ccct nicrmov · ccct diagrams were also compared with those of the cct diagrams and the cause was...

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    Drawing CCCT Diagrams and Investigation of Deformation Effects on Martensite and Bainite Trabsformations in NiCrMoV Steel

    R. Taherian, A. Najafi Zadeh, M. Shamanian, R. Shateri Department of Materials Engineering, Isfahan University of Technology

    Isfahan Alloy steel complex

    Abstract: In this study, two CCCT diagrams are drawn to be compared with a CCT diagram. The CCCT diagrams represent continuous cooling transformations in stress assisted state. The increased Md and Bd temperatures of CCCT diagrams were also compared with those of the CCT diagrams and the cause was investigated from both thermodynamic and metallurgical viewpoints. Thermodynamic examinations revealed that stress causes the mechanical driving force to increase but the total free energy of transformation to decrease; hence, Md and Bd will rise. Metallurgical investigations showed that if deformation temperatures are selected in a manner to increase the structural strength of the original austenite grains prior to deformation, the shear force required for martensite and bainite transformations will arduously obtain; hence, Md and Bd will fall. However, if recrystallization or full recovery occurs during or after deformation, interior grain structure softens and the shear force required for martensite and bainite transformations will readily obtain; hence, Md and Bd will rise. It was also found that the nose in CCCT curves are shifted to the left as compared to that of CCT curves. This indicates that deformation of steel enhances bainite formation more readily than that of the martensite phase.

    Keywords: CCCT, CCT, Hot deformation, Martensite, Bainite.

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    Steels”, Material Science and Engineering A, pp. 1-11, 2003.

    13. Tamura. I., Chiaki. O., Tomo. T., Hiroshi. S., “Thermomechanical Processing of High Strength Low Alloy Steels”, Butterworth &Co, British Library Cataloguing in Publication data, 1988.

    14. Ming-Chun, Z., Ke, Y., Fu-Ren., Yi-Yin, S., “Continuous Cooling Transformation of Undeformed and Deformed Low Carbon Pipeline Steels”, Material Science and Engineering A, pp. 1-11, 2003.

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    16. Bhadeshia, H. K. D. H., “ Bainite in Steels”, Institute of Materials, London,1992.

    17. Fang, H. S., Yang, J. B., Yang, Z. G., Bai, B. Z., “The Mechanism of Bainite Transformation in Steels”, Scripta Materialia, 42, pp. 157-162 , 2003.

    18. Murr, L. E., Staudhammer, K. P., Hecker, S. S., “Effects of Strain State and Strain Rate on Deformation-induced Transformation in 304 Stainless Steel: Part2: Microstructural Study”, Metallurgical Transaction A, Vol. 13A, pp. 627-635, 1982.

    19. Luo, H., Zhao, Lie, Kruijver, S., Sietma, J., Zwaag, S. V. D., “Effect of Intercritical Deformation on Bainite Formation in Al-containing TRIP Steel” ISIJ International, Vol. 43, No. 8, pp. 1219-1227, 2003.

    20. Pope, L. E., “The Effect of Plastic Deformation on the Martensite-to-Austenite Transition in an Iron-Nickel Alloy”, Metallurgical Transactions, Vol. 3, pp. 2151-2156, 1972.

    21. Nichol, T. J., Judd, G., Ansell, G. S., “The Relationship Between Austenite Strength and the Transformation to Martensite in Fe-10 pct Ni-0.6 pct C Alloys”, Metallurgical Transactions A, Vol. 8A, 1877-1883, 1977.

    22. Olson, G. B., Cohen, M.,”Kinetics of Strain-induced Martensitic Nucleation”, Metallurgical Transactions A, Vol. 6A, pp. 791-795, 1975.

    23. Koyima, A., Watanabe, Y., Terada,Y., Yoshie, A., Tamehiro, H., “Ferrite Grain refinement by Large Reduction per Pass in Nonrecrystallization Temperature Region of Austenite”, ISIJ International, No. 5, pp. 603-610, 1996.

    24. Breedis, J. F., “Influence of Dislocation Substructure on the Martensitic Transformation in Stainless Steel”, Acta Metallurgica, Vol. 13, pp. 239-250, 1965.

    25. Forter, L. F., Rosenthal, P. C., “Effect of Applied Tensile Stress on Phase Transformations in Steel”, Acta Metallurgica, Vol. 7, 504514, 1959.

    26. Suezawa, M., Cook, H. E., “On the Nucleation Martensite”, Acta Matallurgica, Vol. 28, pp. 443-432, 1980.

    27. Staudhammer, K. P., Murr, L. E., Hecker, S. S., “Nucleation and Evolution of Strain- induced

    Martensitic (B.C.C.) Embryos and Substructure in Stainless Steel: A Transmission Electron Microscope Study”, Acta Metallurgica, Vol. 31, No. 2, pp. 267-274, 1983.

    28. Suzuki, T., Kojima, H., Suzuki, K., Hashimoto, T., Ichihara, M., “An Experimental Study of the Martensite Nucleation and Growth in 18/8 Stainless Steel”, Acta Metallurgica, Vol. 25, pp. 1151-1162, 1977.

    29. Singh, S. B., Bhadeshia, H. K. D. H., “Strain Induced Stabilization of Austenite against Bainite Transformation”, Indian Institute of Technology, Karagpur, India, 1996.

    30. Okaguchi, S., Ohtani, H., Ohmori, Y., “Morphology of Widmanstatten and Bainitic Ferrites”, Materials Transactions, JIM, Vol. 32, No. 8., pp. 697-704, 1991.

    31. Tsuzaki, K., Fujiwara, K., Maki, T., “Bainite Reaction in Fe-Ni-C Alloys”, Materials Transaction, JIM, Vol. 32., No. 8, pp. 667-678, 1991.

    32. Lawrynowicz, Z., Barbacki, A., “Features of Bainite Transformation in Steels”, Advances in Materials Science, Vol. 2, No. 1 (2), 2002.

    33. Ohmori, Y., “Bainite Transformations in Extremely Low Carbon Steels”, ISIJ International, Vol. 35, No. 8, pp. 962-968, 1995.

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