工程科學學報

1992, 14(6): 1-2. doi: 10.13374/j.issn1001-053x.1992.06.001

[Abstract](193) [PDF 197KB](7)

Abstract:

Calculation of the RECl₃-SrCl₂-LiCl Ternary Phase Diagram Systems

Qiao Zhiyu, Xing Xianran, Zheng Chaogui, Duan Shuzhen

1992, 14(6): 599-606. doi: 10.13374/j.issn1001-053x.1992.06.002

[Abstract](295) [PDF 529KB](9)

Abstract:
Based on the optimization and assesment of nine sub-binary phase diagrams and their thermodynamic data:RECl₃-SrCl₂, RECl₃-LiCl, SrCl₂-LiCl (RE:La,Ce,Pr,Nd),the relevant ternary thermodynamic properties of RECl₃-SrCl₂-LiCl systems are predicted and criticized. Using Toop approximation, four ternary phase diagams of the RECl₃-SrCl₂-LiCl systems are calculated. Their results are briefly discussed.

Calculation the Activities from Binary Systems Containing Congruently Melting Compounds Using Their Melting Enthalpy

Li Xingkang, Liu Sijun, Wang Jian, Li Wenchao

1992, 14(6): 607-611. doi: 10.13374/j.issn1001-053x.1992.06.003

[Abstract](282) [PDF 423KB](7)

Abstract:
A new method of calculating activities from binary systems has been developed. The new formulae require that the phase diagrams must contain congruently melting compound and its melting enthalpy is known. Their feasibility is tested by applying the new formulae to In-Sb system. By this method, the activities of an important semi-conductor system Ga-As have also been predicted.

Modified Quasichemical Theory and Its Application in the System of KCl-YCl₃

Qiao Zhiyu, Zhuang Weidong

1992, 14(6): 612-617. doi: 10.13374/j.issn1001-053x.1992.06.005

[Abstract](296) [PDF 476KB](11)

Abstract:
The modified quasichemical theory for the thermodynamic analysis with its optimization method has been introduced. Optimization and calculation computer programs have been developed. By using these programs, the phase diagram and thermodynamic data of the KCl-YCl₃ system have been optimized.

Calculation Activities from Binary Phase Diagrams Using the Standard Enthalpy of Formation

Liu Sijun, Li Xingkang, Wang Jian, Li Wenchao

1992, 14(6): 618-621. doi: 10.13374/j.issn1001-053x.1992.06.006

[Abstract](294) [PDF 297KB](10)

Abstract:
The accurate formula has been derived based on the previous approximate one. Using this new formula, the activties of In-Sb were calculated. The Calculated results were in accord with the experimental data, that shows reliability of the formula.

Calculation of Activities from Phase Diagrams Involving Solid Solution

Cai Wenjuan, Zhang Fan, Xie Fanyou, Zhou Guozhi

1992, 14(6): 622-628. doi: 10.13374/j.issn1001-053x.1992.06.007

[Abstract](356) [PDF 499KB](17)

Abstract:
The Analytical expressions for calculating and activity coefficients at a fixed temperature from phase diagrams involving equilibrium between solid and liquid solutions are derived. In the expressions, activities and activity coefficients are functions of the composition. These expressions are applied to system Ag-Pb, and the results are efficient.

Stability of A Determination of Intermediate Compound Standard Gibbs Free Energy of Formation

Liu Sijun, Li Xingkang, Wang Jian, Li Wenchao

1992, 14(6): 629-636. doi: 10.13374/j.issn1001-053x.1992.06.008

[Abstract](330) [PDF 453KB](9)

Abstract:
Based on principles of thermodynamics, it is derived that: in a binary system, a quasi-parabola regulation must be obeyed by the standard Gibbs free energy of formation of compound. Extended to ternary systems, a quasi-paraboloid regulation also is done. The stabilities of intermediate compound in binary systems containing a rare earth element are criticized.

New Asymmetric Geometric Model for Predicting Ternary Thermodynamic Properties

Xing Xianran, Qiao Zhiyu, Zheng Qigui, Duan Shuzhen

1992, 14(6): 637-643. doi: 10.13374/j.issn1001-053x.1992.06.009

[Abstract](275) [PDF 509KB](7)

Abstract:
A new geometric asymmetric model for predicting t thermodynamic properties of ternary system from three sub-binaries is presented. Its analytical expression with good calculating accuracy is most simple in present asymmetric models. The new model was applied to predict the enthalpies of mixing of the Bi-Ga-Sn, Au-Ag-Sn and NaCl-KCl-CaCl₂ ternary systems which were in good agreements with experimental data. At present work, based on thermodynamic principles, the importance of the choice of symmetric component is also discussed.

Calculation of Activities from Phase Diagrams Involving Intermediate Compounds

Xie Fanyou, Zhang Fan, Cai Wenjuan, Zhou Guozhi

1992, 14(6): 644-649. doi: 10.13374/j.issn1001-053x.1992.06.010

[Abstract](390) [PDF 455KB](21)

Abstract:
A new method for calculating activities and activity coefficients of components from phase diagram at a fixed temperature is introduced. Analytical expressions for the calculation of activities are presented, in which activities of components are functions of the composition. The application of the expressions to Mg-Sn system shows that this method is efficient.

