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Calculating model of mass action concentrations for Ag-Au-Cu melts

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Rare Metals 2002年第1期21卷 43-47页

作者： ZHANG Jian Metallurgy school, university of {2. and Technology beijing, beijing 100083, china Metallurgy school University of Science and Technology Beijing 北京 100083

Based on phase diagrams and measured activities, the calculatingmodel of mass action concentrations for het- erogeneous meltsAg-Au-Cu was formulated. Calculated results agree with the improvedresults of recent research work, Showing that the model formulatedcan reflect the structural characteristics of these melts. In thismodel, without the help Of any empirical parameters, only threeequilibrium constants are used, hence it is simple, lear, andfavorable to the sim- Plification of calculation.

关键词： activity mass action concentration eutectic Solid solution

Microstructural Features During Strain Induced Ferrite Transformation in 08 and 2.Mn Steels

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Journal of university of science and Technology {2. 2001年第2期8卷 105-110页

作者： Ping Yang, Feng-e Cui, Fuming Wang (materials science and Engineering {2., university of science and Technology beijing, beijing 100083, china) (Metallurgy {2., university of science and Technology beijing, beijing 100083, china) Univ Sci & Technol beijing Mat Sci & Engn Sch Beijing 100083 Peoples R China Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China

The microstructure evolution during strain induced ferrite transformation was followed in thermal-simulation tests of clean 08 and 2.Mn steels. The influences of carbon equivalence and initial austenite grain size on ferrite grain refinement and the volume fraction of ferrite during straining were inspected. The results revealed that the accelerating effect of ferrite transformation by strain was increased as the carbon equivalence decreased. However, finer ferrite grains were obtained at higher carbon content. At strain of similar to1.5 ferrite grains less than 3 mum and 2.mum can be obtained in 08 and 2.Mn steels respectively. Whereas the ferrite grain refinement in 08 steel was due to both effects of strain induced transformation and ferrite dynamic recrystallization, that in 2.Mn was mainly due to strain induced transformation. Heavy strain can produce fine ferrite grains in coarse austenite grained 08 steel, but it would lead to band microstructure in coarse austenite grained 2.Mn.

关键词： clean carbon steel strain induced transformation grain refinement ferrite dynamic recrystallization

Calculating Model of Mass Action Concentrations for Mn-C Melts and Optimization of Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and materials 1998年第4期12卷 208-211页

作者： Jian Zhang(Metallurgy school, university of {2. and Technology beijing, beijing 100083, china) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagram, the coexistence theory of the metallic melt structure involving compoundformation and the regularity of melts containing saturated phase, a calculating model of mass action concentrationsfor Mn-C melts was formulated. According to the activities (or activity coefficients AM. and γc.), obtained by theUnified Interaction Parameter Model (UIPM), the thermodynamic parameters G and G at higher temperatures (162.～1873 K) were optimized by the repeated try and error method. It is testified that G G(873～12.3 K) and G (2.8～162. K), obtained at lower temperatures, can also be used at the above-mentionedhigher temperatures. The calculated N. and N agree well with ac. and ac obtained by UIPM. This result showsthat the deduced model can reflect the structural reality of Mn-C melts.

关键词： Mn-C melts activity coexistence theory mass action concentration

Calculating Models of Mass Action Concentrations for Ni-Mn and Co-Mn Melts and Optimization of Their Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and materials 2000年第4期14卷 246-250页

作者： Jian Zhang (Metallurgy school, university of {2. and Technology beijing, beijing 100083, china) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

According to phase diagrams, measured activities as well as the coexistence theory of motallic melts structure involving compound formation, the calculating models of mass action concentrations for Ni-Mn and Co-Mn melts are formulated and their thermodynamic parameters are optimized. As a result, the calculated mass action concentrations agree well with the corresponding measured activities, showing that these models can reflect the structural characteristics of both Ni-Mn and Co-Mn melts.

