Features of Morphology of Carbide Banding of High-Carbon Steels with Bulat Structure

The main structural differences between the 18th century Persian Bulat knife and the modern knife made of Kh (ShKh15) type bearing steel are considered. Qualitative and quantitative characteristics of carbide banding of high-carbon steels manufactured using Damascus steel technologies have been established. The nature of carbide banding is described in detail based on the shape of the planar projection lines of Bulat (Damascus) structure. Studies have confirmed that the matrix structure of tempered martensite and lamellar troostite is isometric and is not oriented in the direction of deformation. The carbide structure of steels manufactured using Damascus steel technologies is strongly oriented in the direction of deformation. It is calculated that the degree of orientation of linear elements in the two-dimensional metallographic specimen plane approaches unity. The regular layered banding (score 4) patterns are consistent with the structure of the Eastern genuine Damascus steels having an increased content of phosphorus admixture (0.1–0.3% P). The Damascus structure of alloyed tool steels is characterized by uneven reticular-fibrous carbide banding patterns (score 5).