Hydrogen brittleness of 08Kh13 corrosion-resistant steel

Abstract

In the modern petroleum refining industry, corrosion resistant steels are widely used for the purpose of reducing losses of equipment metal from corrosion. It is known that at increased service temperatures the development of hydrogen corrosion, in which hydrogen penetrating into the metal and interacting with the metal carbides forms methane, as the result of which the steel is decarburized and cracks, is possible. At lower temperatures the corrosion-active impurities normally present in petroleum products promote not only the development of corrosion processes but also ease of penetration of hydrogen into the metal even at low temperatures. Hydrogen absorption by metal, especially of ferritic steels, is accompanied by formation of separations, air holes, and by the appearance of hydrogen brittleness. The tendency of 08Kh13 steel toward hydrogen brittleness is discussed. The studies showed that the material in the zone of the defect failed brittlely in impact. The fragments formed of the pipe wall had almost the form of rectangles. The chemical analysis of the investigated steel (%) was 0.08 C, 13.74 Cr, 0.015 S, 0.16 Mn, 0.21 Ni, 0.41 Cu. The chemical analysis of the steel meets the requirement for 08K13 ferritic chromium steel.