Novel Procedure for Production of Duplex Martensitic-Ferritic Plain Low Carbon Steels

Document Type : Original Articles

Authors

• mehdi shaban ghazani ¹
• hossein shokrvash ²

¹ sahand university of technology

² maragheh university

10.22067/ma.v0i29.43678

Abstract

In the present study, plain low carbon steel with 0.033 wt.% carbon content was subjected to severe pressure during continuous cooling from austenite region. The pressure was increased gradually and then suddenly released. As a result, a microstructure composed of 80% lath martensite and 20% ferrite was produced. Results showed that the martensite formation is not only a function of the cooling rate but also the hydrostatic pressure which effects the austenite to ferrite transformation start temperature (Ar3).

Keywords

• Plain Low Carbon steel
• Duplex Microstructure
• martensite
• Cooling Under pressure

---

References

1. Azghandi S.H., Ahmadabadi V.G., Raoofian I., Fazeli F., Zare M., Zabett A., Reihani H., "Investigation on decomposition behavior of austenite under continuous cooling in vanadium microalloyed steel", Materials and design, Vol. 88, pp. 751-758, (2015).

2. Digges T., "Influence of austenitic grain size on the critical cooling rate of high-purity iron-carbon alloys", Journal of Research of the National Bureau of Standards, Vol. 2, pp. 723-742, (1940).

3. Capdevila C., Caballero F.G., Anders C.G., "Austenite Grain Size Effects on Isothermal Allotriomorphic Ferrite Formation in 0.37C-1.45Mn-0.11V Microalloyed Steel", Materials Transactions, Vol. 44, pp. 1087-1095, (2003).

4. Carpenter K.R., Killmore C.R., "The Effect of Nb on the Continuous Cooling Transformation Curves of Ultra-Thin Strip CASTRIP© Steels", Metals, Vol. 5, pp. 1857-1877, (2015).

5. Bodnar R.L., Hansen S.S., "Effects of austenite grain size and cooling rate on Widmanstätten ferrite formation in low-alloy steels", Metallurgical and Materials Transactions A, Vol. 25, pp. 665-675, (1994).

6. Wilson E.A.,"Theoretical calculations of kinetics of equiaxed ferrite transformations in Fe, Fe–Ni, and Fe–Cr alloys", Materials Science and Technology, Vol. 7, Issue 12, pp. 1089-1100, (1991).

7. Wilson E.A., "The γ→α Transformation in Low Carbon Irons", ISIJ International, Vol. 34, pp. 615-630, (1994).

8. Mirzayev D.A., Schastlivtsev V.M., "The Influence of the Cooling Rate on the Kinetics of the Polymorphous Transformations in Metals", ICOMAT 86, Japan Institute of Metals, Sendai, pp.

282-290, (1986).

9. Merkel S., Wenk H.R., Gillet P., Mao H.K., Hemley R.J., "Deformation of polycrystalline iron up to 30GPa and 1000K", Physics of the Earth and Planetary Interiors, Vol. 145, pp. 239-251, (2004).

10. Kakeshita T., Saburi T., Shimizu K., "Effects of hydrostatic pressure and magnetic field on martensitic transformations", Materials Science and Engineering A, Vol. 273-275, pp. 21-39, (1999).

11. Zhang J., Guyot F., "Thermal equation of state of iron and Fe0.91Si0.09", Physics and Chemistry of Minerals, Vol. 26, pp. 206-211, (1999).

12. Tonkov E.Y., Ponyatovsky E.G., "Phase transformations of elements under high pressure", CRC Press, (2005).

13. Rakhshkhorshid M., Seyed H.H., Monajatzadeh H., "The use of hot torsion testing for determination of critical temperatures of API X65 steel", Modares Mechanical Engineering, Vol. 14, pp. 291-29, (2015).

14. Alberto Moriera J.J., Henrique L., Balancin O., "Ultra Grain Refinement During the Simulated Thermomechanical-processing of Low Carbon Steel", Journal of Materials Research and Technology, Vol. 1, pp. 141-147, (2012).

15. Gautam J., Miroux A., Moerman J., Barbatti C., Liempt P.V., Kestenes A., "Determination of the nonrecrystallisation temperature (Tnr) of austenite in high strength C–Mn steels", Materials Science Forum, Vol. 706-709, pp. 2722-2727, (2012).

16. Chen P.C., Winchell P.G., "Martensite lattice changes during tempering", Metallurgical Transactions A, Vol. 11, pp. 1333-1339, (1980).

17. Michal G.M., Ernst F., Kahn H., Cao Y., Oba F., Agarwal N., Heuer A.H., "Carbon supersaturation due to paraequilibrium carburization: Stainless steels with greatly improved mechanical properties", Acta Materialia, Vol. 54, pp. 1597- 1066, (2006).

18. Chen P.C., Hall B.O., Winchell P.G., "Atomic displacements due to C in Fe Ni C martensite", Metallurgical Transactions A, Vol. 11, pp. 1323- 1331, (1980).

19. Raghavan V., Cohen M., "Measurement and interpretation of isothermal martensitic kinetics", Metallurgical Transactions A, Vol. 2, pp. 2409- 2418, (1971).

20. Bohemen S.M.C., Sietsma J., "Effect of composition on kinetics of athermal martensite formation in plain carbon steels", Materials Science and Technology, Vol. 25, pp. 1009-1012, (2009).