Mechanism of Hydrogen Embrittlement of Austenitic Steels


Article Preview

Three main hypotheses of hydrogen embrittlement (HE) of austenitic steels are discussed based on the studies of the interatomic interactions, hydrogen-induced phase transformations and dislocations properties. Measurements of electron spin resonance and ab initio calculations of the electron structure witness that the concentration of conduction electrons increases due to hydrogen, which enhances the metallic character of interatomic bonds. The hypothesis of brittle hydrogen-induced phases is disproved by the studies of the silicon-alloyed steels: the silicon-caused increase in the fraction of the εH martensite is accompanied by the decrease of HE. Studies of strain-dependent internal friction have shown the hydrogen-caused decrease in the start stress of microplasticity and increase in the velocity of dislocations in accordance with HELP hypothesis. A mechanism of HELP is proposed based on the hydrogencaused enhancement of the metallic character of interatomic bonds, which results in the local decrease of the shear modulus within the hydrogen atmospheres round the dislocations. As consequence, the line tension of the dislocations followed by the hydrogen atoms decreases, which finds its expression in the early start of dislocation sources, decreased distance between dislocations in the pile-ups and increased velocity of dislocations. A mechanism of localization of plastic deformation is proposed based on the observations of the hydrogen-enhanced concentration of equilibrium vacancies.



Materials Science Forum (Volumes 539-543)

Main Theme:

Edited by:

T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran




V. Shivanyuk et al., "Mechanism of Hydrogen Embrittlement of Austenitic Steels", Materials Science Forum, Vols. 539-543, pp. 4249-4254, 2007

Online since:

March 2007




[1] Quick, N.R., Johnson, H.H.: Metall. Trans. Vol. 10A (1979), p.67.

[2] Brass, A.M., Chanfreau, A., Chene, J., In: Thompson, A.W., Moody, N.R., (eds), Hydrogen Effects on Material Behaviour, TMS Publ., Warrendale, Pennsylvania, 1990, p.19.

[3] Hirth, J.P.: Metall Trans. Vol. 11A (1980), p.861.

[4] Inoue, A., Hosoya, Y., Masumoto, T.: Trans. ISIJ Vol. 19 (1979), p.170.

[5] Narita, N., Altstetter, C.J., Birnbaum, H.K.: Metall. Trans. Vol. 13A (1982), p.1355.

[6] Beachem, C.D.: Metall. Trans. Vol. 3 (1972), p.437.

[7] Lynch, S.P.: Acta metall. Vol. 36 (1988), p.2639.

[8] Birnbaum, H.K., Sofronis, P.: Mater. Sci. & Eng. Vol. A176 (1994), p.191.

[9] P. Blaha, K. Schwarz, G.K.H. Madsen, D. Kvasnicka and J. Luitz: WIEN2k, An Augmented Plane Wave + Local Orbitals Program for Calculating Crystal Properties (Karlheinz Schwarz, Techn. Universität Wien, Austria), 2001. ISBN 3-9501031-1-2.

[10] V. N. Shivanyuk, B. D. Shanina, A. V. Tarasenko, V. G. Gavriljuk and J. Foct : Scripta Materialia Vol. 44 (2001), p.2765.


[11] Szumer, A., Janko, A.: Corrosion Vol 35 (1979), p.461.

[12] V. N. Shivanyuk, J. Foct and V. G. Gavriljuk: Scripta Materialia Vol. 49 (2003), p.601.

[13] Schramm, R.E., and Reed, R.P.: Metall. Trans. Vol. 16A (1975), p.1345.

[14] Bogachev, I.N., Egolaev V.F.: Iron-Manganese alloys (in Russian) Metallurgy, Moskow, (1964).

[15] Макогон, Ю.Н., Николин, Б.И., Соколов, O.Г., Известия АН СССР, Metaллы, 1978, 3, 120.

[16] Uhlig, U.U., White, R.U.: Trans. ASM Vol. 53 (1960), p.157.

[17] Turnbull, A., Hutchings, R.B.: Mater. Sci. & Eng. Vol. A 177 (1994), p.161.

[18] Brass, A.M., Collet-Lacoste, J., In: Turnbull, A., (ed. ), Hydrogen Transport & Cracking in Metals, Publ. the Institute of Materials, London, 1995, p.142.

[19] V. N. Shivanyuk, J. Foct and V. G. Gavriljuk: Materials Science and Engineering Vol. A300 (2001), p.284.

[20] Asano, S., and Otsuka, R.: Scripta metall. Vol. 10 (1976), p.1015.

[21] Ferreira, P.J., Robertson, I.M., Birnbaum, H.K.: Acta mater. Vol. 46 (1998), p.1749.

[22] Lecoester, F., Chêne, J., Noel, D.: Mater. Sci. & Eng. Vol. A 262 (1999), p.173.

[23] Bobyr, A.M., Bugaev, V.N., Smirnov, A.A.: Reports of Academy of Sci. of USSR Vol. 320 (1991), p.1113.

[24] Fukai, Y., Okuma, N.: Japan J. Appl. Phys. Vol. 32 (1993), p. L1256.

[25] V.G. Gavriljuk, V.N. Bugaev, Yu.N. Petrov, A.V. Tarasenko, B.Z. Yanchitsky: Scripta Mater. Vol. 34 (1996), p.903.