| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
Additive Manufacturing: Materials Design and Alloy Development III -- Super Materials and Extreme Environments
|
| Presentation Title |
Understanding the Corrosion Mechanism of an Equimolar AlCoCrFeNi High-entropy Alloy Additively Manufactured by Electron Beam Melting |
| Author(s) |
Kenta Yamanaka, Hiroshi Shiratori, Manami Mori, Kazuyo Omura, Tadashi Fujieda, Kosuke Kuwabara, Akihiko Chiba |
| On-Site Speaker (Planned) |
Kenta Yamanaka |
| Abstract Scope |
In this study, the corrosion behaviour and passive film characteristics of an equimolar AlCoCrFeNi HEA additively manufactured by electron beam melting (EBM) were investigated. The as-built specimen consisted of the BCC/B2 matrix and grain-boundary FCC phase, although the phase fraction varied along the build direction. Consequently, the EBM specimen shows better corrosion performance than a cast counterpart in terms of both corrosion and passivation current density, while the top part of EBM specimen does not represent an apparent passivity during anodic polarization in a 3.5 wt.% NaCl solution. The electrochemical impedance spectroscopy captured an enhanced charge transfer resistance and the formation of more protective passive film of the bottom part. The enrichment of Cr in the B2 phase during the post-melt high-temperature exposure in the EBM process was responsible for the improved stability of the passive film, suppressing the selective dissolution of the B2 phase in the bottom part. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Additive Manufacturing, High-Entropy Alloys, Environmental Effects |