Lin LI
,
B.C.De Cooman
,
P.Wollants
,
Yanlin HE
,
Xiaodong ZHOU
材料科学技术（英）
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
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null
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Weiyan LÜ
,
Lin LI
,
Li WANG
,
Yanlin HE
,
Shuigen HUANG
材料科学技术（英）
Phase diagram information of the Fe-C, Fe-Al and Al-C systems are reviewed and the Fe-Al-C system is assessed. A FeAlC database is created by combining a set of thermodynamic parameters established by Kumar and SSOL database in Thermo-Calc software package. Ternary phase diagrams are calculated with FeAlC and the newly developed Thermo-Calc databases SSOL2 and SSOL4. The FeAlC database is the best one to describe the Fe-Al-C system. A1 and A3 values on the vertical section containing 1.5 wt pct Al are calculated with the FeAlC database in this work. To validate the thermodynamic calculation, critical temperatures Ac1 and Ac3 are determined by using dilatometer analysis. There exist some errors between the calculated values and the experimental results. So further optimization of the Fe-Al-C system regarding bcc and fcc phases is necessary. The experimental data in this work could be of some value in further optimization.
关键词:
Fe-Al-C
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null
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