Corrosion is the unwanted destruction of a material due to reaction with the surrounding
environment. This phenomenon causes damage from various aspects in industries and
facilities. Therefore, investigating ways to prevent corrosion is one of the important
industrial issues. The use of organic coatings is one of the most widely used corrosion
protection methods. Due to the applicability of epoxy resin in the industry, The organic
coating used in this research is prepared based on epoxy resin, And to improve its anticorrosion
property, a natural corrosion additive that is cost-effective and environmentally
friendly has been used.
In this research, the effect of adding powder and extracts of Cystoseira brown algae and
Laurencia red algae to pure epoxy coating in order to investigate the corrosion protection
performance using Electrochemical Impedance Spectroscopy (EIS) and Tafel polarization
in sodium chloride solution 3.5 % was investigated. Surface morphology was investigated
using scanning electron microscope (FESEM). Fourier transform infrared spectroscopy
(FTIR) was used to identify functional groups in algae. The thermal properties of the
coatings were investigated using the TGA test, and the results show that algae do not affect
the thermal stability of the epoxy coating.
In order to investigate the effect of algae powder and extract on the corrosion process,
Epoxy coating without and with the addition of different percentages of algae powder and
extract was investigated on carbon steel ST12 in 3.5% sodium chloride solution at different
immersion times. The results of electrochemical impedance spectroscopy showed that the
coatings containing algae powder showed higher resistance than the extract with the
passage of immersion time. In the stage of checking the percentage of algae powder, In the
stage of checking the percentage of algae powder, it was found that coatings containing 1%
brown algae powder showed higher resistance in reducing the corrosion process