing Beijing 100083 China

In mining industries no mines are identical and each mine has its own unique set of mining conditions. In order to study thecondition of mines for efficiency, safety and economy reasons, a fuzzy model is presented based on fuzzy evaluation. Relevant data fromfive mines were collected and the model was used to evaluate the mining condition of these mines. The evaluation results are in conformity with the real situation.

关键词： fuzzy model mining condition coal mine

Behaviors of fine bubbles in the shroud nozzle of ladle and tundish

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Journal of University of science and technology beijing 2003年第4期10卷 20-23页

作者： Yanping Boo, Jianhua Liu, and Baomei XuMetallurgical engineering school, University of science and {3. beijing, beijing 100083. china Metall. Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Fine bubbles will create when the inert gas is introduced to the high rapidsteel stream within the shroud nozzle between ladle and tundish. The collision and attachment amongthe bubbles and fine inclusions will promote the floatation efficiency of inclusions in the *** behaviors of the bubbles, such as the dispersion in shroud, coalescence and floatation intundish, are studied. The results show that the maximum sizes of the bubbles in the water and steelflow within the shroud in the length of 1.2 m are 0.70-1.44 mm and 1.53.3.16 mm respectively whenthe flow rates are 0.006-0.016 m^3.s; the terminal velocities of fine bubbles in the water andmolten steel within the tundish are 0.02-0.2 and 0.05-0.6 m/s.

关键词： fine bubbles shroud nozzle of the ladle flotation

The mathematical model of wetting angle of heterogeneous nucleation

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science china(Technological sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2 & ZHAO Pei3.1. school of Metallurgical and Ecological engineering, University of science and {3. beijing, beijing 100083. china 2. school of Material science, University of science and {3. beijing, beijing 100083. china 3. Central Iron and Steel Research Institute, beijing 100081, {13. 1. school of Metallurgical and Ecological engineering University of Science and Technology Beijing 100083 Beijing China 2. school of Material science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and Steel Research Institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2O3.are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.