Corrosion Protection of Additively Manufactured H13 Tool Steel in 1.0 M HCl Using 1-Benzyloxynaphthalene as an Organic Inhibitor: electrochemical measurements characterization and computational approaches

This paper explores the anticorrosive potential of 1-benzyloxynaphthalene (BN) for protecting the surface of 3D-printed H13 tool steel produced via the Selective Laser Melting (SLM) process in a 1.0 M HCl medium. BN was synthesized through the O-alkylation of 1-naphthol with benzyl chloride via a nucleophilic substitution reaction. The reaction was conducted in the presence of potassium carbonate (K2CO3), which deprotonates the hydroxyl group of 1-naphthol, thereby generating the more nucleophilic naphtholate ion. After synthesis part, the characterization of this anticorrosive agent was performed using Fourier Transform Infrared (FTIR), Mass spectrometry (MS) and Nuclear Magnetic Resonance (NMR) spectroscopies. The electrochemical part was performed on H13 tool steel using Electrochemical Impedance Spectroscopy (EIS), Potentiodynamic Polarization (PDP), and Scanning Electron Microscopy (SEM). The charge transfer resistance showed a significant increase with increasing BN concentrations. The corrosion inhibition efficiency improved with increasing BN molarity, reaching a maximum of 91.40% at 2 × 10-3 M. SEM analysis revealed a smoother surface in the presence of BN, indicating effective protection against H13 tool steel corrosion. Density Functional Theory (DFT) calculations provided insights into the electronic structure and active sites responsible for the inhibition efficiency of BN. Additionally, molecular dynamics simulations were employed to further investigate the interaction of BN with the H13 steel surface in a 1.0 M HCl environment. Computational results indicated significant adsorption energies, reflecting strong molecular-level interactions that correlate with the observed high anticorrosion efficiency of BN in experimental conditions.