Imperial College London
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DrEmilioMartinez-Paneda

Faculty of Engineering, Department of Civil and Environmental Engineering

Visiting Reader
 
 
 
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Contact

 

+44 (0)20 7594 8188e.martinez-paneda Website

 
 
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Location

 

249Skempton BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Díaz:2020:10.1007/s10704-019-00411-8,
author = {Díaz, A and Cuesta, II and Martinez-Paneda, E and Alegre, JM},
doi = {10.1007/s10704-019-00411-8},
journal = {International Journal of Fracture},
pages = {17--35},
title = {Analysis of hydrogen permeation tests considering two different  modelling approaches for grain boundary trapping in iron},
url = {http://dx.doi.org/10.1007/s10704-019-00411-8},
volume = {223},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The electrochemical permeation test is one of the most used methods forcharacterising hydrogen diffusion in metals. The flux of hydrogen atomsregistered in the oxidation cell might be fitted to obtain apparentdiffusivities. The magnitude of this coefficient has a decisive influence onthe kinetics of fracture or fatigue phenomena assisted by hydrogen and dependslargely on hydrogen retention in microstructural traps. In order to improve thenumerical fitting of diffusion coefficients, a permeation test has beenreproduced using FEM simulations considering two approaches: a continuum 1Dmodel in which the trap density, binding energy and the input latticeconcentrations are critical variables and a polycrystalline model wheretrapping at grain boundaries is simulated explicitly including a segregationfactor and a diffusion coefficient different from that of the interior of thegrain. Results show that the continuum model captures trapping delay, but itshould be modified to model the trapping influence on the steady state flux.Permeation behaviour might be classified according to different regimesdepending on deviation from Fickian diffusion. Polycrystalline syntheticpermeation shows a strong influence of segregation on output flux magnitude.This approach is able to simulate also the short-circuit diffusion phenomenon.The comparison between different grain sizes and grain boundary thicknesses bymeans of the fitted apparent diffusivity shows the relationships between theregistered flux and the characteristic parameters of traps.
AU  - Díaz,A
AU  - Cuesta,II
AU  - Martinez-Paneda,E
AU  - Alegre,JM
DO  - 10.1007/s10704-019-00411-8
EP  - 35
PY  - 2020///
SN  - 0376-9429
SP  - 17
TI  - Analysis of hydrogen permeation tests considering two different  modelling approaches for grain boundary trapping in iron
T2  - International Journal of Fracture
UR  - http://dx.doi.org/10.1007/s10704-019-00411-8
UR  - http://arxiv.org/abs/1912.02525v1
UR  - https://link.springer.com/article/10.1007%2Fs10704-019-00411-8
UR  - http://hdl.handle.net/10044/1/75653
VL  - 223
ER  -
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