Microstructure Investigation of Thermally Induced Phase Transformation in Fe–Mn– Mo–Si Alloys

Öz

In this study, structural and crystallographic properties of phase transformations in Fe–Mn– Mo–Si (Mn = 15.14 wt.% and 18.45 wt.%) alloys were investigated. The effects of heat treatment temperature on microstructure were investigated by Scanning Electron Microscopy (SEM) and Metallurgical Microscopy (MM). In addition to this, crystallographic properties of phase transformations were revealed by using Transmission Electron Microscopy (TEM) and X–Ray Diffraction (XRD) methods. In the samples subjected to heat treatment at 750 C, it was observed that bainite structure was formed in the alloy where Mn amount was low and ferrite structure in the alloy where Mn amount was higher. In addition, it was found that both alloys heat–treated at 900 C had the same microstructure (pearlite structure) in SEM and MM microscopy. At the same time, microstructure observations revealed that bainite and pearlite structures contain a mixture of ferrite and cementite. In the TEM studies it was revealed by electron diffraction pattern analyses that bainite and ferrite phase crystallized in b.c.c. structure and cementite phase in orthorhombic structure. → type transformation was observed for –bainite formation, and orientation relationship was found as 〖(1 ̅11)〗_//〖(011)〗_ , 〖[101]〗_//〖[1 ̅11 ̅]〗_.

Anahtar Kelimeler

• Bainite
• Ferrite
• Cementite
• Pearlite
• Crystallographic properties
• TEM

Fe-Mn-Mo-Si Alaşımlarında Termal Etkili Faz Dönüşümlerinin Mikro Yapı İncelemeleri

Öz

Bu çalışmada, Fe-%XMn-Mo-Si (X=15,14 ve 18,45) alaşımlarında termal etki ile meydana gelen faz dönüşümlerinin yapısal ve kristalografik özellikleri incelenmiştir. Isıl işlem sıcaklığının mikro yapısı üzerine etkileri Taramalı Elektron Mikroskobu (SEM) ve Metalürji Mikroskobu (MM) incelemeleri ile yapıldı. Bunun yanı sıra kristalografik özellikleri ise Geçirmeli Elektron Mikroskobu (TEM) ve X-Işınları Kırınımı (XRD) yöntemleri kullanılarak ortaya çıkarılmıştır. 750 C’ de ısıl işleme tabi tutulan numunelerde Mn miktarının az olduğu alaşımda beynit yapı oluşurken Mn miktarının daha fazla olduğu alaşımda ferrit yapının oluştuğu gözlendi. Ek olarak, 900 C'de ısıl işlem görmüş her iki alaşımın da SEM ve MM mikroskopisinde aynı mikro yapıya (perlit yapı) sahip olduğu bulundu. Aynı zamanda, beynit ve perlit yapılarının ferrit ve sementit karışımını içerdiği mikro yapı gözlemleri ile ortaya konuldu. TEM incelemelerinde elektron kırınım deseni analizleri sayesinde beynit ve ferrit fazın b.c.c. yapısında, sementit fazın ise ortorombik yapıda kristalleştiği ortaya konuldu. -beynit oluşumu için  türü dönüşüm gözlendi ve dönme bağımlılığı 〖(1 ̅11)〗_//〖(011)〗_ , 〖[101]〗_//〖[1 ̅11 ̅]〗_ olarak bulundu.

