resumo
Ni-Cr-Mo is a candidate to substitute Co binders in WC-based composites, where high corrosion resistance is required. This work focused on the effect of Cr on the corrosion susceptibility of WC-Ni-Cr-Mo composites, in acid media. Specimens were produced by powder metallurgy followed by microstructural, chemical and mechanical characterization. Open circuit potential measurements, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were employed to evaluate the corrosion susceptibility of WC-Ni-Cr-Mo alloys with different Cr content. The results highlight the greater aggressiveness of chloride medium compared to sulphate environment, and reveal that Cr can effectively decrease corrosion susceptibility without hampering the mechanical properties in both media, especially in chloride solution, where major improvements are observed.
palavras-chave
STAINLESS-STEELS; ANION TYPE; CO; BEHAVIOR; NICKEL; HARDMETALS; TOUGHNESS; CHLORIDE; SURFACE; FILMS
categoria
Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering
autores
Santos, RF; Rocha, AMF; Bastos, AC; Cardoso, JP; Rodrigues, F; Fernandes, CM; Sacramento, J; Ferreira, MGS; Senos, AMR; Fonseca, C; Vieira, MF; Malheiros, LF
nossos autores
Grupos
G2 - Materiais Fotónicos, Eletrónicos e Magnéticos
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
Projectos
HARDCorr - Desenvolvimento de metal duro com elevada resistência ao desgaste e à corrosão (HardCorr)
agradecimentos
This research work was financed by Portugal 2020 through European Regional Development Fund (FEDER) in the frame of Operational Competitiveness and Internationalization Programme (POCI) and the scope of the project HARDCorr (POCI-01-0247-FEDER-003382). This work was also developed within the scope of the project CICECO-Aveiro Institute of Materials, FCT Ref. UID/CTM/50011/2019, financed by national funds through the FCT/MCTES.