李扬
,
程树森
,
蔡皓宇
钢铁研究
通过热力学计算,研究了高炉中钛氧化物的还原过程,分析了TiC、TiN在高炉风口回旋区、渣铁层及铁水中的生成和转移,并得到了Ti(C,N)在渣铁界面析出时的炉渣中TiO2的临界质量分数.利用Factsage软件计算分析了渣铁平衡时铁水中w(Ti)与w(Si)之间的相互关系,发现:w(Si)、w(Ti)及w(Si) /w(Ti)的值在炉渣成分不改变的情况下会随温度的升高而增大;炉渣碱度0.9~1.2,炉渣w(TiO2)在5.5%以下时,铁水中的w(Ti)会随碱度升高而增加;在炉缸温度一定时,炉缸中Ti(C,N)的生成依赖于渣中w(TiO2).
关键词:
热力学
,
Ti (C,N)生成
,
临界w(TiO2)
,
护炉
Shuigen HUANG
,
Lin LI
,
O.V.D.Biest
,
J.Vleugels
,
Peiling WANG
材料科学技术(英文)
Using compound energy model (CEM), the thermodynamic properties of and were evaluated. The evaluation was based on the optimization of ZrO2-CeO2 and ZrO2-CeO1.5 systems, as well as the miscibility gap in CeO1.5-CeO2 system. Except the cubic fluorite structure phase assessed with compound energy model, all the other solution phases were assessed with subsitutional solution model. The model parameters were evaluated through fitting the selected experimental data by means of thermodynamic optimization. A set of parameters with thermodynamics self-consistency was obtained and satisfactorily described the complex relation between y in and the partial pressure of oxygen at different temperatures, also the interdependence among miscellaneous factors such as temperature, oxygen partial pressure, the reduction amount of CeO2 as well as the nonstoichiometry in cubic phase . The calculated results seem to be reasonable when put into the explanation of pressureless sintering of CeO2-stabilized ZrO2 powder compacts at a controlled oxygen partial pressure.
关键词:
Zirconia
,
null
,
null
,
null
Xingqiu CHEN
,
Hailan LI
,
Xueyong DING
,
P.Rogl
,
P.Podloucky
材料科学技术(英文)
The improved form of calculation formula for the activities of the components in binary liquids and solid alloys has been derived based on the free volume theory considering excess entropy and Miedema's model for calculating the formation heat of binary alloys. A calculation method of excess thermodynamic functions for binary alloys, the formulas of integral molar excess properties and partial molar excess properties for solid ordered or disordered binary alloys have been developed. The calculated results are in good agreement with the experimental values.
关键词:
Binary alloy
,
null
,
null
,
null
Lin LI
,
B.C.De Cooman
,
P.Wollants
,
Yanlin HE
,
Xiaodong ZHOU
材料科学技术(英文)
With the sublattice model, equilibrium compositions of ferrite (α) and austenite (γ ) phases, as well as the volume percent of austenite (γ) at 780℃ in different TRIP steels were calculated. Concentration profiles of carbon, Mn, Al and Si in the steels were also estimated under the lattice fixed frame of reference so as to understand the complex mechanical behavior of TRIP steels after different isothermal bainitic transformation treatments. The effect of Si and Mn on transformation induced plasticity (TRIP) was discussed according to thermodynamic and kinetic analyses. It is recognized that Al also induces phase transformation in the steels but its TRIP effect is not as strong as that of Si.
关键词:
Equilibrium composition
,
null
,
null
,
null