HIGH TOUGHNESS BAINITIC STEEL WHEEL FOR RAIL TRANSIT, AND MANUFACTURING METHOD THEREFOR

摘要

A high toughness bainitic steel wheel for rail transit, and a manufacturing method therefor. The wheel includes the following elements by weight percentage: carbon (C): 0.10-0.40%, silicon (Si): 1.00-2.00%, manganese (Mn): 1.00-2.50%, nickel (Ni): 0.20-1.00%, rare earth (RE): 0.001-0.040%, less than or equal to 0.020% of phosphorus (P), and less than or equal to 0.020% of sulphur (S), the remainder being iron and unavoidable residual elements, 1.50% ≤ Si+Ni ≤ 2.50%, 2.00% ≤ Si+Mn ≤ 4.00%. Via steel chemical composition design and manufacturing processes, the wheel rim has a carbide-free bainitic structure, the spokes and hub have a mainly granular bainitic and saturated ferritic microstructure, and the wheel has comprehensive mechanical properties such as high yield strength, toughness and low-temperature toughness, and good service usage properties. In addition, costs are reduced, and the service life and comprehensive benefits of the wheel are improved.