CN101713050A - Steel for large power locomotive traction gear - Google Patents

Abstract

This invention discloses steel, in particular to steel for large power locomotive traction gear. The steel comprises the following components in mass percent: 0.16 to 0.21 percent of carbon, 1.50 to 1.80 percent of chromium, 1.50 to 1.70 percent of nickel, less than 0.40 percent of silicon, 0.50 to 0.90 percent of manganese, less than 0.020 percent of sulfur, less than 0.020 percent of phosphor, 0.25 to 0.35 percent of molybdenum, and balance of iron, wherein hydrogen content is not more than 2 ppm; and oxygen content is not more than 20 ppm. Compared with the prior art, the steel for large power locomotive traction gear has the advantages that chemical components are adjusted, carbon content and nickel content are increased, the strength is ensured and simultaneously the plasticity is improved, sulfur content and phosphor content are adjusted simultaneously, the processing property is ensured, a novel material which has high strength and good plasticity and can be processed easily is formed, and the special requirement for the steel for large power locomotive traction gear is satisfied.

Description

Steel for large power locomotive traction gear

Technical field

The present invention relates to a kind of steel, particularly a kind of steel for large power locomotive traction gear.

Background technology

Along with the fast development of railway to the high-speed overload direction, need develop high-power, high-revolving railway locomotive, as 7200Kw, 9600Kw electric locomotive, and locomotive traction gear is the key part of locomotive, the modulus of gear is big, the load of bearing is big, requires to have very high bending strength and very high contact fatigue strength.

In order to satisfy the requirement of the high bending strength of gear, the hardening capacity of steel must be high, in order to satisfy the high contact fatigue strength of gear, requires steel to have very high infiltration layer hardening capacity, guarantee gear after carburizing, quenching, cementation zone can obtain the martensitic stucture more than 99%.The design of the hardening capacity of steel should guarantee that the heat treatment deformation of gear is little, to guarantee the correct engagement between the driving and driven gear.The broken teeth accident will take place in the bending strength (or centre hardness) after thermal treatment if the hardening capacity of steel can not guarantee gear.If the design of the composition of steel can not guarantee that the gear wheel carburization layer has very high hardening capacity, non-martensite microstructure will appear, and pit, case crush can appear in the flank of tooth.If distortion is big after the gear carburizing quenching, driving and driven toothing is bad, and noise is big, and the life-span is low.

At present, locomotive comprises 12CrNi3,20Cr2Ni4,20CrMnMo, 20CrNiMo etc. with the material of traction gear, and tensile strength generally can reach 800MPa.And require more than 1000MPa for tensile strength, existing material is difficult to reach.Can only select European standard EN10084 material 18CrNiMo7-6 or German standard DIN17200 material 17CrNiMo6 for use.But tensile strength also requires ballistic work more than 40J when requiring more than 1000MPa, also can't reach by above-mentioned Europe or German material mixture ratio at present.Be that existing material can not only satisfy high strength but also satisfy high-ductility, the manufacturing with traction gear makes troubles to locomotive.

Summary of the invention

The purpose of this invention is to provide a kind of tensile strength and reach more than the 1000MPa, ballistic work reaches the above steel for large power locomotive traction gear of 40J simultaneously, overcomes the deficiencies in the prior art.

Steel for large power locomotive traction gear of the present invention comprises following component and mass percent:

The title mass percent

Carbon 0.16%-0.21%

Chromium 1.50%-1.80%

Nickel 1.50%-1.70%

Silicon＜0.40%

Manganese 0.50%-0.90%

Sulphur＜0.020%

Phosphorus＜0.020%

Molybdenum 0.25%-0.35%

Iron surplus;

Wherein hydrogen richness is for being less than or equal to 2ppm; Oxygen level is for being less than or equal to≤20ppm.

Steel for large power locomotive traction gear of the present invention, compared with prior art chemical ingredients is wherein adjusted, carbon content, nickel content have been improved, in proof strength, improve plasticity, adjusted the content of sulphur, phosphorus simultaneously, guaranteed processing characteristics, it is good to have formed plasticity of high while of a kind of intensity, and the novel material that is easy to process satisfies the special requirement of steel for large power locomotive traction gear.

Embodiment

Embodiment 1: component and quality that locomotive traction gear of the present invention is drawn together with ladle are as follows:

Title quality (kilogram)

Carbon 0.16

Chromium 1.50

Nickel 1.50

Silicon 0.10

Manganese 0.50

Sulphur 0.010

Phosphorus 0.010

Molybdenum 0.25

Iron surplus;

Wherein hydrogen richness is 0.001 kilogram, and oxygen level is 0.0015 kilogram, and total mass is a double centner, and the purity of iron standard is routinely carried out.

Embodiment 2: component and quality that locomotive traction gear of the present invention is drawn together with ladle are as follows:

Title quality (kilogram)

Carbon 0.21

Chromium 1.80

Nickel 1.70

Silicon 0.40

Manganese 0.90

Sulphur 0.020

Phosphorus 0.020

Molybdenum 0.35

Iron surplus;

Wherein hydrogen richness is 0.0002 kilogram, and oxygen level is 0.002 kilogram, and total mass is a double centner, and the purity of iron standard is routinely carried out.

Embodiment 3: component and quality that locomotive traction gear of the present invention is drawn together with ladle are as follows:

Title quality (kilogram)

Carbon 0.18

Chromium 1.7

Nickel 1.6

Silicon 0.30

Manganese 0.7

Sulphur 0.015

Phosphorus 0.016

Molybdenum 0.30

Iron surplus;

Wherein hydrogen richness is 0.00015 kilogram, and oxygen level is 0.0016 kilogram, and total mass is a double centner, and the purity of iron standard is routinely carried out.

Claims (1)

1. steel for large power locomotive traction gear is characterized in that: comprise following component and mass percent:

The title mass percent

Carbon 0.16%-0.21%

Chromium 1.50%-1.80%

Nickel 1.50%-1.70%

Silicon＜0.40%

Manganese 0.50%-0.90%

Sulphur＜0.020%

Phosphorus＜0.020%

Molybdenum 0.25%-0.35%

Iron surplus;

Wherein hydrogen richness is for being less than or equal to 2ppm; Oxygen level is for being less than or equal to≤20ppm.