The Relation between Structure and Corrosion Protection Performance of Hybrid Nanonanofibrous silica/Sol-Gel Film

Abstract

The purpose of this work is to study the effect of nanofibrous SiO2 on the corrosion protection performance of the sol-gel film coated on AA5052 aluminum alloy. The structure and surface morphology of the hybrid film ware evaluated by Transmission electron microscope (TEM) and Scanning electron microscopy (SEM), the result highlighted that the surface of composite films appears uniform and the nanofibrous SiO2 was evenly dispersed in the film. By analyzing the results of infrared spectroscopy, the addition of nanofibrous SiO2 enhanced the cross-linking of the sol-gel film. The electrochemical behavior of coated samples was determined by electrochemical test. The corrosion protection performance of the sol-gel film had a great improvement with addition of nanofibrous SiO2, the optimal additive concentration was 1 mg/ml at which the hybrid film showed the best corrosion protective performance in 3.5% NaCl solution. From the result of potentiodynamic polarization, the corrosion rate of sample coated with the sol-gel film with 1 mg/ml nanofibrous SiO2 was about 6 times slower than pure sol-gel film coated sample.

Depósito por aspersión de una capa protectora de SiO2–PMMA sobre acero AISI 1036 con propiedades de barrera a contaminantes atmosféricos

“…Al evitar la fractura durante el curado de la película híbrida, se garantiza que los sustratos metálicos estén protegidos de procesos corrosivos. Al respecto, se ha reportado la obtención de películas híbridas por el método de screen printing usando tratamientos térmicos de secado de 1 h a 80 °C y continuando en algunos casos con procesos de calcinación de 500 °C [21,22]. En el caso de recubrimientos híbridos a base de Dióxido de silicio-Polimetilmetacrilato (SiO2-PMMA), se ha reportado su efectividad como material anticorrosivo, aunque habitualmente se utilizan los métodos de aplicación de spin-coating o dip-coating, con procesos de secado de 40 -70 °C por 24 h, seguidos de un proceso de curado de 1 a 3 h a temperaturas de 120 -160 °C [23][24].…”