Special features of the fracture of ordered segregated excess cementite in eutectoid steels

Special features of plastic deformation and fracture of excess cementite segregated under the conditions of high-temperature carbon supersaturation of steel are studied by the methods of light and scanning electron microscopy. It is shown that regularly oriented flakes of excess cementite with a lamellar structure are formed within the former austenite grains. The cementite flakes oriented along the rolling plane fracture by a brittle mechanism forming numerous fragments. The behavior of free cementite under the conditions of cold rolling depends on the orientation of the flakes in the specimen. The mutual shift of the layers allows coarse cementite formations to deform under the action of compressive stresses without cracking.