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 boundari...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2020-12-01
|
| Series: | Materials |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1944/13/24/5785 |
| _version_ | 1797544261177049088 |
|---|---|
| author | Abril Azócar Guzmán Jeongwook Jeon Alexander Hartmaier Rebecca Janisch |
| author_facet | Abril Azócar Guzmán Jeongwook Jeon Alexander Hartmaier Rebecca Janisch |
| author_sort | Abril Azócar Guzmán |
| collection | DOAJ |
| description | 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 α-Fe single crystal (001) and (111) cleavage planes, as well as on the Σ5(310)[001] and Σ3(112)[1<inline-formula><math display="inline"><semantics><mover accent="true"><mn>1</mn><mo>¯</mo></mover></semantics></math></inline-formula>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 <i>ab initio</i> 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. |
| first_indexed | 2024-03-10T13:58:08Z |
| format | Article |
| id | doaj.art-69ee2a49c0944e10882a610ad8a75031 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-10T13:58:08Z |
| publishDate | 2020-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-69ee2a49c0944e10882a610ad8a750312023-11-21T01:26:08ZengMDPI AGMaterials1996-19442020-12-011324578510.3390/ma13245785Hydrogen Embrittlement at Cleavage Planes and Grain Boundaries in Bcc Iron—Revisiting the First-Principles Cohesive Zone ModelAbril Azócar Guzmán0Jeongwook Jeon1Alexander Hartmaier2Rebecca Janisch3Interdisciplinary Centre for Advanced Materials Simulation (ICAMS), Ruhr-Universität Bochum, 44801 Bochum, GermanyInterdisciplinary Centre for Advanced Materials Simulation (ICAMS), Ruhr-Universität Bochum, 44801 Bochum, GermanyInterdisciplinary Centre for Advanced Materials Simulation (ICAMS), Ruhr-Universität Bochum, 44801 Bochum, GermanyInterdisciplinary Centre for Advanced Materials Simulation (ICAMS), Ruhr-Universität Bochum, 44801 Bochum, GermanyHydrogen 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 α-Fe single crystal (001) and (111) cleavage planes, as well as on the Σ5(310)[001] and Σ3(112)[1<inline-formula><math display="inline"><semantics><mover accent="true"><mn>1</mn><mo>¯</mo></mover></semantics></math></inline-formula>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 <i>ab initio</i> 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.https://www.mdpi.com/1996-1944/13/24/5785density functional theoryhydrogen embrittlementhydrogen enhanced decohesiongrain boundary segregation |
| spellingShingle | Abril Azócar Guzmán Jeongwook Jeon Alexander Hartmaier Rebecca Janisch Hydrogen Embrittlement at Cleavage Planes and Grain Boundaries in Bcc Iron—Revisiting the First-Principles Cohesive Zone Model Materials density functional theory hydrogen embrittlement hydrogen enhanced decohesion grain boundary segregation |
| title | Hydrogen Embrittlement at Cleavage Planes and Grain Boundaries in Bcc Iron—Revisiting the First-Principles Cohesive Zone Model |
| title_full | Hydrogen Embrittlement at Cleavage Planes and Grain Boundaries in Bcc Iron—Revisiting the First-Principles Cohesive Zone Model |
| title_fullStr | Hydrogen Embrittlement at Cleavage Planes and Grain Boundaries in Bcc Iron—Revisiting the First-Principles Cohesive Zone Model |
| title_full_unstemmed | Hydrogen Embrittlement at Cleavage Planes and Grain Boundaries in Bcc Iron—Revisiting the First-Principles Cohesive Zone Model |
| title_short | Hydrogen Embrittlement at Cleavage Planes and Grain Boundaries in Bcc Iron—Revisiting the First-Principles Cohesive Zone Model |
| title_sort | hydrogen embrittlement at cleavage planes and grain boundaries in bcc iron revisiting the first principles cohesive zone model |
| topic | density functional theory hydrogen embrittlement hydrogen enhanced decohesion grain boundary segregation |
| url | https://www.mdpi.com/1996-1944/13/24/5785 |
| work_keys_str_mv | AT abrilazocarguzman hydrogenembrittlementatcleavageplanesandgrainboundariesinbccironrevisitingthefirstprinciplescohesivezonemodel AT jeongwookjeon hydrogenembrittlementatcleavageplanesandgrainboundariesinbccironrevisitingthefirstprinciplescohesivezonemodel AT alexanderhartmaier hydrogenembrittlementatcleavageplanesandgrainboundariesinbccironrevisitingthefirstprinciplescohesivezonemodel AT rebeccajanisch hydrogenembrittlementatcleavageplanesandgrainboundariesinbccironrevisitingthefirstprinciplescohesivezonemodel |