Cite this article:
. . Acta Metall Sin, 2007, 43(10): 1091-1095 .
|
Abstract Proeutectoid ferrite transformation start temperatures (Ar3) with variant continuous cooling rates were measured by dilatometer experiments. A new model, based on ferrite nucleation and growth model, on account of solute drag-like effect of Nb, used to predict Ar3 of Nb-containing low carbon steels, was proposed. It is shown that a limiting carbon concentration in the vicinity of the growing ferrite nuclei is invariable with the variation of temperature, austenite grain size and cooling rate etc, while increases linearly with the Nb content of low carbon steel increasing. Nb content in steels increasing, during the continuous cooling process, results in nuclei temperature of proeutectoid ferrite decreased, while not continue to be decreased when Nb content is more than 0.023 wt pct. Nb solutionized in austenite inhabits the proeutectoid ferrite transformation start. This model is used to predict Ar3 of low carbon steels with Nb content lower than 0.04 wt pct, and the calculated Ar3 is in good agreement with the measured value.
|
Received: 06 February 2007
|
|
[1]Cahn J W.Acta Metall,1956;4:572 [2]Lusk M,Jou H J.Metall Mater Trans,1997;28A:287 [3]Kamat R G,Hawbolt E B,Brown L C,Brimacombe J K. Metall Trans,1992;23A:2469 [4]Militzer M,Hawbolt E B,Meadowcroft T R.Metall Mater Trans,2000;31A:1247 [5]Militzer M,Pandi R,Hawbolt E B.Metall Mater Trans, 1996;27A:1547 [6]Nakata N,Militzer M.ISIJ Int,2005;45:82 [7]Fazeli F,Militzer M.Metall Mater Trans,2005;36A:1395 [8]Xu Z Y.Transformation Theory.Beijing:Science Press, 1988:319 (徐祖耀.相变原理.北京:科学出版社,1988:319) [9]Hawbolt E B,Chau B,Brimacombe J K.Metall Trans, 1985;16A:565 [10]Yuan X Q,Liu Z Y,Jiao S H.ISIJ Int,2006;46:579 [11]Siciliano F,Jonas J J.Metall Mater Trans,2000;31A: 511 [12]Karjalainen L P,Maccagno T M,Jonas J J.ISIJ Int,1995; 35:1523 |
No Suggested Reading articles found! |
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
|
Shared |
|
|
|
|
|
Discussed |
|
|
|
|