Precipitation of Niobium Carbonitrides: Chemical Composition Measurements and Modeling


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High Resolution Transmission Electron Microscope and Electron Energy Loss Spectroscopy and have been used to characterize the structure and chemical composition of niobium carbonitrides in the ferrite of a Fe-Nb-C-N model alloy at different precipitation stages. Experiments seem to indicate the coexistence of two types of precipitates: pure niobium nitrides and mixed sub-stoichiometric niobium carbonitrides. In order to predict the chemical composition of these precipitates, a thermodynamical formalism has been developed to evaluate (i) the nucleation and growth rates (classical nucleation theory) and (ii) the chemical composition of nuclei and existing precipitates. A model based on the numerical resolution of former equations, is used to compute precipitates size distribution evolution at a given temperature. The predicted compositions are in very good agreement with experimental results.



Materials Science Forum (Volumes 539-543)

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Edited by:

T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran




M. Perez et al., "Precipitation of Niobium Carbonitrides: Chemical Composition Measurements and Modeling", Materials Science Forum, Vols. 539-543, pp. 4196-4201, 2007

Online since:

March 2007




[1] E. J. Palmiere, C. I. Garcia and A. J. Deardo, Metall. Mater. Trans. 27A-4 (1996) pp.951-960.

[2] C. Fossaert, G. Rees, T. Maurickx and H. K. Badeshia, Metall. Mater. Trans. 26A (1995) pp.21-30.

[3] W. M. Rainforth, M. P. Black and F. Hofer, Acta Mat. 50 (2002) pp.735-747.

[4] R. Kampmann and R. Wagner, Second phase precipitation in Materials Science and Technology: A Comprehensive Treatment, VCH, Weinheim, vol. 5 (1991) pp.213-304.

[5] H. R. Schercliff and M. F. Ashby, Acta Mater. 38 (1990) pp.1789-1812.

[6] A. Deschamps, Y. Brechet, Acta Mater. 47 (1999) pp.293-305.

[7] O. R. Myhr, O. Grong, Acta Mater. 48 (2000) pp.1605-1615.

[8] M. Perez, A. Deschamps, Mater. Sci. Eng. A360, (2003) pp.214-219.

[9] P. Maugis and M. Gouné, Acta Mater. 53 12 (2005) pp.3359-3367.

[10] F. Hofer, P. Warbichler, B. Buchmayr and B. Kleber, J. of Micr. 184 3(1996) pp.163-174.

[11] A. J. Craven, K. He, L. A. Gravie and T. N. Baker, Acta Mater. 48, (I) pp.3857-3868 and (II) pp.3869-3878.

[12] J. A. Wilson and A. J. Craven, Ultramicroscopy 94 (2003) pp.197-207.

[13] M. Beres, T. E. Weirich, K. Hulka and J. Mayer, Steel Research Int. 75 (2004) pp.753-758.

[14] C. P. Scott, D. Charleix and P. Barges, Scripta Mater. 47 (2002) 845-849.

[15] E. Courtois, PhD Thesis, INSA-Lyon, France (2005).

[16] E. Courtois, T. Epicier and C. Scott, Micron, In press.

[17] E. Bemont, PhD Thesis, University of Rouen, France (2003).

[18] M. Hillert and L. I. Staffansson, Acta Chemica Scandinavia 24 (19970) pp.3618-3626.

[19] D. Acevedo and M. Perez, Computational Mater. Sc. Submitted.

[21] T. Gladmann, The physical Metallurgy of Microalloyed Steels, Inst. Mater., London (1997).

[22] R. C. Hudd, A. Jones and M. N. Kale, J. Iron Steel Inst. 209 (1971) p.121.