Corrosion inhibition mechanism and corrosion prediction models of NTO-based PBX against medium carbon steel

Polymer-bonded explosive (PBX) systems incorporating 3-nitro-1,2,4-triazol-5-one (NTO) have attracted significant research interest due to their excellent insensitive properties and detonation characteristics. This study prepared three distinct NTO-based PBXs (N-PBXs) under varying compression molding pressures (1800, 2200, and 2500 kg cm⁻²) to evaluate corrosion inhibition mechanism against medium carbon steel (MCS) under elevated temperature/humidity conditions. The N-PBXs follow the same corrosion-inhibition law. In the initial stage of corrosion, the amount of exposed NTO on the bottom of the N-PBXs has been the key step to determine the corrosion-inhibition dynamics. With the extension of corrosion periods, the migration efficiency of NTO from the internal pore structure was the key step in determining the corrosion rate. Corrosion pit depth progression was fitted as a classical prediction algorithm (power function) as a function of exposure duration. The N-PBX with compression molding pressure of 2200 kg·cm⁻² exhibits the highest corrosion-inhibition efficiency (87.75 %) against MCS and maintains stability with the corrosion periods.