Heat-treating process of high-speed train axle containing niobium and titanium

Abstract

The invention disclose a steel for a high-speed train axle containing niobium and titanium, and the steel comprises the chemical components based on the mass percentage (wt%): 0.25-0.32 wt% of C, 0.15-0.40 wt% of Si, 0.60-0.90 wt% of Mn, no more than 0.015 wt% of P, no more than 0.010 wt% of S, 1.00-1.20 wt% of Cr, 0.20-0.35 wt% of Mo, 0.15-0.30 wt% of Ni, 0.02-0.04 wt% of V, 0.015-0.040 wt% of Nb, 0.10-0.30 wt% of Cu, 0.0008-0.0050 wt% of B, and 0.010-0.050 wt% of A1S, after the axle prepared by the components is thermally treated, the grain size is no less than 8.5 grades, and the tissue is tempered sorbite+bainite, wherein the content of the tempered sorbite adjacent to the axle surface is about 70-90%, and the the content of the tempered sorbite at the 1 / 2 radius of the axle is about 40-60%.

Description

technical field [0001] The invention belongs to the field of axle steel, in particular to the technical field of alloy structural steel for high-speed train axles and heat treatment technology thereof. Background technique [0002] The axle is the key part of the vehicle's walking part. It bears the self-weight and load of the vehicle. It also bears the impact force and braking force when the vehicle is running and parking. The force situation is more complicated under high-speed and heavy-load conditions. It is a key component of railway construction. One of the three key parts (heavy rails, axles and wheels), the train axle is a super-large axisymmetric stepped shaft part with a maximum diameter of about 200mm and a length of about 2200mm. [0003] With the operation of high-speed railways in my country, the speed of trains has further increased. As one of the key components of railway trains, high-speed axles are important running components of railway trains, and their q...

AI Technical Summary

Problems solved by technology

Some European high-speed axle materials use high-alloy structural steel such as 30NiCrMoV12, which contains Cr0.60~1.00%, Ni2.70~3.30%, Mo0.40~0.60%, V0.08~0.13%, and there are many types of steel Advantages such as good hardenability, oil quenching, small deformation, high hardness, high yield ratio, good corrosion resistance, etc., but the cost is relatively high

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