Abstract
The present work investigates the homogenization effect of 1250 °C heat treatment on the AlxCoCrFeNi high-entropy alloys (HEAs). The multi-phase microstructures with chemical segregations are inevitable with the increased Al content in the alloys, which cause work function variations and localized corrosion. After heat treatment, the homogenization effect revealed by the microstructure simplification and chemical-segregation reduction leads to the decreased work function variations and the improved corrosion resistance. Thermodynamic calculations that are reliable to predict the phase transformations of the AlxCoCrFeNi HEAs, indicates a further enhancement in corrosion resistance through annealing could be guided for many other HEAs systems.
Original language | English |
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Pages (from-to) | 120-131 |
Number of pages | 12 |
Journal | Corrosion Science |
Volume | 133 |
DOIs | |
State | Published - Apr 1 2018 |
Funding
The authors are grateful to Dr. Zhi Tang from the Alloy Technology Division, Alcoa Technical Center, who has provided the forged Al x CoCrFeNi alloys, and are thankful to Prof. William Y. Wang from The Pennsylvania State University for providing valuable guidance in the work-function analysis. SKPFM measurements were carried out at the Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, supported by the U.S. Department of Energy, Basic Energy Sciences, Scientific User Facilities Division. 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 ), and the support from the “863” Program of China under Nos. 2008AA031702 and 2012AA03A507. Y.S. is grateful to the China Scholarship Council for the financial support during her visit to The University of Tennessee .
Keywords
- A. Alloys
- B. AFM
- C. Pitting corrosion
- C. Segregation