Anahtar Kelimeler

• Beynit
• Ferrit
• Sementit
• Perlit
• Kristalografik özellikler
• TEM

Kaynakça

1. [1] Chowdhury, P., Canadinc, D., Sehitoglu, H. 2017. On deformation behavior of Fe-Mn based structural alloys. Materials Science and Engineering R Reports, 122, 1–28.
2. [2] Kirindi, T., Guler, E., Dikici, M. 2007. Effects of homogenization time on the both martensitic transformations and mechanical properties of Fe–Mn–Si–Cr–Ni shape memory alloy. Journal of Alloys and Compounds, 433, 202–206.
3. [3] Nishiyama, Z. 1978. Martensitic Transformations. 1nd edition. Academic Press. New York, 6s.
4. [4] Christian, J. W. 1975. The Theory of Transformation in Metals and Alloys. 2nd, the first part of that edition was revised and re-published. Pergamon Press. London, 813s.
5. [5] Wegst, C. W. 1986. Stahlschlüssel. 14nd edition. Verlag Stahlschlüssel Wegst Gmbh. Germany, 112s.
6. [6] Moffatt, W. G., Pearsall, G. W., Wulff, J. 1964. The structure and properties of materials, structure, part1. 1nd edition. John Wiley and Sons. New York, 134s.
7. [7] Brophy, J.H., Rose, R.M., Wulff J. 1964. The structure and properties of materials, thermodynamics, part2. 1nd edition. John Wiley and Sons. New York, 113s.
8. [8] Smith, W. F. 1986. Principles of Materials Science and Engineering. 1nd edition. McGraw-Hill. New York, 325s.

