Anti-corrosion performance of alumina nano-fillers incorporated in epoxy-resin coatings
The anticorrosive performance of alumina/epoxy nanocomposite was examined by EIS & LP tests. Using flat cell assemble. The working volume was 350 mL. SCE used as RE. Graphite plate, with dimension 25 x 25 x 5 mm, and 2.6 cm2 exposed area, used as CE. Steel coated by epoxy-resin and alumina/epoxy nanocomposite, with dimension 25 x 25 x (12.6 mm, + the coating thickness), and 2.6 cm2 exposed area, as WE. The electrolyte used was 3% NaCl used with DI water. The potentiostat used is VMP3. OCP was recorded for 24, 48, 72, 96, and 120 h, before and during each test. After OCP completion of each step, EIS & LP were measured. For EIS, the frequency sweep was from 100 KHz to 100 mHz, with 20 mV AC amplitude, and for LP, the voltage ranges from -250 mV to 250 mV, with 1 mV/sec scan rate. The test has been carried out on pure epoxy-resin, 0.5 wt. %, & 1 wt. % alumina/epoxy nanocomposite. Metal sample, without coating, was tested by LP, after 6 h OCP. The EIS data that are being collected were analyzed using Nyquist plot (with an equivalent circuit model - as found in the manuscript). While LP data were analyzed using tafel slope.