INFLUENCE OF STEEL CONTAMINATION IN PETROLEUM PRODUCTS ON FORMATION OF NON-METALLIC INCLUSIONS

It is generally recognized that the high content of non-metallic inclusions in structural steels alter their physical and mechanical properties. Formation of non-metallic inclusions is a complex phenomenon that depends on the composition, pressure and temperature of the working media. By use of different surface analysis techniques we analysed an austenitic stainless steel pipe that has been contaminated by petroleum products as a result of diffusion and concluded that the liquid medium penetrates relatively far into the metal by adsorptive migration, resulting in formation of chemically active sites that promote the formation of intermetallic compounds. It is important to understand this mechanism as it directly influences corrosion and further failure of the steel, leading to problems that translate into human and economic losses.