Investigating of Factors Affecting the Corrosion Protection of Epoxy Primer containing Calcium Hydrogen Orthophosphate and Nano Silica Using Taguchi Method

The current essay analyzes the anti-corrosion properties of epoxy primers including anti-corrosion pigment calcium hydrogen orthophosphate and hydrophobic nano silica with various percentages optimized by Taguchi experimental design. The impact of influential factors such as the percentage of anti-corrosion pigments, percentage of nano silica and pigment to binder ratio on anti-corrosion properties of epoxy primer based on model L9 Taguchi method was considered and analyzed. The anti-corrosion pigments and nano silica were initially dispersed into epoxy resin, the samples for corrosion testing were practiced on metal panels. Furthermore, a main sample is identified to be compared with the samples chosen by Taguchi experimental method. Electrochemical impedance spectroscopy (EIS) is applied to study the corrosion inhibition performance of the primers in 3.5% NaCl aqueous solution and salt spray test. To figure out the distribution of nano silica, particles in epoxy resin were detected by scanning electron microscope (SEM). The outcomes achieved in this work revealed that solubility of pigment and corrosion inhibition are significant factors influencing corrosion resistance of the epoxy primer. Generally, it is proved that adding nano silica to epoxy primer made the number of blisters and corrosion products diminish after being exposed to corrosion test. The most appropriate results of the corrosion resistance tests presented in the sample embracing the epoxy primer loaded with 6.5% calcium hydrogen orthophosphate, 3% nano silica and pigment to binder ratio of 1.