Y-doped AlCoCrFeNi2.1 eutectic high-entropy alloy with excellent oxidation resistance and structure stability at 1000°C and 1100°C

• Published in: Corrosion science 2021-03, Vol.180, p.109191, Article 109191
• Main Authors: Lu, Jie, Zhang, Han, Chen, Ying, Li, Ling, Liu, Xuanzhen, Xiao, Weiwei, Ni, Na, Zhao, Xiaofeng, Guo, Fangwei, Xiao, Ping
• Format: Article
• Language: English
• Subjects: Al2O3scale; Alloys; Aluminum oxide; Doping; Eutectic alloys; Eutectics; High entropy alloys; High temperature; High-entropy alloy; Lamellar structure; Oxidation; Oxidation resistance; Structural stability
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2020.109191

•The Y-doped AlCoCrFeNi2.1 EHEA exhibits superior oxidation resistance and structural stability at high temperatures.•Doping of Y into the Y into the AlCoCrFeNi2.1 EHEA can significantly improve Al2O3 scale adhesion.•The Al-rich β phase with a high aspect ratio is beneficial to facilitate the exclusive formation of Al2O3 scale during oxidation at 1000 °C.•The eutectic lamellar structure composed of γ’ and β phases is highly stable after prolonged oxidation at 1000 °C and 1100 °C. In this study, the oxidation behavior of AlCoCrFeNi2.1 eutectic high entropy alloy (EHEA) with/without Y doping at 1000 °C and 1100 °C was reported. The doping of minor Y is crucial to improving the Al2O3 scale adhesion and achieving its durability at high temperatures. The oxidation rates of Y-doped AlCoCrFeNi2.1 EHEA at 1000 °C and 1100 °C are comparable and even lower compared with conventional Al2O3-forming NiCoCrAlY/CoNiCrAlY alloys. The superior oxidation resistance and highly stable eutectic lamellar structure after high-temperature oxidation make Y-doped AlCoCrFeNi2.1 EHEA show a tremendous potential in high-temperature application.