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Abnormal manifestation of the high-temperature degradation of the weld metal of a low-alloy steel welded joint

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Abstract

We have shown that hardness, impact toughness, mechanical properties in tension, and the local parameters of fracture mechanics (static and cyclic crack resistance) are sensitive to the operating degradation of weld metal of steam pipelines of thermal power plants made of 15Kh1M1F steel. The simultaneous decrease in the resistance to brittle and plastic fracture (hardness, strength, and impact toughness) represents a phenomenon of the operating degradation of weld metal. We have established a specific correlation between the characteristics of plasticity and other mechanical parameters of operated metal: the increase in °5 of operated weld metal is in good agreement with the decrease in its strength, whereas the reduction of Ψ correlates with the lowering of resistance to brittle fracture. Electrolytic hydrogenation decreases the characteristics of strength and plasticity of operated weld metal much stronger than in the initial state. The absence of ferritic edgings on the boundaries of primary austenitic grains makes for a low resistance to brittle fracture, and the change in acicular ferrite deteriorates the mechanical properties. The ductile fracture of nonoperated metal is replaced by brittle intercrystalline failure in operated metal.

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References

  1. O. M. Romaniv, H. M. Nykyforchyn, O. Z. Student, et al., “Effect of the operating damage of 12Kh1MF steam-pipeline steel on the characteristics of its crack resistance,” Fiz.-Khim. Mekh. Mater., 34, No. 1, 101–104 (1998).

    Google Scholar 

  2. H. M. Nykyforchyn and O. Z. Student, “Thermocycling in hydrogen environment as simulation method of pipeline steam steel’s damages,” in: M. W. Brown, E. R. de los Rios, and K. J. Miller (editors), Proc. 12th Biennial Conf. Fracture-ECF12 “Fracture from Defects” (Sheffield, 1998), Vol. III, EMAS, London (1998), pp. 1139–1144.

    Google Scholar 

  3. H. Nykyforchyn and O. Student, “Evaluation of the high-temperature hydrogen degradation of steels of power-generating and petrochemical equipment by the methods of fracture mechanics,” in: V. V. Panasyuk (editor), Fracture Mechanics of Materials and Strength of Structures [in Ukrainian], Karpenko Physicomechanical Institute, Ukrainian National Academy of Sciences, Lviv (2004), pp. 633–640.

    Google Scholar 

  4. V. V. Panasyuk, H. M. Nykyforchyn, O. Z. Student, and Z. V. Slobodyan, “Application of the approaches of fracture mechanics to the evaluation of hydrogen degradation of the steels of oil and steam pipelines,” in: O. E. Andreikiv, I. I. Luchko, and V. V. Bozhydarnyk (editors), Mechanics and Physics of the Fracture of Building Materials and Structures [in Ukrainian], Kamenyar, Lviv (2002), pp. 537–546.

    Google Scholar 

  5. O. Z. Student, “An accelerated method of hydrogen degradation of structural steels by thermocycling,” Fiz.-Khim. Mekh. Mater., 34, No. 4, 45–52 (1998).

    Google Scholar 

  6. O. Z. Student, W. Dudzinski, A. Kaminska, and H. M. Nykyforchyn, “Effect of high-temperature degradation of heat-resistant steel on mechanical and fractographic peculiarities of fatigue crack growth,” Fiz.-Khim. Mekh. Mater., 35, No. 4, 49–58 (1999).

    Google Scholar 

  7. H. M. Nykyforchyn, O. Z. Student, I. R. Dzioba, et al., “Degradation of the welded joints of steam pipelines of thermal power plants in a hydrogenating medium,” Fiz.-Khim. Mekh. Mater., 40, No. 6, 105–110 (2004).

    Google Scholar 

  8. O. Z. Student, A. D. Markov, and H. M. Nykyforchyn, “Specific features of the influence of hydrogen on the properties and mechanism of fracture of the metal of welded joints of steam pipelines at thermal power plants,” Fiz.-Khim. Mekh. Mater., 42, No. 4, 26–35 (2006).

    Google Scholar 

  9. SOU-N MPE 40.1.17.401:2004. Normative Document. Directions. Control of the Metal and Prolongation of the Service Life of the Main Elements of Boilers, Turbines, and Pipelines of Thermal Power Plants. Typical Instruction [in Ukrainian], Association of Power Enterprises “Branch Reserve-Investment Fund of the Development of Power Engineering,” Kyiv (2005).

  10. A. M. Makara, V. I. Lakomskii, and I. P. Zhovnitskii, “A study of hydrogen distribution in the welded joints of middle-alloy steels with austenitic and ferritic welds,” Avtom. Svarka, No. 11, 23–29 (1958).

  11. V. I. Makhnenko, T. V. Koroleva, and I. G. Lavrinets, “Effect of microstructural changes on the hydrogen redistribution in the fusion welding of structural steels,” Avtom. Svarka, No. 2, 7–13 (2002).

    Google Scholar 

  12. H. K. D. H. Bhadeshia and L.-E. Svensson, “Modelling the evolution of microstructure in steel weld metal,” in: H. Cerjak (editor), Mathematical Modelling of Weld Phenomena, Institute of Materials, London (1993), pp. 109–182.

    Google Scholar 

  13. S. S. Babu and H. K. D. H. Bhadeshia, “Transition from bainite to acicular ferrite in reheated Fe-Cr-C weld deposits,” Mater. Sci. Tech., 6, No. 10, 1005–1020 (1990).

    CAS  Google Scholar 

  14. K. Ichikawa and H. K. D. H. Bhadeshia, “Modelling of allotriomorphic ferrite in steel welds,” in: Mathematical Modelling of Weld Phenomena-3, Institute of Materials, London (1997), pp. 181–198.

    Google Scholar 

  15. P. A. Antikain, L. I. Ryabova, and A. V. Aksenov, “To the evaluation of serviceability of steam pipelines made of perlitic steels after long-term operation,” Probl. Prochn., No. 7, 35–42 (1971).

    Google Scholar 

  16. A. B. Vainman, R. K. Melekhov, and O. D. Smiyan, Hydrogen Embrittlement of Elements of High-Pressure Boilers [in Russian], Naukova Dumka, Kiev (1990).

    Google Scholar 

  17. O. Z. Student and H. V. Krechkovs’ka, “Evaluation of the technical state of the metal of steam pipelines with regard for the influence of stoppages in the operation of blocks of thermal power plants,” in: Problems of the Lifetime and Safety of Operation of Structures, Installations, and Machines [in Ukrainian], Institute of Electric Welding, Kyiv (2006), pp. 563–566.

    Google Scholar 

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Authors and Affiliations

  1. Karpenko Physicomechanical Institute, Ukrainian National Academy of Sciences, Lviv

    H. M. Nykyforchyn, O. Z. Student & A. D. Markov

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  1. H. M. Nykyforchyn
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  2. O. Z. Student
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  3. A. D. Markov
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Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 1, pp. 73–79, January–February, 2007.

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Nykyforchyn, H.M., Student, O.Z. & Markov, A.D. Abnormal manifestation of the high-temperature degradation of the weld metal of a low-alloy steel welded joint. Mater Sci 43, 77–84 (2007). https://doi.org/10.1007/s11003-007-0008-1

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  • DOI: https://doi.org/10.1007/s11003-007-0008-1

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