High-speed rail axle with long fatigue life and speed of not less than 400 kilometers per hour, and laser quenching method of high-speed rail axle

A technology of laser quenching and fatigue life, which is applied to axles, wheels, vehicle parts, etc., can solve the problems of low fatigue performance and inability to meet the application requirements of high-speed rail axles, achieve surface hardness and strength improvement, good and uniform cooling, and reduce effective tension The effect of stress

Active Publication Date: 2021-01-05
MAANSHAN IRON & STEEL CO LTD
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The disadvantage is that the key indicators such as residual stress and fatigue strength on the surface of the axle after laser quenching are not characterized. From the test results of the Rockwell hardness (70-85HR15N, converted into Vickers hardness of about 237-492HV) on the surface of the axle after laser quenching It is estimated that its fatigue performance is low and cannot meet the application requirements of high-speed rail axles with a speed of ≥400 kilometers per hour

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • High-speed rail axle with long fatigue life and speed of not less than 400 kilometers per hour, and laser quenching method of high-speed rail axle
  • High-speed rail axle with long fatigue life and speed of not less than 400 kilometers per hour, and laser quenching method of high-speed rail axle
  • High-speed rail axle with long fatigue life and speed of not less than 400 kilometers per hour, and laser quenching method of high-speed rail axle

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] A laser quenching method for high-fatigue life and speed ≥ 400 kilometers per hour for high-speed rail axles, comprising the following process:

[0040] Axle blank forging→rough turning of rough axle→axle end face processing→heat treatment process→axle outer circle finish turning process→axle inner hole boring processing→cylindrical grinding→flaw detection→laser quenching→cylindrical grinding.

[0041] See Table 1 for the weight percentages of the chemical components of the high-fatigue life and speed ≥ 400 kilometers per hour high-speed rail axle described in Example 1. The balance not shown in Table 1 is Fe and unavoidable impurities.

[0042] The above heat treatment process includes: normalizing + quenching + high temperature tempering;

[0043] Specifically: normalizing process: heat the steel for high-speed rail axles to 920°C, keep it warm for 5 hours, and then air-cool it to below 400°C;

[0044] Quenching process: heat the high-speed rail axle steel after nor...

Embodiment 1-3

[0062] Table 4 Embodiment 1-3 laser quenching process

[0063]

[0064] 6) Fine grinding the surface of the axle after laser quenching.

[0065] Embodiment 2-Example 3 and Comparative Example 1 adopt the same composition and production method as Example 1, the difference is that the laser quenching process of Example 2-Example 3 is different from Example 1; The same quenching process parameters, the difference is that the composition and heat treatment process of Example 4 are different from those of Example 1; Comparative Example 1 does not use laser quenching, and Comparative Example 2 adopts the same quenching process parameters as Example 1, the difference is that Comparative Example 2 Composition and heat treatment process are different from embodiment 1. The laser quenching process of each embodiment and comparative example is shown in Table 4.

[0066] Embodiment 1-4 (after laser quenching) and comparative example 1 (not carrying out laser quenching), comparative e...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
hardnessaaaaaaaaaa
fatigue strengthaaaaaaaaaa
lengthaaaaaaaaaa
Login to view more

Abstract

The invention provides a high-speed rail axle with a long fatigue life and a speed of not less than 400 kilometers per hour, and a laser quenching method of the high-speed rail axle. The method comprises the following steps: a quenching machine tool is vertical, the axle is vertically placed, a laser device is axially vertical to the axle, and the spot size is kept stable in a laser quenching process; a plurality of rows of gas nozzles are formed at different angles to ensure good and uniform cooling at an R-angle transition part of the axle; the depth H of a hardening layer is selected to be1.0-2.0mm, the laser output power P is 2000-8000W, the laser scanning speed is 500-1300mm/min, and the laser overlapping rate is controlled between 30% and 40%. Compared with the prior art, after theaxle is subjected to the heat treatment of normalizing, quenching and high-temperature tempering, laser quenching is carried out on the whole length of the axle, and after the laser quenching, the surface hardness is not less than 630 HV, the surface residual compressive stress exceeds -800 MPa, and the fatigue strength exceeds 690 MPa.

Description

technical field [0001] The invention belongs to the technical field of high-speed rail axles, and in particular relates to a high-speed rail axle with a high fatigue life and a speed ≥ 400 kilometers per hour and a laser quenching method thereof. Background technique [0002] The axle is a super-large stepped axisymmetric part with a maximum diameter of more than 200mm and a length of up to 2320mm. It forms a wheel set through an interference connection with the wheel and bears the full weight of the rolling stock. It is one of the three key parts of the railway vehicle. . Heavy-duty and high-speed trains are the key development directions of high-speed trains. The axle is the heaviest key moving part of a single body. Improving fatigue performance is the eternal theme of axle steel research and development. [0003] Due to the different national conditions and technical viewpoints of different countries, the axle materials selected are not the same. From the practice of f...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C21D1/09C21D1/18C21D1/28C21D1/74C21D6/00C21D9/28C22C38/02C22C38/04C22C38/06C22C38/42C22C38/44C22C38/46B60B35/00
CPCC21D1/09C21D1/18C21D1/28C21D1/74C21D6/004C21D6/005C21D6/008C21D9/28C22C38/02C22C38/04C22C38/002C22C38/44C22C38/46C22C38/42C22C38/06B60B35/00C21D2211/009C21D2211/001C21D2211/008
Inventor 陈世杰汪开忠胡芳忠杜松林杨志强吴林郝震宇
Owner MAANSHAN IRON & STEEL CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products