Protective properties of commercially available hydrogen coatings applied to differently prepared substrates

Hydrogen has recently been increasingly mentioned as an alternative energy source due to its characteristic that it releases water as a combustion product and not carbon dioxide, which is an important factor in the fight against global warming. Due to its extremely small molecular size, many obstacles need to be overcome in order for hydrogen to be introduced as a commercial energy source. One of the biggest problems with hydrogen is hydrogen embrittlement, which occurs when hydrogen interacts with carbon steel in pipelines and can be extremely harmful. One way to prevent this is with coatings designed to protect against hydrogen. Two different commercial coatings were tested, each applied in one or two layers, and two surface treatment processes, laser cleaning and sandblasting, were compared, which were subjected to various physical and electrochemical tests before and after exploitation in humidity and climatic chambers. Physical tests consisted of measuring the hardness, adhesion and gloss, while electrochemical tests measured E corr , and the resistance of the coating was tested by electrochemical impedance spectroscopy (EIS), during which the samples were immersed in 3.5% NaCl aqueous solution at a temperature of 20°C. The tested coatings improve mechanical and anticorrosive properties, which means that they provide good resistance to internal mechanical influences and effectively prevent corrosion and degradation of metal surfaces during exploitation in gas pipelines.