Effect of chemical composition on the hardenability of high-strength rail steel

1. The hardenability nomograms developed for high-strength rail steels make it possible to select the composition of steel with a given hardenability, the minimal permissible value of which depends on the operating conditions. 2. An even structure of martensite in the head of the rail to a depth of 12–15 mm from the rolling surface (under modern operating conditions) is achieved by complex alloying of high-carbon steel with chromium, silicon, and manganese at a total concentration of at least 2.8 at.%. 3. On the basis of the results we recommend the following chemical composition for high-strength rails with differentiated strength through the section: 0.75–0.85% C, 1.0–1.2% Mn, 0.3–0.5% Si, 1.2–1.5% Cr, and 0.005% Ti or 0.03–0.08% V.