Carbon Diffusion Between the Layers in Modern Pattern-Welded Damascus Blades

• Published in: Materials characterization Vol. 41; no. 5; pp. 183 - 191
• Main Authors: Verhoeven, John D., Clark, Howard F.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.11.1998; Elsevier Science
• Subjects: Applied sciences; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Metals. Metallurgy; Other heat and thermomechanical treatments; Physics; Treatment of materials and its effects on microstructure and properties; Forge welding; High carbon steel; Low carbon steel; Theoretical study; Metallography; Chemical etching; Hardness; Experimental study; Carbon; Forging; Carbon content; Dual-phase steels; Diffusion equation; Steels; Diffusion coefficient; Diffusion; Microstructure; Compounded structure
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/S1044-5803(98)00035-7

Pattern-welded Damascus steel blades are made by forge welding together pairs of steels having low- and high-carbon compositions. It is often assumed that these blades consist of hard and soft layers owing to the carbon variations of the original steels and that it is this difference in hardness that produces the etching characteristics that give the surface patterns. Theoretical arguments are presented that show that, with the modern forging techniques used to make these blades, carbon diffusion should be adequate to homogenize the C level between the layers of the blades, which predicts no hardness difference between layers. Experiments are presented on several modern blades, showing that there are no hardness differences found between layers. Arguments are presented for a theory that it is the difference in alloying elements between the layers that produces the differential etching characteristics that give rise to the visual surface patterns of most contemporary pattern-welded Damascus steels.