Evaluation of the anticorrosive behavior of epoxy-Nb 2 O 5 paint in high temperatures submitted to the environment with
- PDF / 2,452,591 Bytes
- 12 Pages / 595.276 x 790.866 pts Page_size
- 81 Downloads / 141 Views
Evaluation of the anticorrosive behavior of epoxy-Nb2O5 paint in high temperatures submitted to the environment with sulfuric acid Maria Eduarda Dias Serenario, Bernardo Augusto Farah Santos, Luiz Roberto Martins de Miranda, Alysson Helton Santos Bueno
American Coatings Association 2020 Abstract The aim of the present work is to evaluate the corrosion resistance of epoxy-Nb2O5 paint in acid atmosphere and high temperatures. For comparison, samples of SAE1020 carbon steel were coated with an epoxy-Nb2O5 paint and an epoxy commercial paint. The samples were partially immersed for 720 h and 1440 h in 40% (v/v) H2SO4 solution at temperatures of 25C, 60C, and 80C. The degradation analysis, mechanical characterization, and electrochemical measurements of the samples were carried out after immersion period. The coatings were characterized by scanning electron microscopy. Electrochemical impedance spectroscopy was used to evaluate the electrochemical behavior. Results showed the epoxyNb2O5 paint was less blistering, cracked, flaked, and rusted than the commercial epoxy paint samples. However, it was important to note that the increase in temperature led to the degradation of epoxy-Nb2O5 paint. The addition of temperature was probably responsible for the degradation of epoxy resin over the immersion time. Keywords Niobium pentoxide, Epoxy coating, Anticorrosive coatings, High temperatures, Sulfuric acid M. E. D. Serenario (&), B. A. F. Santos, A. H. S. Bueno Federal University of Sa˜o Joa˜o del Rei (UFSJ), Sa˜o Joa˜o del Rei, Brazil e-mail: [email protected] B. A. F. Santos e-mail: [email protected] A. H. S. Bueno e-mail: [email protected] L. R. M. Miranda Catholic University of Petro´polis, Petro´polis, Brazil e-mail: [email protected]
Introduction Methodologies have been proposed to solve the problems caused by corrosive processes. The industrial painting technique plays a role in the anticorrosion protection methods due to excellent versatility, ease of application, easy maintenance, and acceptable costs; it can be used as a protective alternative against several types of corrosive agents.1 In recent years, technological development in the coating area has been intense, and the results obtained with industrial paint in the scope of anticorrosive protection are very representative; however, the main coatings on the industrial market cannot fully protect the metallic substrate in highly aggressive environments.2 Epoxy coatings have been widely used because of their versatility, excellent chemical resistance, adhesion on metallic substrates, and high durability. Nevertheless, epoxy coatings are susceptible to electrolyte penetration and may suffer long-term degradation. Thus, several studies aim to modify the epoxy coatings with the incorporation of anticorrosive pigments and solid particles to reduce defects at the interface between the epoxy resin and the metallic substrate.3–5 Niobium pentoxide (Nb2O5) has been highlighted as an anticorrosive pigment and as an additive in materials
Data Loading...
