In the present paper, a numerical modeling was developed to simulate the growth kinetics of ferrite transformed from austenite in Fe-C-∑X (X denotes substitution elements, such as Mn, Ni, Cr etc.) steels by solving the diffusion equation using finite difference method (FDM). Coupled with the kinetic modeling, thermodynamic calculations were carried out to determine the γ/α phase equilibrium conditions using a para-equilibrium (PE) model. The dissipation of free energy for γ→α phase transformation due to the so-called solute drag effect (SDE) was taken into account in the thermodynamic modeling. With this modeling, simulations on the growth kinetics of ferrite in the steels containing austenite-stabilizing and ferrite-stabilizing elements (such as Ni, Mn and Si, Cr, respectively) were performed, which indicates that it deviates from the parabolic growth rate law after the initial stage of transformation. The results were compared with the experimental values given by Bradley and Aaronson, showing that this model has a reasonably good accuracy to predict the growth kinetics of ferrite.
参考文献
[1] | R Zener .[J].Journal of Applied Physics,1949,20:950. |
[2] | M. ENOMOTO .INFLUENCE OF SOLUTE DRAG ON THE GROWTH OF PROEUTECTOID FERRITE IN Fe-C-Mn ALLOY[J].Acta materialia,1999(13):3533-3540. |
[3] | E.Randich;J L Goldstein .[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1975,6:1553. |
[4] | M Kajihara;M Kikuchi .[J].Acta Materialia,1993,41:2045. |
[5] | J Vitek;S A Vitek;S A David .[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1995,26:2007. |
[6] | G. D. Verros;N. A. Malamataris .Finite element analysis of ferrite-austenite diffusion controlled phase transformation[J].Computational Materials Science,2002(3):380-392. |
[7] | J Agren .[J].ACTA MATERIALIA,1982,30:841. |
[8] | J R Bradley;H I Aaronson .[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1981,12:1729. |
[9] | G. Ghosh;G.B. Olson .Precipitation of paraequilibrium cementite: Experiments, and thermodynamic and kinetic modeling[J].Acta materialia,2002(8):2099-2119. |
[10] | J. Miettinen .Simple semiempirical model for prediction of austenite decomposition and related heat release during cooling of low alloyed steels[J].Ironmaking & Steelmaking: Products and applications,1996(4):346-356. |
- 下载量()
- 访问量()
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%