关键词： activity metallic melts coexistence theory mass action concentration

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 {2., university of science and Technology beijing, beijing 100083, china material science and Engineering {2., Wuhan university of science and Technology, Wuhan 430 material science and Engineering {2. University of Science and Technology Beijing Beijing 100083 China material science and Engineering {2. 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

Sticking-up Behaviors and Surface Friction of IF Electrogalvanized Sheet Steel in Forming

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International Journal of Minerals,Metallurgy and materials 1999年第1期13卷 61-63,68页

作者： Jiming Hu Jixun Wu Yanping Lu Yanrong Zhu (material science and Engineering {2., university of science and Technology beijing, beijing 100083, china) Univ of science and Technology Beijing Beijing China

X-ray diffraction (XRD), ball-disc friction and wearing machine and draw-bead test were introduced to investigat the strcusture and workability of IF sheet steel electrogalvanized deposits prepared from sulphate solution system. It was shown that the picking-up of the zinc coating on die strengthened with the increasing of friction factor which was originally affected by the coating's structure. Duing forming, (00X) planes (X= 2. 4) preferential orientation of zinc deposits increased, which resulted in enhanc ing the coating's friction behaviors. Therefore, the forming mechanism of electrogalvedzed deposit was demonstrated that both friction and the stricking -up behaviors of the coating are intensified simultaneously and affect each other.

关键词： electrogalvanized deposit forming friction factor

Nonclassical Plane-crystallographic Groups and Their Applications IV

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International Journal of Minerals,Metallurgy and materials 1998年第4期12卷 228-232页

作者： Lequan Min Xaodan zhang(Applied science school, school,university of science and Technology beijing, beijing 100083,china) Applied science school University of Science and Technology Beijing Beijing 100083 China

Eight kinds of nonclasslcal periodic lattices with locally 8-fold rotational symmetries are *** can be described via nonclassical Planc-crystallographic groups. The periodic lattices may be interpreted bythe projections on the plane of the corresponding unit cells consisting of embedding polyhedrons, respectively. TheFourier-transform patterns of the Periodic lattices have striking approximate'8-fold rotational symmetries', some ofwhich are similar to those displaying in the electrton-diffraction patterns of so-called quasicrystals.

关键词： nonclasslcal crystallographic groups locoally 8-fold symmetry Fourier-transform patterns, quasicrystals

A Back Look on the Binary Phase Diagrams of Metals from the Mass Action Law and the Coexistence Theory of Metallic Melts

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Journal of university of science and Technology {2. 2001年第1期8卷 15-19页

作者： Jian Zhang Metallurgy school, university of {2. and Technology beijing, beijing 100083, china Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China

According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi-Tl and Ni-Al melts involving compound formation have been calculated. The calculated results show that, except the ultimate case of pure element, when two elements are present in the melts, all structural units (atoms and molecules) without exception will be present in the melts, i.e., their concentrations may change from great to small, but they will not vanish into nothing, and only under such conditions, the calculated results both agree with practice and obey the law of mass action. In view of that over considerable wide composition range, the activities of both elements of the three solid binary alloys mentioned above have been measured, this seems in contradiction with the present relevant phase diagrams, in which the structural units are determined by composition range, so the latter needs further investigation and consideration.

关键词： activity phase diagram the mass action law the coexistence theory

Calculating Models of Mass Action Concentrations for Fe-P and Cr-P Melts and Optimization of Their Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and materials 1999年第3期13卷 174-177页

作者： Jian Zhang(Metallurgy school, university of {2. and Technology beijing, beijing 100083, china) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagrams, reliable reference experimental data and the coexistence theory of metallic melts structure involving compound formation, calculating models of mass action concentrations for Fe-P and Cr-P melts have been formulated. At the same time, some of their thermodynamic parameters have been optimized. The calculated results not only agree well with the measuredvalues, but also obey the mass action law rigorously, this in turn shows that these models can reflect the structural characteristics of corresponding melts.

关键词： activity phase diagram coexistence theory mass action concentration