Abstract
The main evolution stages of the phase diagram of Fe–C in the carbide region (on the right from the cementite line) is a recently discussed theoretical topic that has been considered. It has been determined that previously isolated ε-Fe2C, χ-Fe5C2, and g-Fe7C3 carbides (except for cementite Θ-Fe3C) are nonstoichiometric compounds. Thus, they are variable composition phases containing stoichiometric composition or second-type interstitial solid solutions based on daltonides and berthollides. It has been stated that the iron–cementite phase diagram can be identified as the iron–ε-Fe2C carbide phase diagram in the concentration range of 0–9.7% C. The following phase transformations are introduced to the diagram: reaction of nonvariant syntectic equilibrium of cementite Θ-Fe3C crystallization; reaction of peritectic equilibrium of carbide χ-Fe5C2 crystallization; low-temperature peritectoid transformation of carbide, at which solid solutions of ferrite and cementite form solid solution possessing broad homogeneity range based on ε-carbide Fe2C berthollide. It has been shown that the carbide phases represent a uniform isomorphous quasi-carbide solid solution, while the carbide phase crystallizes in the form of the carbide phase mixture as quasi-eutectics.
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Notes
Iron monoxide characterized by lattice defects of bcc lattice, which is described by Fe1–xO formula. It represents nonstoichiometric compound with deficiency of iron atoms.).
Mineralogical name of cementite.
REFERENCES
Tyrkiel, E., Wykres Żelazo-Węgiel w Rozwoju Historycznym, Warsaw: Zakład Narod. im. Ossolińskich, 1963.
Sil’man, G.I., Sistema zhelezo-uglerod (Iron-Carbon System), Bryansk: Bryansk. Gos. Inzh.-Tekhnol. Akad., 2007.
Zhukov, A.A., Geomtericheskaya termodinamika splavov zheleza (Geometric Thermodynamics of Iron Alloys), Moscow: Metallurgiya, 1979, 2nd ed.
Bannykh, O.A., Budberg, P.B., Alisova, S.P., et al., Diagrammy sostoyaniya dvoinykh i mnogokomponentnykh sistem na osnove zheleza (Phase Diagrams of Iron-Containing Binary and Multicomponent Systems), Moscow: Metallurgiya, 1986.
Gulyaev, A.P., On the iron-carbon diagram, Met. Sci. Heat Treat., 1990, vol. 32, no. 7, pp. 493–494.
Jang, J.H., Kim, I.G., and Bhadeshia, H.K.D., ε-Carbide in alloy steels: first-principles assessment, Scr. Mater., 2010, vol. 63, pp. 121–123.
Hiroyuki, O., The C–Fe (carbon-iron) system, J. Phase Equilib., 1992, vol. 13, no. 5, pp. 543–565.
Zhukov, A.A., Phase diagram of alloys of the system Fe–C, Met. Sci. Heat Treat., 1988, vol. 30, no. 1, pp. 249–255.
Sil’man, G.I., Refinement of the Fe–C diagram on the basis of results of a thermodynamic analysis and generalization of data for Fe–C and Fe–C–Cr systems, Met. Sci. Heat Treat., 1997, vol. 39, no. 11, pp. 451–456.
Zhukov, A.A., Snezhnoi, R.L., Shterenberg, L.E., et al., Iron-diamond system state diagram, Dokl. Akad. Nauk SSSR, 1973, vol. 211, no. 1, pp. 145–147.
Kosolapova, T.Ya., Karbidy (Carbides), Moscow: Metallurgiya, 1968.
Zhukov, A.A., Shterenberg, L.E., Shalashov, V.A., et al., Pseudohexagonal iron carbide Fe7C3 and eutectic Fe3C–Fe7C3 in the Fe–C system, Izv. Akad. Nauk SSSR, Met., 1973, no. 1, pp. 181–184.
Zhukov, A.A. and Snezhnoi, R.L., The shape of the liquidus curve in the melting region of cementite on the iron-diamond state diagram, Izv. Akad. Nauk SSSR, Met., 1976, no. 3, pp. 192–199.
Kulikov, I.S., Termodinamika karbidov i nitridov: spravohnoe izdanie (Thermodynamics of Carbides and Nitrides: Handbook), Chelyabinsk: Metallurgiya, 1988.
Vysokotemperaturnye karbidy (High-Temperature Carbides), Samsonov, G.V., Ed., Kiev: Naukova Dumka, 1975.
Gavriulik, V.G. and Theisesn, W., Low-temperature martensitic transformation in tool steels in relation to their deep cryogenic treatment, Acta Mater., 2013, vol. 61, pp. 1705–1715.
Kundu, S. and Bhadeshia, H. K.D.H., Crystallographic texture and intervening transformations, Scr. Mater., 2007, vol. 57, pp. 869–872.
Toth, L.E., Transition Metal Carbides and Nitrides, Amsterdam: Elsevier, 1971.
Vysokotemperaturnye karbidy (High-Temperature Carbides), Samsonov, G.V., Ed., Kiev: Naukova Dumka, 1975.
Samsonov, G.V., Kosolapova, T.Ya., Gnesin, G.G., et al., Karbidy i splavy na ikh osnove (Carbides and Alloys Based on Them), Kiev: Naukova Dumka, 1976.
Wicks, C.E. and Block, F.E., Thermodynamic Properties of 65 Elements: Their Oxides, Halides, Carbides and Nitrides, Washington: US Gov. Printing Off., 1963.
Bhadeshia, H.K.D.H., Cementite, Int. Mater. Rev., 2020, vol. 65, no. 1, pp. 1–27.