9. [9] Askeland, D. R., Webster, P. 1990. The Science and Engineering of Materials. 2nd edition. Chapman and Hall. London, 430s.
10. [10] Dieter, G., E. 1997. Effects of Composition, Processing, and Structure on Properties of Irons and Steels. Materials Selection and Design, Vol 20, ASM Handbook, ASM International, USA, 125s.
11. [11] Bain, E. C. 1932. Factors affecting the inherent hardenability of steel. Transactions of the American Society for Steel Treating, 20, 385-428.
12. [12] Bhadeshia, H. K. D. H., Christian, J. W. 1990. Bainite in stells. Metallurgical and Materials Transactions A, 21, 767–797.
13. [13] Irvine, K. J., Pickering, F. B. 1957. Low-carbon bainitic stells. Journal of the Iron and Steel Institute, 187, 292-309.
14. [14] Caballero, F. G., Bhadeshia, H. K. D. H., Mawella, K. J. A., Jones, D. G., Brown, P. 2002. Very Strong Low Temperature Bainite. Materials Science and Technology, 18, 279–284.
15. [15] Chang, L. C. 2004. Microstructures and reaction kinetics of bainite transformation in Si-rich stells. Materials Science and Engineering A, 368(1-2), 175-182.
16. [16] Srinivasan, G. R., Wayman, C. M. 1968. Transmission electron microscope study of the bainite transformation in iron-chromium-carbon alloys. Acta Metallurgica, 16(5), 609-620.
17. [17] Bhadeshia, H. K. D. H., Edmonds, D. V. 1980. The mechanism of bainite formation in steels. Acta Metallurgica, 28(9), 1265-1273.
18. [18] Greninger, A. B. Troianao, A. R. 1940. Crytallography of austenite decomposition. Trans. AIMME, 140, 307-336.
19. [19] Tsuzaki, K., Maki, T. 1995. Some Aspects of Bainite Transformation in Fe-Based Alloys. Journal de Physique, 5, 61-70.
20. [20] Klier, E. P. Lyman, T. 1944. The bainite reaction in hypoeutectoid steels. Trans. AIMME, 158, 394-422.
21. [21] Bhadeshia, H. K. D. H. 2001. Bainite in Steells. 2nd edition. The University Press. Cambridge, London, 63s.
22. [22] Zhang, M. X., Kelly, P. M. 2002. Accurate orientation relationship between ferrite and austenite in low carbon martensite and granular bainite. Scripta Materialia, 47, 749-755.
23. [23] Bhadeshia, H. K. D. H., Edmonds, D. V. 1979. The Bainite Transformation in a silicon steel. Metallurgical and Materials Transactions A, 10, 895–907.
24. [24] Lee, C. H., Bhadeshia, H. K. D. H., Lee, H. C. 2003. Effect of plastic deformation on the formation of acicular ferrite. Materials Science and Engineering A, 360, 249-257.
25. [25] Arici, G., Acarer, M., Uyaner, M. 2021. Effect of Co addition on microstructure and mechanical properties of new generation 3Cr-3W and 5Cr-3W steels. Engineering Science and Technology, an International Journal, 24(4), 974-989.
26. [26] Arici, G., Acarer, M., Uyaner, M. 2019. 3 ve 5 kromlu çeliklerde tantalyum ve krom ilavesinin mikroyapıya ve çentik darbe direncine etkisi. Selçuk-Teknik Dergisi, 18(3), 241-252.
27. [27] Tan, X., Xu, Y., Yang, X., Liu, Z., Wu, D. 2014. Effect of partitioning procedure on microstructure and mechanical properties of a hot-rolled directly quenched and partitioned steel. Materials Science and Engineering A, 594, 149–160.
28. [28] Tan, X., Xu, Y., Yang, X., Wu, D. 2014. Microstructure properties relationship in a onestep quenched and partitioned steel. Materials Science and Engineering A, 589, 101–111.
29. [29] Mijovilovich, A., Goncalves Vieira, A., Paniago, R., Pfannes, H. D., Mendonc Gonzalez, B. 2000. Mössbauer study of the retained austenitic phase in multiphase steels. Materials Science and Engineering A, 283, 65-69.
30. [30] Xing, X. L., Zhou, Y. F., Yang, Y. L., Gao, S. Y., Ren, X. J., Yang, Q. X. 2015. Surface modification of low-carbon nano-crystallite bainite via laser remelting and following isothermal transformation. Applied Surface Science, 353, 184–188.
31. [31] Batz, W., Mead, H. W., Birchenall, C. E. 1952. Diffusion of Silicon in Iron. Journal of Metals, 4(10), 1070.
32. [32] Weber, E. R. 1983. Transition metals in silicon. Applied Physics A, 30(1), 1–22.
33. [33] Maalekian, M. 2007. The effects of alloying elements on steels. https://online.tugraz.at/tug_online/voe_main2.getvolltext?pCurrPk=32837 (Erişim Tarihi: 18.02.2021).
34. [34] Aksoy, M., Kuzucu, V., Korkut, M. H. 1997. The influence of strong carbide-forming elements and homogenization on the wear resistance of ferritic stainless steel. Wear, 211, 265-270.
35. [35] Kuzucu, V., Aksoy, M., Korkut, M. H. 1998. The effect of strong carbide-forming elements such as Mo, Ti, V and Nb on the microstructure of ferritic stainless steel. Journal of Materials Processing Technology, 82, 165–171.
36. [36] Barford, J., Owen, W. S. 1962. The effect of austenite grain size and temperature on the rate of bainite transformation. Metal Science and Heat Treatment, 4, 359–360.
37. [37] Umemoto, M., Horiuchi, K., Tamura, I. 1982. Transformation Kinetics of Bainite during Isothermal Holding and Continuous Cooling. Tetsu-to-Hagane, 68, 461–470.
38. [38] Graham, L. W., Axon, H. J. 1959. The Effect of Austenitising Treatments on Formation of Lower Bainite in a Plain Carbon Steel. The Journal of the Iron and Steel Institute, 191, 361–365.
