Microstructural aspects upon hydrogen environment embrittlement of various bcc steels

Michler, Thorsten; Naumann, Jörg

doi:10.1016/j.ijhydene.2009.10.092

Cited by 171 publications

(31 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have focused this work on Fe-based systems due to the increasing importance of ferritic steels and their hydrogen-enhanced degradation modes in gas pipeline [8,9] and next generation reactor applications [10,11]. Iron crystallises in a body-centred cubic (bcc) structure, namely ferrite phase, at temperatures below 912…”

Section: Introductionmentioning

confidence: 99%

Surface atomic relaxation and magnetism on hydrogen-adsorbed Fe(110) surfaces from first principles

Chohan

Jimenez-Melero

Koehler

2016

Applied Surface Science

View full text Add to dashboard Cite

We have computed adsorption energies, vibrational frequencies, surface relaxation and buckling for hydrogen adsorbed on a body-centred-cubic Fe(110) surface as a function of the degree of H coverage. This adsorption system is important in a variety of technological processes such as the hydrogen embrittlement in ferritic steels, which motivated this work, and the Haber-Bosch process. We employed spin-polarised density functional theory to optimise geometries of a six-layer Fe slab, followed by frozen mode finite displacement phonon calculations to compute Fe-H vibrational frequencies. We have found that the quasi-threefold (3f) site is the most stable adsorption site, with adsorption energies of ∼3.0 eV/H for all coverages studied. The long-bridge (lb) site, which is close in energy to the 3f site, is actually a transition state leading to the stable 3f site. The calculated harmonic vibrational frequencies collectively span from 730 to 1220 cm −1 , for a range of coverages. The increased first-to-second layer spacing in the presence of adsorbed hydrogen, and the pronounced buckling observed in the Fe surface layer, may facilitate the diffusion of hydrogen atoms into the bulk, and therefore impact the early stages of hydrogen embrittlement in steels.

show abstract

Section: Introductionmentioning

confidence: 99%

Surface atomic relaxation and magnetism on hydrogen-adsorbed Fe(110) surfaces from first principles

Chohan

Jimenez-Melero

Koehler

2016

Applied Surface Science

View full text Add to dashboard Cite

show abstract

“…In hydrogen the distribution of deformations for different bases of measurement is insignificant. During visual observation it was revealed, that in hydrogen the zone of plastically deformed material is smaller, that can be explained only by localization of plastic deformation due to hydrogen influence rather than by increasing in yield stress σ 0.2 because this parameter of such structural steels increases slightly (Michler and Naumann 2010;Robertson 2001;Tsyrulnyk et al 2007).…”

Section: Results and Their Analysismentioning

confidence: 99%

Hydrogen influence on fracture of sheet carbon steel

et al. 2012

View full text Add to dashboard Cite

Results of the researches of hydrogen influence on fracture of 65 sheet spring steel by several methods are presented. The distribution of deformation and topography of a hollow in front of the crack tip is determined, the stress intensity factor is calculated, fractographic analysis of a fracture surface and metallographic analysis of the morphology of crack distribution are carried out. The decrease of operation characteristics of the material as a result of hydrogen influence which becomes apparent in localization of plastic deformations and intensive delamination on the layers of rolling is established.

show abstract

“…Actually, C 0 is dominantly dependent on the density of reversible H traps, N T , on the assumption that the irreversible traps could be saturated by the H atoms [38]. According to previous works [39,40,41,42], H traps such as solute atoms, GBs and dislocations were generally regarded as reversible traps, due to their bonding energy being lower than 60 kJ/mol. Among these reversible traps, the solute atoms were assumed to decrease with increasing T t , due to increased precipitation, as shown in Figure 9 and Figure 10.…”

Section: Discussionmentioning

confidence: 99%

Sulfide Stress Cracking Behavior of a Martensitic Steel Controlled by Tempering Temperature

Sun

Wang

et al. 2018

Materials

View full text Add to dashboard Cite

A medium-carbon Cr–Mo–V martensitic steel was thermally processed by quenching (Q) at 890 °C and tempering (T) at increasing temperatures from 650 °C to 720 °C and the effect of tempering temperature, Tt, on sulfide stress cracking (SSC) behaviors was estimated mainly via double cantilever beam (DCB) and electrochemical hydrogen permeation (EHP) tests and microstructure characterization. The results indicate that the threshold stress intensity factor for SSC, KISSC, increased with increasing Tt. The overall and local H concentration around the inclusions decreased with increasing Tt, due to reductions in the amounts of solute atoms, grain boundaries and dislocations, which effectively prevented SSC initiation. Also, increasing Tt caused an increased fraction of high-angle boundaries, which evidently lowered the SSC propagation rate by more frequently diverting the propagating direction and accordingly restricted SSC propagation. The overall SSC resistance of this Q&T–treated steel was therefore significantly enhanced.

show abstract

Microstructural aspects upon hydrogen environment embrittlement of various bcc steels

Cited by 171 publications

References 32 publications

Surface atomic relaxation and magnetism on hydrogen-adsorbed Fe(110) surfaces from first principles

Surface atomic relaxation and magnetism on hydrogen-adsorbed Fe(110) surfaces from first principles

Hydrogen influence on fracture of sheet carbon steel

Sulfide Stress Cracking Behavior of a Martensitic Steel Controlled by Tempering Temperature

Contact Info

Product

Resources

About