Effect of A Little Oxygen in Solid Solution on the Relative Stability Between α-Ti and β-Ti Phases

Xia Haiping, Chen Guoliang, Ni Kequan

1992, 14(6): 650-654. doi: 10.13374/j.issn1001-053x.1992.06.011

[Abstract](281) [PDF 345KB](7)

Abstract:
The activity coefficient of Titanium in α-Ti and β-Ti phases were obtained from Ti-O binary phase diagram and some relative thermochemical data. Further, the effect of oxygen, which was quite a few amount and dissolved in Titanium, on the relative stability between α-Ti and β-Ti was discussed. The difference of Ti-Al binary phase diagrams among different author's experimental's was explained qualitatively.

The E-pH Relationship of Metal-H₂O Systems with Several Kinds of Ions in Equilibrium

Li Zhangrong, Zhang Weijing

1992, 14(6): 655-659. doi: 10.13374/j.issn1001-053x.1992.06.012

[Abstract](257) [PDF 389KB](35)

Abstract:
The Principle of simultaneous equilibrium is applied to the Fe-H₂O and the Cu-H₂O systems. The potential-pH relations between solutions and solid species are calculated in the certain potential ranges. The results are more conformable to practical conditions. This method is applicable to calculating the potential-pH relationship of Metal-H₂O system with several kinds of ions in equilibrium.

Computer Simulation for the Phase Analysis of High Speed Steels

Song Qi, Shen Baolian, Yu Yongning, Zhang Weijing

1992, 14(6): 660-666. doi: 10.13374/j.issn1001-053x.1992.06.013

[Abstract](277) [PDF 493KB](5)

Abstract:
The foundation of the computer simulation for the phase analysis of alloys vising phase e-quilibrium calculation has been expounded. The phases presented in the microstructure of W6Mo5Cr4V2, W10Mo4Cr4V3Al and Mo5Cr4V high speed steels at the quench-heated state and the anneal-heated state have been analyaed differently, and the necessary information concerning the phase constituents in the steels at the states mention above and their variation has been obtained.

Calculation of γ-α Nuclear Driving Forces and Critical Nucleus Compositions of Alloy Steel

Guo Hong, Yu Yongning

1992, 14(6): 667-671. doi: 10.13374/j.issn1001-053x.1992.06.014

[Abstract](310) [PDF 397KB](11)

Abstract:
On the basis of Wagner's kinetic model, the compositions of critical nucleus and the nuclear driving forces of the precipitation of preutectoid ferrite in the conditions of equilibrium and para-equilibrium for polynary low-alloy steels, containing Mn, Si, Ni, Cr, Mo, Cu, V, Nb, W and Co (the total content<7%), were calculated. A pratical calculated programme was established.

Calculation of Fe-C Base Alloy Ternary Phase Diagrams

Chen Weiqing, Du Zhenmin, Wu Ping, Zhang Weijing

1992, 14(6): 672-676. doi: 10.13374/j.issn1001-053x.1992.06.015

[Abstract](342) [PDF 380KB](13)

Abstract:
The software which calculated the thermodynamic properties of Fe-C base alloy ternary system is designed. It can calculate the isothermal section of Fe-C-M (m=Cr, Mn, Si, Cu, Mo, W, Mi, V, Ti, Nb) system and give related thermodynamic data.

Calculation of the Hardenability Curves of Alloy Steel

Zhang Qizhen, Du Zhenmin, Cheng Lifeng, Zhang Weijing

1992, 14(6): 677-680. doi: 10.13374/j.issn1001-053x.1992.06.016

[Abstract](262) [PDF 316KB](9)

Abstract:
Through calculating the cooling curve of standard top quenching specimen and CCT-diagram, the hardenability curves of alloy steel are calculated.

Calculation of Alloy Steel CCT-Diagram

Xu Jun, Du Zhenmin, Zhang Qizhen, Cheng Lifeng, Zhang Weijing

1992, 14(6): 681-686. doi: 10.13374/j.issn1001-053x.1992.06.017

[Abstract](288) [PDF 429KB](18)

Abstract:
Utilizing experimented TTT-diagram and Avrami equation, the CCT-diagrams of alloy steel are calculated,,

Prediction of the Relationship Between Microstructure and Properties of Hot Worked Alloy Steels

Cheng Lifeng, Du Zhenmin, Zhang Qizhen, Zhang Weijing

1992, 14(6): 687-691. doi: 10.13374/j.issn1001-053x.1992.06.018

[Abstract](221) [PDF 370KB](8)

Abstract:
By utilizing our calculated CCT-diagram, the microstructural distribution on the different cooling schedules is defined. Then the relationship between microstructure and mechanical properties of hot worked alloy steels are predicted.

1992 Vol. 14, No. 6