Litasov, K.D., Popov, Z.I., Gavryushkin, P.N., et al., First-principles calculations of the equations of state and relative stability of iron carbides at the Earth’s core pressures, Russ. Geol. Geophys., 2015, vol. 56, nos. 1–2, pp. 164–171.
Bataleva, Yu.V., Palyanov, Yu.N., Borzdov, Yu.M., et al., Conditions for diamond and graphite formation from iron carbide at the P–T parameters of lithospheric mantle, Russ. Geol. Geophys., 2016, vol. 57, no. 1, pp. 176–189.
Lomaeva, S.F., Mechanisms of the formation of the structure, phase composition, and properties of iron-based nanosystems during mechanical activation and organic media, Extended Abstract of Doctoral (Phys.-Math.) Dissertation, Izhevsk: Inst. Phys. Technol., Ural. Otd., Ross. Akad. Nauk, 2007.
Barinov, V.A., Tsurin, V.A., Kazantsev, V.A., and Surikov, V.T., Carbonization of α-Fe upon mechanical alloying, Phys. Met. Metallogr., 2014, vol. 115, no. 1, pp. 53–68.
Barinov, V.A., Kazantsev, V.A., and Surikov, V.T., Temperature investigations of mechanosynthesized cementite, Phys. Met. Metallogr., 2014, vol. 115, no. 6, pp. 576–585.
Barinov, V.A., Protasov, A.V., and Surikov, V.T., Studying mechanosynthesized Hägg carbide (χ‑Fe5C2), Phys. Met. Metallogr., 2015, vol. 116, no. 8, pp. 791–801.
Barinov, V.A., Tsurin, V.A., and Surikov, V.T., Study of mechanically synthesized carbide Fe7C3, Phys. Met. Metallogr., 2010, vol. 110, no. 5, pp. 474–484.
Voronin, V.I., Berger, I.F., Gornostyrev, Yu.N., et al., Composition of cementite in the dependence on the temperature. In situ neutron diffraction study and ab initio calculations, JETP Lett., 2010, vol. 91, no. 3, pp. 143–146.
Tsementit v uglerodistykh stalyakh: kollektivnaya monografiya (Cementite in Carbon Steels: Collective Monograph), Schastlivtsev, V.M., Ed., Yekaterinburg: Uzh.-Metod. Tsentr, UPI, 2017.
Noskov, F.M., Kveglis, L.I., and Leskov, M.B., Strukturoobrazovanie v zone kontakta metallov pri sovmestnoi plasticheskoi deformatsii (Structuring in the Contact Area of Metals during Combined Plastic Deformation), Krasnoyarsk: Sib. Fed. Univ., 2019.
Volkov, V.A., Ul’yanov, A.I., Chulkina, A.A., and El’kin, I.A., Phase formation mechanisms in the mechanosynthesis of Fe–C alloys, Khim. Fiz. Mezoskop., 2018, vol. 20, no. 4, pp. 502–507.
Zalkin, V.M. and Kraposhin, V.S., Structure of iron-carbon melts. About stability of cementite in melts, Met. Sci. Heat Treat., 2010, vol. 52, no. 1, pp. 3–6.
Zalkin, V.M., On the theory of eutectic alloys and presentation of the theory in textbooks on physical metallurgy, Met. Sci. Heat Treat., 2009, vol. 51, no. 3, pp. 153–159.
Gulyaev, A.P., On the iron-carbon diagram, Met. Sci. Heat Treat., 1990, vol. 32, no. 7, pp. 493–494.
Davydov, S.V., Low-temperature carbide transformation in pearlite of medium-carbon steels, Steel Transl., 2020, vol. 50, no. 9, pp. 639–647.
Okishev, K.Yu. and Mirzaev, D.A., Possibile redistribution of carbon atoms in the cementite lattice, Vestn. Yuzh.-Ural Gos. Univ., Ser. Metall., 2011, vol. 17, no. 36, pp. 56–60.
Okishev, K.Yu. and Mirzaev, D.A., Pores in the crystal lattice of cementite and the position of carbon atoms, Vestn. Yuzh.-Ural Gos. Univ., Ser. Matem., Fiz., Khim., 2003, vol. 3, no. 6, pp. 79–85.
Schastlivtsev, V.M., Yakovleva, I.L., Mirzaev, D.A., and Okishev, K.Yu., On the possible positions of carbon atoms in the cementite lattice, Phys. Met. Metallogr., 2003, vol. 96, no. 3, pp. 313–320.
Medvedeva, N.I., Kar’kina, L.E., and Ivanovskii, A.L., Effects of atomic disordering and nonstoichiometry in the carbon sublattice on the energy-band structure of cementite, Phys. Met. Metallogr., 2003, vol. 96, no. 5, pp. 452–456.
Lord, O.T., Walter, M.J., Dasgupta, R., et al., Melting in the Fe–C system to 70 GPa, Earth Planet. Sci. Lett., 2009, vol. 284, pp. 157–167.
Nakajima, Y., Takahashi, E., Suzuki, T., and Funakoshi, K., “Carbon in the core” revisited, Phys. Earth Planet. Inter., 2009, vol. 174, pp. 202–211.
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Translated by A. Muravev
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Davydov, S.V. Phase Equilibria in the Carbide Region of Iron–Carbon Phase Diagram. Steel Transl. 50, 888–896 (2020). https://doi.org/10.3103/S0967091220120025
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DOI: https://doi.org/10.3103/S0967091220120025