Effects of grain size and deformation temperature on hydrogen-enhanced vacancy formation in Ni alloys
書誌事項
- 公開日
- 2017-04
- 権利情報
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- https://www.elsevier.com/tdm/userlicense/1.0/
- https://www.elsevier.com/legal/tdmrep-license
- http://www.elsevier.com/open-access/userlicense/1.0/
- DOI
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- 10.1016/j.actamat.2017.02.016
- 公開者
- Elsevier BV
この論文をさがす
説明
Abstract Positron annihilation spectroscopy and thermal desorption spectroscopy experiments were combined to ascertain the role of hydrogen on generation of vacancies and vacancy clusters in Ni alloys. The effects of grain size and deformation temperature are emphasized for pure Ni single crystals and polycrystalline Ni-201 alloy samples with two grain sizes that were thermally pre-charged with 3000 appm hydrogen. Variation in positron lifetime and intensity suggests that hydrogen enhances and stabilizes vacancies and vacancy clusters. Additionally, grain boundaries and the regions adjacent to them are preferential sites for vacancy and cluster formation. Hydrogen-altered vacancies and vacancy clusters are manifest in yield behavior differences: uniform vacancy distributions augment strength increases after hydrogen charging; enhanced yield strength during cryogenic deformation is ascribed to an ‘Orowan type’ strengthening mechanism while cross-slip restriction dominates hardening behavior at room temperature.
収録刊行物
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- Acta Materialia
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Acta Materialia 128 218-226, 2017-04
Elsevier BV