Turmeric as eco-friendly corrosion inhibitor for electron beam-curable steel coating in 3.5% sodium chloride solution

Purpose This study aims is to evaluate the environmentally friendly turmeric as a corrosion inhibitor for mild steel in a simulated seawater corrosion medium such as a 3.5% NaCl solution. To accomplish this, different proportions of turmeric (0.3, 0.6, 0.9 and 1.5%) were added to solvent-free epoxy-acrylate resin-based coating formulations. Then, all the formulations were sonicated and coated as thin films on different substrates; these coated films were then polymerized under a dose of 10 kGy of electron beam (EB) radiation. Design/methodology/approach Various properties of all cured coating films such as Fourier transform infrared spectroscopy, water contact angle, thermogravimetric analysis and scanning electron microscopy were studied, in addition to their physical, chemical and mechanical properties. Turmeric was then evaluated in these formulations as an anticorrosion agent for mild steel in 3.5% NaCl. The different corrosion-resistant properties of all EB-cured coating films were evaluated by open circuit potential measurements, rust degree, blistering, adhesion loss at X-cut and weight loss measurements. Findings The results showed that most of the formulations are homogeneous, especially at low concentrations of turmeric, and their films have high-performance properties. Originality/value It was also found that the formulation containing 0.6% of turmeric per 100 g of coating was considered the best formulation as it gave the highest protection to the mild steel plates with no negative effects on the chemical and physical properties of their films.