Bainite steel wheel for rail traffic truck and manufacturing method of bainite steel wheel

Abstract

The invention discloses a bainite steel wheel for a rail traffic truck and a manufacturing method of the bainite steel wheel. The bainite steel wheel for the rail traffic truck comprises the followingchemical components: 0.10-0.40% 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, less than or equal to 0.020% of P, less than or equal to 0.020% of S and the balance of Fe and inevitable residual elements; and moreover, 2.0%< / = Mn+ Cr< / = 3.0%. A novel alloy design system of C-Ni-Mn-Cr-Mo and an alloying principle are adopted, after wheels are formed and subjected to advanced heat treatment, a carbide-free bainite organization structureis obtained, and the wheels have excellent integrated mechanical property, corrosion resistance and service performance, and particularly have the characteristics of high strength, hardness and toughness, high wheel track rolling contact fatigue (RCF) resistance, hot crack resistance and the like.

Description

technical field [0001] The invention belongs to the technical field of rail transit, and relates to a bainite steel wheel for rail transit trucks and a manufacturing method thereof, in particular to a rail with an axle load not greater than 35 tons, a wheel diameter of 760mm to 970mm, and a running speed of ≤160km / h Carbide-free bainitic steel wheels for transportation trucks and methods 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. During the normal operation of the train, the wheel bears the full load of the vehicle and is damaged by wear and rolling contact fatigue (RCF for short). The very complex action relationship is always in a dynamic and alternating stress state, especially the wheels and rails, wheels and brake shoes are two pairs of friction pairs that exist all the time and cannot be ignored; in emergency situations or spec...

AI Technical Summary

Problems solved by technology

[0011] (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 and alternately changes during the operation of the wheel, sometimes exceeding the yield strength of the wheel steel, the subsurface of the wheel rim tread produces plasticity during operation Deformation, and because there are brittle phases such as inclusions and cementite in the steel, it is easy to cause micro-cracks in the rim. These micro-cracks will produce defects and failures such as peeling and rim cracks under the action of rolling contact fatigue during wheel operation.

[0012] (2) The carbon content in the steel is high and the thermal damage resistance is poor

[0013] (3) The wheel steel is carbon steel with poor hardenability

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

[0014] (4) The ability of the oxide scale on the surface of the wheel to resist damp heat and corrosive environment is poor, and the chemical electrode potential difference between ferrite and cementite is large, which is easy to generate corrosion micro-batteries, resulting in poor overall corrosion resistance of the wheel

[0015] (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

Images