Hydrogen embrittlement at cleavage planes and grain boundaries in bcc iron-revisiting the first-principles cohesive zone model
- Hydrogen embrittlement, which severely affects structural materials such as steel, comprises several mechanisms at the atomic level. One of them is hydrogen enhanced decohesion (HEDE), the phenomenon of H accumulation between cleavage planes, where it reduces the interplanar cohesion. Grain boundaries are expected to play a significant role for HEDE, since they act as trapping sites for hydrogen. To elucidate this mechanism, we present the results of first-principles studies of the H effect on the cohesive strength of \(\alpha\)-Fe single crystal (001) and (111) cleavage planes, as well as on the \(\Sigma\)5(310)[001] and \(\Sigma\)3(112)[1\(\bar {1}\)0] symmetrical tilt grain boundaries. The calculated results show that, within the studied range of concentrations, the single crystal cleavage planes are much more sensitive to a change in H concentration than the grain boundaries. Since there are two main types of procedures to perform \(\textit {ab initio}\) tensile tests, different in whether or not to allow the relaxation of atomic positions, which can affect the quantitative and qualitative results, these methods are revisited to determine their effect on the predicted cohesive strength of segregated interfaces.
Author: | Abril Azócar GuzmánORCiDGND, Jeongwook JeonGND, Alexander HartmaierORCiDGND, Rebecca JanischORCiDGND |
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URN: | urn:nbn:de:hbz:294-79185 |
DOI: | https://doi.org/10.3390/ma13245785 |
Parent Title (English): | Materials |
Publisher: | MDPI |
Place of publication: | Lausanne |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2021/03/01 |
Date of first Publication: | 2020/12/18 |
Publishing Institution: | Ruhr-Universität Bochum, Universitätsbibliothek |
Tag: | Open Access Fonds density functional theory; grain boundary segregation; hydrogen embrittlement; hydrogen enhanced decohesion |
Volume: | 13 |
Issue: | 24 |
First Page: | 5785-1 |
Last Page: | 5785-16 |
Note: | Article Processing Charge funded by the Deutsche Forschungsgemeinschaft (DFG) and the Open Access Publication Fund of Ruhr-Universität Bochum. |
Institutes/Facilities: | Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) |
Dewey Decimal Classification: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften, Maschinenbau |
Licence (English): | Creative Commons - CC BY 4.0 - Attribution 4.0 International |