resumo
Highly corrosive agents, such as saltwater, hydrogen sulphide, hydrofluoric or hydrochloric acids, are frequently found in oil and gas exploration. The high costs associated with the premature replacement of equipment damaged by corrosion and the consequent production losses justify the search for more resistant materials. In this work, the corrosion behaviour of cemented carbides with different Ni-based binders in highly corrosive envi-ronments (HCl and HF) was studied by electrochemical techniques (EIS, OCP and polarization curves). HF was slightly more aggressive than HCl and far more corrosive than near neutral NaCl solution. The hardmetals with Ni-based binders presented a corrosion resistance superior to WC-Co in all environments.
palavras-chave
ELECTROCHEMICAL-BEHAVIOR; CEMENTED CARBIDES; WC; PASSIVITY
categoria
Materials Science; Metallurgy & Metallurgical Engineering
autores
Pereiraa, P; Rocha, AMF; Sacramento, J; Oliveira, FJ; Malheiros, LF; Senos, AMR; Bastos, AC
nossos autores
Ana Maria de Oliveira e Rocha Senos
Colaborador
António Alexandre Cunha Bastos
Investigador Auxiliar
Filipe José Alves de Oliveira
Investigador PrincipalGrupos
G2 - Materiais Fotónicos, Eletrónicos e Magnéticos
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
Projectos
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
agradecimentos
Acknowledgements P. Pereira acknowledges FCT for financial support (SFRH/BD/138040/2018) . This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MEC (PIDDAC) . Furthermore, we acknowledge HARDTECH-POCI-01-0247-FEDER-045283, financed by FEDER under the PT2020 Partnership Agreement. A. M. Ferro Rocha thanks FCT for the PhD grant SFRH/BD/147060/2019. A. C. Bastos is funded by national funds (OE) , through FCT-Funda?a?o para a Cie?ncia e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. Finally, the authors gratefully acknowledge Dr. Rui Rocha from CEMUP for his assistance during some of the SEM observations.