Study on the Diffusion Coefficient in NGS under Low Tensile Stress

Abstract:

In this paper, the diffusion coefficient of vacancy-solute complex and diffusion coefficient of solute atoms, P, in non-equilibrium grain-boundary segregation under low tensile stress in steel 12Cr1MoV are calculated based on the model developed by Xu. Both the simulation and experimental kinetics curves are achieved. Results show that the calculated result with the kinetic equations perfectly fits with the experimental observations for phosphorus in steel 12Cr1MoV under low tensile stress. In the segregation process, the rate of phosphorus segregation is high due to a large diffusivity of the complex. In the de-segregation process, the level of phosphorus segregation decreases with increasing stress aging time. But the rate of phosphorus desegregation from grain boundaries to centre is slower compared with that in segregation for the diffusion coefficient of phosphorus atoms is far lower than the complexes.

• Periodical: Key Engineering Materials (Volumes 525-526)
• Pages: 317-320
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.525-526.317
• Online since: November 2012
• Authors: Ying Jie Qiao, Hong Bo Fu, Chun Kai Li
• Keywords: Diffusion Coefficient, Low Tensile Stress, Non-Equilibrium Grain-Boundary Segregation (NGS), Phosphorus

References

[1] T. D. Xu, Progress in Materials Science, 49 (2004) 109.

[2] T. D. Xu, Scipta Materialia. Vol. 46 (2002), P. 759-763.

[3] T. D. Xu, Journal of Materials Science. Vol. 35 (2000), P. 5621- 5628.

[4] Shinoda T, Nakamura T. Shinoda T, ed. Acta Metal. Vol. 29 (1981), P 1631.

[5] Misra. R. D. K. Acta Mater. Vol. 44 (1996), P. 885-890.

[6] Misra. R. D. K. Scripta Mater. Vol. 35 (1996), P. 755-760.

[7] T. D. Xu, S. H. SongActa Matall. Vol. 37 (1989), P. 2499.

[8] Y. D. Fu, Key Engineering Materials, Vols. 353-358 (2007) pp.396-399.