MATHEMATICAL-MODELING OF TRANSFORMATION IN NB MICROALLOYED STEELS

被引：35

作者：

LEE, KJ

LEE, JK

KANG, KB

KWON, O

机构：

[1] Steel Products Department, Research Institute of Industrial Science and Technology, Pohang

来源：

ISIJ INTERNATIONAL | 1992年 / 32卷 / 03期

关键词：

NB STEELS; PHASE TRANSFORMATION; THERMODYNAMIC CALCULATIONS; DIFFUSIONAL GROWTH KINETICS;

D O I：

10.2355/isijinternational.32.326

中图分类号：

TF [冶金工业];

学科分类号：

0806 ;

摘要：

Thermodynamic and kinetic modelling was performed to describe the decomposition of austenite and the precipitation of alloy carbides in Nb microalloyed steels. Phase analysis of the Fe-C-Mn and the Fe-C-Nb systems was carried out considering local equilibrium and paraequilibrium, their nucleation behavior (matrix/grain boundary) and the shear energy during transformation. From the analysis, equilibrium transformation temperatures of each phase, the Gibbs energy changes for nucleation and compositions of elements at the phase boundary were derived. The transformation kinetics were formulated using classical nucleation and growth theories. Both local equilibrium and para-equilibrium conditions were considered to evaluate the partitioning of Mn during growth. The calculated TTT, CCT diagrams and the volume fraction of each phase were compared with the experimental results, and the most probable behaviors of gamma/alpha transformation and NbC precipitation in Nb steels were discussed.

引用

页码：326 / 334

页数：9

共 35 条

[21] THE KINETICS OF FERRITE NUCLEATION AT AUSTENITE GRAIN-BOUNDARIES IN FE-C ALLOYS [J].

LANGE, WF ;

ENOMOTO, M ;

AARONSON, HI .

METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 1988, 19 (03) :427-440

[22] PRECIPITATE NUCLEATION KINETICS AT GRAIN-BOUNDARIES [J].

LANGE, WF ;

ENOMOTO, M ;

AARONSON, HI .

INTERNATIONAL MATERIALS REVIEWS, 1989, 34 (03) :125-150

[23]

LEE BJ, 1989, CALPHAD, V13, P355, DOI 10.1016/0364-5916(89)90025-4

[24]

Lee K. J., 1990, P INT C MATH MOD HOT, P435

[25] ON EVALUATION OF THE EQUATIONS FOR THE GROWTH-KINETICS OF ELLIPSOIDAL PRECIPITATES [J].

MENON, ESK ;

HYLAND, RW ;

AARONSON, HI .

SCRIPTA METALLURGICA, 1984, 18 (04) :367-370

[26]

NANBA S, 1990, CAMP ISIJ, V3, P871

[27] CALCULATION OF THE FE-C-NB TERNARY PHASE-DIAGRAM [J].

OHTANI, H ;

HASEBE, M ;

NISHIZAWA, T .

CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY, 1989, 13 (02) :183-204

[28]

Ohtsuka H., 1988, THERMEC 88, P352

[29]

Okaguchi S., 1988, THERMEC 88, P330

[30]

Priestner R., 1973, Metal Science Journal, V7, P60

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