Corrosion of stainless steel coated with a ZrO2 film in a hydrogen sulfide gas environment

Abstract

A zirconia sol was prepared by the sol–gel method and coated on the surface of stainless steel substrates. The gas corrosion test was carried out for the stainless steel substrates and for the coated samples using a high-temperature and high-pressure reactor. The coated samples and the substrates were placed in the reaction kettle, and it was filled with the H2S gas at the pressures of 0.6, 0.8, and 1 MPa. After standing at room temperature for 24 h, the samples were observed by optical microscopy and a scanning electron microscopy, and it was found that as the pressure increases, the corrosion of the stainless steel substrates are more severe, while the film samples show only slight pitting corrosion. The experimental results show that in the corrosive H2S gas environment, the stainless steel samples coated with the ZrO2 film can effectively block the H2S gas corrosion on the stainless steel substrate and reduce the hydrogen bubbling and hydrogen-induced cracking caused by gas corrosion. This finding has important practical significance for improving the service life of oil pipelines and reducing the occurrence of oil spills and other accidents.