Performance assessments of porous FeCoNiCrAlx high-entropy alloys in high-temperature oxidation, carbonization and sulfidation atmospheres

• Published in: Journal of alloys and compounds Vol. 930; p. 167437
• Main Authors: Zhang, Huibin, Guo, Fei, Wan, Leilei, Gao, Zhencheng, Chen, Taotao, Cao, Huazhen, Chen, Hongyu, Zheng, Guoqu
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 05.01.2023; Elsevier BV
• Subjects: Carbonization; Corrosion resistance; FeCoNiCrAl; Flue gas; Heat resistant alloys; High entropy alloys; High temperature; High-entropy alloy; Iron; Mechanical properties; Oxidation; Phase composition; Porosity; Porous material; Porous materials; Recarburizing; Structural stability; Sulfidation; Synthesis; FeCoNiCrAl; Oxidation; Sulfidation; Porous material; High-entropy alloy
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2022.167437

Porous FeCoNiCrAlx high-entropy alloys (HEAs) with different atomic fraction of Al were developed as potential candidates for high-temperature filter materials by reactive synthesis using blended elemental Fe/Co/Ni/Cr/Al powders. This method combines the creation of porous structure with the direct synthesis of HEAs, and takes the advantage of the role of Al in enhancing the porosity of porous materials. The effects of Al atomic fraction on the pore structure parameters, phase compositions, microstructures and mechanical strengths of porous FeCoNiCrAlx were investigated, and a comprehensive assessment of the high-temperature corrosion resistances of these materials was carried out. The results showed that the increase of Al atomic fraction not only improved the porosity and intrinsic mechanical performance of porous FeCoNiCrAlx, but also provided enhanced protection against high-temperature corrosions such as oxidation, carbonization and sulfidation. The optimal atomic fraction range of Al in porous FeCoNiCrAlx HEAs was 0.6–1.0, which could make this material keep structural and chemical stability in potential high-temperature flue gas environment. [Display omitted] •Porous FeCoNiCrAlx high-entropy alloys were prepared by reactive synthesis.•The role of Al atomic fraction on the performances of porous FeCoNiCrAlx was studied.•Increasing the Al content enhances the oxidation resistance of porous FeCoNiCrAlx.•The preoxidized porous FeCoNiCrAlx can effectively resist high-temperature carbonization.•Porous FeCoNiCrAlx with high Al content are resistant to high-temperature sulfidation.