Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for increasing quenching degree and heat processing performance of gear steel

A technology of hardenability and thermal processing, which is applied in the field of improving the hardenability and thermal processing performance of gear steel, and can solve the problems of high hardenability of gear steel, low cost and high cost of gear steel

Inactive Publication Date: 2006-08-30
SHANXI TAIGANG STAINLESS STEEL CO LTD
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In order to overcome the shortcomings of existing methods for improving the hardenability and hot workability of gear steel, which are high in cost and easy to crack during hot work, the present invention provides a method for improving the hardenability and hot workability of gear steel , the cost of processing gear steel by this method is low, and the processed gear steel has good hardenability, high plasticity and toughness

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0015] Embodiment 1 is a method for improving the hardenability and hot workability of 40MnBH gear steel. The user requires that the end quenching performance is narrower and stricter than the relevant standard, and the requirement is the upper limit of the standard. The steps are as follows:

[0016] 1 electric furnace smelting

[0017] Electric furnace smelting is to complete the melting and oxidation of scrap steel. Add 30 tons of scrap steel to a 50-ton high-power electric furnace. The P content in the scrap steel is generally 0.020-0.035%, which is 0.026% in this embodiment; Added to the same high-power electric furnace, the P content in the molten iron is generally 0.040-0.070%, which is 0.055% in this embodiment, and the Si content is generally 0.5-0.8%, which is 0.6% in this embodiment; start oxygen blowing after adding molten iron, The whole process of oxygen-blowing scrap steel melting and molten steel oxidation is carried out at the same time. During the smelting pr...

Embodiment 2

[0020] Embodiment two is the method for improving the hardenability and hot workability of 20CrMnTiH gear steel. This steel type is used to manufacture gears and main shafts of automobiles and heavy lathes, requiring good hardenability and surface quality. The steps are as follows:

[0021] 1 electric furnace smelting

[0022] Add 33 tons of scrap steel into a 50-ton high-power electric furnace. The P content in the scrap steel is generally 0.020-0.035%, which is 0.030% in this embodiment; The P content is 0.040-0.070%, which is 0.060% in this embodiment, and the Si content is generally 0.5-0.8%, which is 0.6% in this embodiment; oxygen blowing is started after adding molten iron, and the whole process of oxygen blowing is used to melt scrap steel and oxidize molten steel at the same time During the smelting process, solid furnace materials such as scrap steel and lime are rapidly melted, and C, P, gas, and inclusions are removed at the same time. Generally, the temperature of...

Embodiment 3

[0025] Embodiment three is the method for improving the hardenability and hot workability of ZL20CrMoH gear steel. This steel type is used for rear axle gears and transmission gears of 8-ton trucks. Austenite grain size requirements are very strict, the steps are as follows:

[0026] 1 electric furnace smelting

[0027]Add 30 tons of scrap steel into a 50-ton high-power electric furnace. The P content in the scrap steel is generally 0.020-0.035%, which is 0.025% in this embodiment; The P content is generally 0.040-0.070%, and this embodiment is 0.050%, and the Si content is generally 0.5-0.8%, and this embodiment is 0.6%. During the smelting process, scrap steel and lime solids are rapidly melted, and C, P, gas, and inclusions are removed at the same time. Generally, the temperature of molten steel reaches 1640-1680°C, C≥0.09%, and P≤0.017%. Present embodiment is at 1660 DEG C, C=0.12%, when P=0.016%, the molten steel is poured into ferrochromium, ferromanganese, ferromolybd...

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

No PUM Login to View More

Abstract

The method of raising the quenching degree and heat processing performance of gear steel includes controlling the P content in molten steel during electric furnace smelting to not more than 0.017 wt%, adding P-Fe alloy during refining in refinery furnace to P content in steel product of 0.018-0.026 wt%, and making the steel product possess relatively low alloy element content of standard gear steel. The said method can raise the quenching degree and heat processing performance of gear steel effectively.

Description

technical field [0001] The invention relates to a method for improving the hardenability and hot working performance of gear steel. Background technique [0002] With the development of machinery manufacturing industry, the quality requirements of gear steel are getting higher and higher. High-grade gear steel requires both a narrow high hardenability zone and good hot workability. [0003] Among the many factors affecting the hardenability of gear steel, the influence of chemical composition is the most important. For hypoeutectoid steel, that is, steel with C<0.77%, the hardenability of steel increases significantly with the increase of C, Mn, and Cr content. . The existing methods for improving the hardenability and hot workability of gears generally ensure that the hardenability of gear steel is qualified by controlling the contents of C, Mn, and Cr in the steel. In order to improve the hardenability of gear steel, the addition of C, Mn, and Cr alloy elements shoul...

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 Patents(China)
IPC IPC(8): C22C33/04C21C7/00
Inventor 段建平杜丽娜郝旭明李学超
Owner SHANXI TAIGANG STAINLESS STEEL CO LTD