Jiaqin Xu¹, Shuhei Shinzato¹, Shihao Zhang¹, Fan-Shun Meng¹, Shigenobu Ogata^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.31, No.1, pp. 1-2, 2024, DOI:10.32604/icces.2024.011814

Abstract Hydrogen has the potential to be the clean energy solution to achieve the sustainable development goals (SDGs). However, from preparation to utilization, the hydrogen embrittlement can not be neglected. Hydrogen embrittlement occurs as a result of hydrogen affecting dislocations motion and cracks opening. Dislocation motion in hydrogen environment has not been clarified although several mechanisms have been proposed, including the hydrogen enhanced decohesion (HEDE), the hydrogen enhanced macroscopic ductility (HEMP), the hydrogen enhanced local plastic model (HELP), etc. It is essential to comprehend the underlying hydrogen-dislocation interactions that cause embrittlement. Also, dynamics of dislocation motion… More >

Tadashi Kasuya^1,*, A. Toshimitsu Yokobori Jr², Nobuyuki Ishikawa³, Manabu Enoki¹, Satoshi Minamoto⁴

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.2, pp. 120-120, 2019, DOI:10.32604/icces.2019.05227

Abstract Weld cold cracking is categorized as hydrogen cracking. To assess cold cracking susceptibility of steel HAZ (heat affected zone), it is necessary to estimate local hydrogen content and residual stress at a weld root that are in general numerically calculated by FEM and/or FDM. To conduct numerical calculations, physical and mechanical properties such as diffusion coefficient of hydrogen in steel are necessary. In this work, we have developed empirical formulae to calculate HAZ hardness, hydrogen diffusion coefficient and tensile properties. The present empirical formula of HAZ hardness is expressed using chemical compositions of a welded… More >

A.Toshimitsu Yokobori Jr^1,*, Go. Ozeki¹, Toshihito OHMI^1,2, Tadashi Kasuya³, Nobuyuki Ishikawa⁴, Manabu Enoki³, Satoshi Minamoto⁵

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.2, pp. 119-119, 2019, DOI:10.32604/icces.2019.05177

Abstract Authors have been founded that hydrogen diffusion and concentration behavior for notched specimens of multi-materials with space distribution of various material properties were dominated not only by the space gradient of hydrostatic stress caused by the notch tip, ∇σ_p but also by that of diffusion coefficient, ∇D(T, HV, ε_p) caused by space distributions of temperature, hardness and plastic strain due to multi-materials. In this research, on the basis of our proposed coupled analysis of heat transfer induced thermal stress driven hydrogen diffusion, the effect of ∇D(T, HV, ε_p) ) on hydrogen concentration behavior was clarified by solving the… More >

San-Qiang Shi

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 35-36, 2011, DOI:10.3970/icces.2011.020.035

Abstract Zirconium and its alloys are key structural materials used in the nuclear power industry. In service, these metals are susceptible to a slow corrosion process that leads to a gradual pickup of hydrogen impurities from the environment. It is well known that hydrogen impurity will be attracted to stress concentrators such as notch and crack tips. At a certain hydrogen level, a complicated pattern of hydride precipitates can develop around these stress concentrators. Because of the brittleness of these hydrides, the original strength of the alloys can be reduced by orders of magnitude, and the… More >