Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 May 17;13(10):2309.
doi: 10.3390/ma13102309.

Hydrogen Permeation in X65 Steel under Cyclic Loading

Marina Cabrini  1   2 , Luigi Coppola  1   2   3 , Sergio Lorenzi  1   2   3 , Cristian Testa  1   2   3 , Francesco Carugo  1   2   3 , Diego Pesenti Bucella  1   2   3 , Tommaso Pastore  1   3
Affiliations

Hydrogen Permeation in X65 Steel under Cyclic Loading

Marina Cabrini et al. Materials (Basel). .

Abstract

This experimental work analyzes the hydrogen embrittlement mechanism in quenched and tempered low-alloyed steels. Experimental tests were performed to study hydrogen diffusion under applied cyclic loading. The permeation curves were fitted by considering literature models in order to evaluate the role of trapping-both reversible and irreversible-on the diffusion mechanism. Under loading conditions, a marked shift to the right of the permeation curves was noticed mainly at values exceeding the tensile yield stress. In the presence of a relevant plastic strain, the curve changes due to the presence of irreversible traps, which efficiently subtract diffusible atomic hydrogen. A significant reduction in the apparent diffusion coefficient and a considerable increase in the number of traps were noticed as the maximum load exceeded the yield strength. Cyclic loading at a tensile stress slightly higher than the yield strength of the material increases the hydrogen entrapment phenomena. The tensile stress causes a marked and instant reduction in the concentration of mobile hydrogen within the metal lattice from 55% of the yield strength, and it increases significantly in the plastic field.

Keywords: cathodic protection; elasto–plastic deformation; hydrogen permeation; low-alloyed steel.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Microstructure of X65 grade steel after metallographic etching (Nital 2%).
Figure 2
Figure 2
Specimens for the permeation tests: (1) In the absence of load; (2) Under cyclic loading.
Figure 3
Figure 3
Experimental permeation curves as adimensional flux/adimensional time (Φ = hydrogen flux; Φ∞ = steady state flux; t = permeation time; s = thickness): Comparison between the modeled permeation curve and the experimental data curve.
Figure 4
Figure 4
Relation between Dapp (apparent diffusivity) and applied stress.
Figure 5
Figure 5
Steady state anodic current (amplitude = ±20% tensile yield strength (TYS), frequency = 1 Hz) in function of an alternate component of loading.
Figure 6
Figure 6
Current variation as a function of load amplitude and frequency, and comparison between the cases of the presence and absence of diffusible atomic hydrogen.
Figure 7
Figure 7
Effect of instant variations of the maximum load (amplitude = ±10% TYS; frequency = 10−2 Hz) on the steady state anodic current (ia,∞).
Figure 8
Figure 8
Effect of instant variations of the maximum load (amplitude = ±10% TYS; frequency = 10−2 Hz) on the background passivity current (iP,∞).
Figure 9
Figure 9
Effect of instant variations of the maximum load (amplitude = ±10% TYS; frequency = 10−2 Hz) on the steady state hydrogen permeation current (iH,∞).
Figure 10
Figure 10
Response to subsequent variations of the maximum load (amplitude = ±10% TYS; frequency = 10−2 Hz) on the steady state anodic current (locally strain-hardened steel).
See this image and copyright information in PMC

References

    1. Eliassen S. New concept for cathodic protection of offshore pipelines to reduce hydrogen induced stress cracking (HISC) in high strength 13%Cr stainless steels. Corros. Eng. Sci. Technol. 2004;39:31–37. doi: 10.1179/147842204225016868. - DOI
    1. Orazem M.E., Esteban J.M., Kennelley K.J., Degerstedt R.M. Mathematical Models for Cathodic Protection of an Underground Pipeline with Coating Holidays: Part 1—Theoretical Development. Corrosion. 1997;53:264–272. doi: 10.5006/1.3280467. - DOI
    1. Kang D.H., Lee J.K., Kim T.W. Corrosion fatigue crack propagation of high-strength steel HSB800 in a seawater environment. Procedia Eng. 2011;10:1170–1175. doi: 10.1016/j.proeng.2011.04.195. - DOI
    1. Cheng A., Chen N.Z. An extended engineering critical assessment for corrosion fatigue of subsea pipeline steels. Eng. Fail. Anal. 2018;84:262–275. doi: 10.1016/j.engfailanal.2017.11.012. - DOI
    1. Knop M., Heath J., Sterjovski Z., Lynch S.P. Effects of cycle frequency on corrosion-fatigue crack growth in cathodically protected high-strength steels. Procedia Eng. 2010;2:1243–1252. doi: 10.1016/j.proeng.2010.03.135. - DOI

LinkOut - more resources