Analysis of mechanical and anti-corrosion properties of polymer nano-composite coating on structural steel

The primary aim of this study is to develop and analyse a hybrid nanomaterial combining Boron nitride and multi-walled carbon nanotubes (MWCNTs) at various concentrations (0.1wt%, 0.5wt%, and 1.0wt%). Using a dip coating method and epoxy as the matrix, a coating was applied to mild steel substrates. Additionally, the surfaces of the coated substrates were examined using XRD and FTIR analyses. The hydrophobicity was assessed with a contact angle test, and the adhesion to the substrate was evaluated through a crosshatch adhesion test. After analysing the surface properties of the coating, nano-indentation tests were performed to determine mechanical characteristics such as hardness and modulus of elasticity. The corrosion rates were measured via Tafel plot analysis in a solution containing 0.5 M and 3.5wt% NaCl. Following a comprehensive analysis, it was concluded that the hybrid sample with a composition of 0.25wt% Boron Nitride and 0.25wt% MWCNT in epoxy is the most optimal formulation. The contact angle of this sample was recorded at 41.693°. It also exhibits a hardness of 0.31904765 GPa and a modulus of elasticity of 6.5809 GPa. Furthermore, the corrosion rate was determined to be 0.5761443 mils/year, which is notably lower than that of other samples.