Bainite steel wheel for rail traffic passenger car and manufacturing method thereof

Abstract

The invention discloses a bainite steel wheel for a rail traffic passenger car and a manufacturing method thereof. The bainite steel wheel comprises the chemical components of 0.08-0.35% of C, 0.10-1.50% of Ni, 0.25-1.50% of Cr, 0.70-2.10% of Mn, 0.20-1.00% of Si, 0.01-1.00% of W, 0.05-0.60% of Mo, 0.01-0.80% of Cu, 0.01-0.20% of V, 0.001-0.20% of Nb, 0.0001-0.0350% of B, 0.001-0.040% of RE, 0-0.020% of P, 0-0.020% of S, and the balance Fe and inevitable residual elements, and in addition, the sum of Mn and Cr is larger than or equal to 2.0% and smaller than or equal to 3.0%. According to thebainite steel wheel for the rail traffic passenger car and the manufacturing method thereof, the novel C-Ni-Mn-Cr-Mo alloy design system and the alloying principle are adopted, after the wheel is formed, advanced heat treatment is conducted, then, the carbide-free bainite structure of a rim is obtained, and the wheel has the characteristics of being excellent in comprehensive mechanical property,corrosion resistance and service performance, high in strength, hardness, toughness, wheel rail rolling contact fatigue (RCF) resistance and hot crack resistance, and the like.

Description

technical field [0001] The invention belongs to the technical field of rail transit, and relates to a bainitic steel wheel for a rail transit passenger car and a manufacturing method thereof, in particular to a non-carbide compound for a rail transit passenger car with an axle load of ≤18t and a running speed of ≤160km / h or an urban rail Bainitic steel wheel and method of manufacture thereof. Background technique [0002] Wheels are the "shoes" of rail transit and one of the most important walking parts, which directly affects the safety of operation. Judging from the types of wheels currently used at home and abroad, the C content of passenger car wheels is generally below 0.65% (CL60 in China, with a C content of 0.55-0.65%; the highest C content in Europe is the ER9 wheel in the EN13262 standard, and the upper limit of the C content is 0.60%) , the yield strength is lower than 650MPa, and the hardness is lower than 290HB (significantly lower than the rail hardness). Due...

AI Technical Summary

Problems solved by technology

[0008] (1) The yield strength of the rim is low, generally not exceeding 650MPa. Because the rolling contact stress between the wheel and the rail is large during the operation of the wheel, sometimes exceeding the yield strength of the wheel steel, the wheel is plastically deformed during operation, resulting in the subsurface of the tread Plastic deformation occurs, and because there are brittle phases such as inclusions and cementite in the steel, it is easy to cause micro-cracks on the rim, and these micro-cracks will produce defects such as peeling and rim cracking under the action of rolling contact fatigue of the wheel.

[0009] (2) The carbon content in the steel is high and the thermal damage resistance is poor

[0010] (3) Poor hardenability of wheel steel

There is a certain hardness gradient in the rim of the wheel, and the hardness is uneven, which is prone to defects such as rim wear and out-of-roundness

[0011] (4) It does not contain corrosion-resistant alloy elements, the oxide scale on the surface of the wheel has poor ability to resist damp heat and corrosive environments, and the chemical electrode potential difference between ferrite and cementite is large, which is easy to generate corrosion micro-batteries, resulting in the overall corrosion resistance of the wheel Difference

[0012] (5) Under low temperature conditions, the toughness of the wheel drops significantly. Once a crack source is generated, it will expand rapidly and eventually form a crack and break

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