Microstructure and corrosion behavior of the Ti-V-Cr-Nb high-entropy alloys in 3.5 wt% NaCl solution

Autor(es)

Yao, Jie-Yi ; Serrano, Leandro Bernardes ; Santos, Sydney Ferreira ; Cardoso, Katia Regina

• Tipo de documento: Artigo Científico
• Fonte: Corrosion Science; v. 218, p. 11-pg., 2023-04-11.

Resumo

Novel high-entropy alloys (HEAs) of the Ti(30-x)VCrNb(x) (x = 0, 5, 10, 15, and 20 at%) system were designed, synthesized, and characterized. The microstructural features were investigated by XRD, SEM, and EDS. The corrosion behavior was evaluated in 3.5 wt% sodium chloride (NaCl) solution of pH 5 at 25 degrees C by potentiody-namic polarization and electrochemical impedance spectroscopy (EIS). The investigated HEAs exhibited a single-phase BCC solid solution with dendritic microstructures. The polarization curves showed the Ti10V35Cr35Nb20 (Nb20) HEA exhibited the best corrosion resistance with the lowest corrosion current density (2.24 mu A/cm2) and corrosion rate (1.15 x 10-2 mm/yr). The interpretation of an equivalent electric circuit (EEC) suggested the formation of a stable passive oxide film on the HEAs, as indicated by good capacitive behavior and high impedance values (>104 omega cm2) at low frequencies and phase angles close to -80 degrees. This study demonstrated that an appropriate Nb content can stabilize the BCC phase and significantly enhance the corrosion resistance of the HEAs. (AU)

• Processo FAPESP: 19/22183-6 - Electrocatálise VI: aspectos fundamentais e aplicados em problemas emergentes e clássicos em conversão eletroquímica de energia
• Beneficiário: Edson Antonio Ticianelli
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 19/25302-6 - Ligas de alta entropia para armazenamento de hidrogênio
• Beneficiário: Kátia Regina Cardoso
• Modalidade de apoio: Auxílio à Pesquisa - Regular