Abstract
In-situ electrochemical (EC)-AFM is employed to investigate the localized corrosion of the AlxCoCrFeNi high-entropy alloys (HEAs). Surface topography changes on the micro/sub-micro scale are monitored at different applied anodizing potentials in a 3.5 wt% NaCl solution. The microstructural evolutions with the increased Al content in the alloys are characterized by SEM, TEM, EDS and EBSD. The results show that by increasing the Al content, the microstructure changes from single solid-solution to multi-phases, leading to the segregations of elements. Due to the microstructural variations in the AlxCoCrFeNi HEAs, localized corrosion processes in different ways after the breakdown of the passive film, which changes from pitting to phase boundary corrosion. The XPS results indicate that an increased Al content in the alloys/phases corresponds to a decreased corrosion resistance of the surface passive film.
| Original language | English |
|---|---|
| Pages (from-to) | 533-544 |
| Number of pages | 12 |
| Journal | Applied Surface Science |
| Volume | 439 |
| DOIs | |
| State | Published - May 1 2018 |
Funding
In-situ EC-AFM and XPS measurements were carried out at the Center for Nanophase Materials Sciences (CNMS), Oak Ridge National Laboratory, supported by the U.S. Department of Energy, Basic Energy Sciences, Scientific User Facilities Division. The authors appreciate Dr. Arthur Baddorf from CNMS for his kind help on the XPS tests. The authors would like to appreciate the financial support from the U.S. Department of Energy, Office of Fossil Energy, National Energy Technology Laboratory ( DE-FE-0008855 , DE-FE-0024054 , and DE-FE-0011194 ), National Science Foundation ( DMR-1611180 ), the “863” Program of China under Nos. 2008AA031702 and 2012AA03A507 , and Beijing Municipal Natural Science Foundation under No. 2162026 . Y.S. is grateful to the China Scholarship Council for the financial support during her visit to The University of Tennessee. P.K.L. is pleased to acknowledge the financial support by the Ministry of Science and Technology of Taiwan under No. MOST 105-2221-E-007-017-MY3 , the National Tsing Hua University, Taiwan , and the Dalian University of Technology, China . In-situ EC-AFM and XPS measurements were carried out at the Center for Nanophase Materials Sciences (CNMS), Oak Ridge National Laboratory, supported by the U.S. Department of Energy, Basic Energy Sciences, Scientific User Facilities Division. The authors appreciate Dr. Arthur Baddorf from CNMS for his kind help on the XPS tests. The authors would like to appreciate the financial support from the U.S. Department of Energy, Office of Fossil Energy, National Energy Technology Laboratory (DE-FE-0008855, DE-FE-0024054, and DE-FE-0011194), National Science Foundation (DMR-1611180), the “863” Program of China under Nos. 2008AA031702 and 2012AA03A507, and Beijing Municipal Natural Science Foundation under No. 2162026. Y.S. is grateful to the China Scholarship Council for the financial support during her visit to The University of Tennessee. P.K.L. is pleased to acknowledge the financial support by the Ministry of Science and Technology of Taiwan under No. MOST 105-2221-E-007-017-MY3, the National Tsing Hua University, Taiwan, and the Dalian University of Technology, China.
| Funders | Funder number |
|---|---|
| 863 Program of China | 2008AA031702, 2012AA03A507 |
| National Science Foundation | DMR-1611180 |
| U.S. Department of Energy | |
| Office of Fossil Energy | |
| Basic Energy Sciences | |
| Oak Ridge National Laboratory | |
| University of Tennessee | |
| National Energy Technology Laboratory | DE-FE-0024054, DE-FE-0011194, DE-FE-0008855 |
| China Scholarship Council | |
| Ministry of Science and Technology, Taiwan | MOST 105-2221-E-007-017-MY3 |
| Beijing Municipal Natural Science Foundation | 2162026 |
Keywords
- AFM
- High-entropy alloy
- Localized corrosion
- Microstructure
- Passive film