Desenvolvimento de estruturas do tipo bi-camada baseadas em camadas auto-organizadas e polianilina para a proteção contra a corrosão de ligas de alumínio / Development of structures such as bi-layer based on self-assembled monolayers and polyaniline for corrosion protection of aluminum alloys
AUTOR(ES)
Daiane Piva Barbosa da Silva
DATA DE PUBLICAÇÃO
2010
RESUMO
A method widely used in corrosion protection of aluminum alloys is the formation of conversion layers of chromium. In search of "environmentally friendly" corrosion protection methods there is the possibility of using conducting polymers such as polyaniline (PAni), which can act by barrier effect or absorbing charged particles from the solution and / or self-assembled monolayers (SAM), where protection may occur indirectly, when the SAM acts as a promoter of adhesion to other coatings, or directly, when the monolayer blocks the access of aggressive substances to the surface. This work proposes the use of bi-layers based on propyl-trimethoxy-silane (PTMS) + PAni and octadecyl-trimethoxy-silane (ODTMS) + PAni for corrosion protection of aluminum alloys AA1050, AA2024 and AA7075. For the corrosion tests were used different techniques such as: open circuit potential, potentiodynamic polarization curves and electrochemical impedance spectroscopy. Analysis of optical microscopy and scanning electron microscopy (SEM) were performed before and after the corrosion tests in order to verify the efficiency of the proposed coatings in corrosion protection. Additionally, tests of salt spray and adhesion were made, in addition to the characterization of the alloys by SEM and X-ray dispersive energy. The results show that the treatments resulted in improvements in corrosion resistance in the following order: PTMS sam pani alumínio sam proteção contra a corrosão pani protection against corrosion aluminum
ASSUNTO(S)
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