39. [39] Gao, G., Zhang, H., Tan, Z., Liu, W., Bai, B. 2013. A carbide-free bainite/martensite/austenite triplex steel with enhanced mechanical properties treated by a novel quenching–partitioning–tempering process. Materials Science and Engineering A, 559, 165–169.
40. [40] Kral, M. V. Spanos, G. 1999. Three-dimensional analysis of proeutectoid cementite precipitates. Acta Materialia, 47(2), 711-724.
41. [41] Kral, M. V., Spanos, G. 2003. Crystallography of grain boundary cementite dendrites. Acta Materialia, 51, 301–311.
42. [42] Mangan, M. A., Kral, M. V. Spanos, G. 1999. Correlation between the crystallography and morphology of proeutectoid widmanstatten cementite precipitates. Acta Materialia, 47(17), 4263-4274.
43. [43] Al-Abbasi, F. M. 2010. Micromechanical modeling of ferrite-pearlite steels. Materials Science and Engineering A, 527, 6904–6916.
44. [44] Wang, J., Van der Wolk, P., Van der Zwaag, S. 2000. On the influence of alloying elements on the bainite reaction in low alloy steels during continuous cooling. Journal of Materials Science, 35, 4393–4404. [45] Chen, H., Zhu, K., Zhao, L., Van der Zwaag, S. 2013. Analysis of transformation stasis during the isothermal bainitic ferrite formation in Fe–C–Mn and Fe–C–Mn–Si alloys. Acta Materialia, 61, 5458–5468.
45. [46] Chen, H., Borgenstam, A., Odqvist, J., Zuazo, Goune, M., Agren, J., Zwaag, S. 2013. Application of interrupted cooling experiments to study the mechanism of bainitic ferrite formation in steels. Acta Materialia, 61, 4512–4523.
46. [47] Palmer, T. A., Elmer, J. W., Babu, S. S. 2004. Observations of ferrite/austenite transformations in the heat affected zone of 2205 duplex stainless steel spot welds using time resolved X-ray diffraction. Materials Science and Engineering A, 374, 307–321.
47. [48] Yuan, F., Bian, X., Jiang, P., Yang, M., Wu, X. 2015. Dynamic shear response and evolution mechanisms of adiabatic shear band in an ultrafine-grained austenite-ferrite duplex steel. Mechanics of Materials, 89, 47–58.
48. [49] Colvın, F.H. 2007. The working of steel annealing, heat treating and hardening of carbon and alloy steel. 2nd Edition. Mcgraw-Hıll Book Company. New York, 22s.
49. [50] Goune, M., Danoix, F., Agren, J., Brechet, Y., Hutchinson, C.R., Militzer, M., Purdy, G., Van der Zwaag, S., Zurob, H. 2015. Overview of the current issues in austenite to ferrite transformation and the role of migrating interfaces therein for low alloyed steels. Materials Science and Engineering R Reports, 92, 1–38.
50. [51] Miyamoto, G., Karube, Y., Tadashi Furuhara, T. 2016. Formation of grain boundary ferrite in eutectoid and hypereutectoid pearlitic steels. Acta Materialia, 103, 370-381.
51. [52] Shimizu, K., Kawabe, N. 2001. Size dependence of delamination of high-carbon steel wire. ISIJ International, 41, 183-191.
52. [53] Oki, Y., Ibaraki, N., Ochiai, K., Minamida, T., Makii, K. 2000. Microstructure influence on ultra high tensile steel cord filament delamination. R&D Kobe Steel Engineering Reports, 50, 37-41.
53. [54] Larn, R. H., Yang, J. R. 2000. The effect of compressive deformation of austenite on the bainitic ferrite transformation in Fe-Mn-Si-C steels. Materials Science and Engineering A, 278, 278–291.
54. [55] Caballero, F. G., Miller, M. K., Garcia-Mateo, C., Cornide, J. 2013. New experimental evidence of the diffusionless transformation nature of bainite. Journal of Alloys and Compounds, 577, 626–630.
55. [56] Hulme-Smith, C. N., Lonardelli, I., Dippel, A. C., Bhadeshia, H.K.D.H. 2013. Experimental evidence for non-cubic bainitic ferrite. Scripta Materialia, 69, 409–412.
56. [57] Caballero, F. G., Miller, M. K., Garcia-Mateo, C., Capdevila, C., Babu, S. S. 2008. Redistribution of alloying elements during tempering of a nanocrystalline steel. Acta Materialia, 56, 188–199.
57. [58] Morito, S., Tanaka, H., Konishi, R., Furuhara, T., Maki T. 2003. The morphology and crystallography of lath martensite in Fe–C alloys. Acta Materialia, 51, 1789–1799.
58. [59] Kitahara, H., Ueji, R., Tsuji, N., Minamino, Y. 2006. Crystallographic features of lath martensite in low-carbon steel. Acta Materialia, 54, 1279–1288.
59. [60] Furuhara, T., Kawata, H., Morito, S., Miyamoto, G., Maki T. 2008. Variant selection in grain boundary nucleation of upper bainite. Metallurgical and Materials Transactions A, 39, 1003–1013.
60. [61] Lambert-Perlade, A., Gourgues, A. F., Pineau, A. 2004. Austenite to bainite transformation in the heat-affected zone of a high strength low alloy steel. Acta Materialia, 52, 2337–2348.
61. [62] Pereloma, E. V., Al-Harbi, F., Gazder, A. A. 2014. The crystallography of carbide-free bainites in thermo-mechanically processed low Si transformation-induced plasticity steels. Journal of Alloys and Compounds, 615, 96-110.
62. [63] Takayama, N., Miyamoto, G., Furuhara, T. 2012. Effects of transformation temperature on variant pairing of bainitic ferrite in low carbon steel. Acta Materialia, 60, 2387–2396.