Abstract
The variations in the pop-in behavior of an equiatomic CoCrFeMnNi high-entropy alloy under different hydrogen charging/discharging conditions were characterized via in-situ electrochemical nanoindentation. Results show that hydrogen accumulatively reduces both pop-in load and width, among which the reduction of pop-in width is more noticeable than that of pop-in load. Moreover, the hydrogen reduction effect on both pop-in load and width is reversible when hydrogen is degassed during anodic discharging process. Particularly, the hydrogen-reduced pop-in width was studied in detail by a comprehensive energy balance model. It is quantitatively shown that the dissolved hydrogen enhances lattice friction, leading to an increased resistance to dislocation motion. As a result, fewer dislocations can be generated with a higher hydrogen concentration, causing a smaller pop-in width. This is the first time that the pop-in width indicated dislocation mobility under hydrogen impact is quantitively revealed.
Original language | English |
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Pages (from-to) | 118-122 |
Number of pages | 5 |
Journal | Journal of Materials Science and Technology |
Volume | 98 |
DOIs | |
Publication status | Published - 30 Jan 2022 |
Externally published | Yes |
Keywords
- Dislocation
- High-entropy alloy
- Hydrogen
- Nanoindentation
- Pop-in