Influence of the Elevated Contents of Silicon and Manganese on the Operating Characteristics of High-Strength Wheel Steel

Abstract

We study the temperature dependences of strength and plasticity, the cyclic crack-growth resistance after the thermal and force loading in the course of braking, and the wear and damage resistances of wheel steels with elevated contents of silicon and manganese and lowered contents of carbon and compare these characteristics with the earlier determined characteristics for standard 2 and T steels. It is shown that silicon and manganese promote the leveling of cyclic fracture toughness of steels in different zones of the wheel rim and the decrease in the high-temperature (above 500°С) plasticity (elongation), which reduces the susceptibility of steel to the formation of slid flats on the rolling surface of the wheel. However, the solid-solution hardening of these steels observed for relatively high (∼ 0.6%) carbon contents results in a low crack-growth resistance under cyclic loading in the initial state and under the influence of thermal and force factors under the conditions of braking, as well as in the low damage resistance under the conditions of contact fatigue. We recommend to reduce the carbon content in these steels down to 0.52–0.53%.