| Full text | |
| Author(s): |
Zemanate, Ana Maria
;
Jorge Junior, Alberto Moreira
;
Andreani, Gisele Ferreira de Lima
;
Roche, Virginie
;
Cardoso, Ratia Regina
Total Authors: 5
|
| Document type: | Journal article |
| Source: | Electrochimica Acta; v. 441, p. 13-pg., 2023-01-13. |
| Abstract | |
In this study, the effects of three different nickel concentrations on the microstructure, hardness, and corrosion properties of AlCrFeCoNix (x = 1.0, 1.5, 2.0) high entropy alloys (HEA) were investigated. The alloys were obtained by arc melting from high-purity raw materials and subjected to heat treatment at 1125 degrees C for 5 h. Microstructural characterization revealed a dendritic morphology for the equimolar and AlCrFeCoNi1.5 alloys, while the AlCrFeCoNi2 alloy presented a hypoeutectic microstructure. Differences in microstructure and chemical composition were observed between the dendritic and interdendritic regions, with clear segregation of Cr in the interdendritic areas. The increase in Ni content and the heat treatment resulted in the formation of the FCC phase, consequently reducing the alloys' hardness. The corrosion properties of HEA were evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy methods in a 3.5% NaCl solution. The results show high resistance to localized corrosion of the alloys, evidenced by the low values of corrosion current densities, and high pitting potentials. The protective film's formation depends on Ni content, which is also related to FCC/BCC ratio and phase compositions. The heat treatment generally results in a more homo-geneous, thicker, and less defective oxide film. (AU) | |
| FAPESP's process: | 21/06546-1 - Design and production of high entropy refractory alloy for implants' application: mechanical properties, surface modification, bioactivity, and corrosion behavior |
| Grantee: | Alberto Moreira Jorge Junior |
| Support Opportunities: | Scholarships abroad - Research |
| FAPESP's process: | 19/25302-6 - High entropy alloys for hydrogen storage |
| Grantee: | Kátia Regina Cardoso |
| Support Opportunities: | Regular Research Grants |