Size Distribution of Retained Austenite in Phosphorus-Containing TRIP Steels


Article Preview

The present work investigates the influence of phosphorus addition on the size distribution of retained austenite in TRIP steels containing 0.01%, 0.09% and 0.14% phosphorus. The size of retained austenite is measured by means of neutron depolarization technique and optical microscopy. It is found that the addition of phosphorous increases the size of the larger intergranular and inter-ferritic austenite grains and therefore also increases the volume fraction of retained austenite due to the strengthening effect of phosphorous on the surrounding ferrite and bainite grains. For all phosphorous additions the most frequently observed austenite size is around 0.2 μm, which is probably corresponds to the interlath film-type retained austenite. The average grain size from the neutron depolarization technique agrees in general with that from the optical microscopy and it is suggested that the accuracy can be improved by further development of the data analysis by taking into account the preferred shape and orientation of the austenite grains.



Materials Science Forum (Volumes 539-543)

Main Theme:

Edited by:

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




L. Zhao et al., "Size Distribution of Retained Austenite in Phosphorus-Containing TRIP Steels", Materials Science Forum, Vols. 539-543, pp. 4321-4326, 2007

Online since:

March 2007




[1] L. Zhao, N.M. van der Pers, J. Sietsma and S. van der Zwaag: Mater. Sci. Forum, Vols. 500501 (2005), p.379.

[2] F.D. Fisher, G. Reisner, E. Werner, K. Tanaka, G. Cailletaud and A. Antretter: Inter. J. Plasticity Vol. 16 (2000), Issues 7-8, p.723.

[3] N.H. van Dijk, A. Butt, L. Zhao, J. Sietsma, S.E. Offerman, J.P. Wright and S. van der Zwaag: Acta Mater. Vol. 53 (2005), p.5439.

[4] L. Zhao, F.J. Vermolen, J. Sietsma and S. van der Zwaag: J. Mater. Sci. Techno. Vol. 19 (2003, suppl. 1), p.105.

[5] H.C. Chen, H. Era and M. Shimizu: Metall. Trans. Vol. 20A (1989), p.437.

[6] L. Zhao, T.A. Kop, V. Rolin, J. Sietsma, A. Mertens, P.J. Jacques, S. van der Zwaag: J. Mater. Sci., Vol. 37 (2002), p.1585.


[7] L. Zhao, N.H. van Dijk, E. Brück, J. Sietsma and S. van der Zwaag: Mater. Sci. Eng. Vol. 313A (2001), p.145.

[8] N.H. van Dijk, L. Zhao, M. Th. Rekveldt, H. Fredrikze, O. Tegus, E. Brück, J. Sietsma, S. van der Zwaag: Physica B, Vol. 350 (2004), p. e463.


[9] S.G.E. te Velthuis, N.H. van Dijk, M. Th. Rekveldt, J. Sietsma and S. van der Zwaag: J. Appl. Phys. Vol. 89 (2001), p.1275.

[10] E.E. Underwood: Quantitative Stereology, (Addison-Wesley, Reading, 1970), p.27.

[11] K. Sugimoto, T. Iida, J. Sakaguchi and T. Kashima: ISIJ Inter. Vol. 40 (2000), p.902.