Method for reducing segregation during casting process of continuous-casting square billet for gear

A continuous casting and gear technology, applied in the field of alloy steel, can solve problems such as serious segregation, and achieve the effects of avoiding segregation aggregation, fully cooling, and reducing segregation

Active Publication Date: 2020-06-16
JIANGSU LIHUAI IRON AND STEEL CO LTD +1
View PDF14 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, too strong electromagnetic stirring will promote the solute exchange at the solidification front, resulting in serious segregation

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
  • Method for reducing segregation during casting process of continuous-casting square billet for gear
  • Method for reducing segregation during casting process of continuous-casting square billet for gear
  • Method for reducing segregation during casting process of continuous-casting square billet for gear

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] 1) When SAE8620H is smelted in the LF refining process, after the alloy element composition of the molten steel is adjusted to the target value in the mid-stage of refining, the electrode is energized to raise the temperature of the molten steel to the liquidus temperature +70°C for vacuum treatment;

[0029] 2) Continuous casting 150×150mm billet crystallizer uses 150m 3 / h water volume, turn off the electromagnetic stirrer of the crystallizer, the stirring parameters of the end electromagnetic stirrer are: 60A / 10Hz (alternate mode), the casting speed is 2.00m / min, the specific water volume of the secondary cooling is 0.60L / kg, and the water volume ratio of the foot roll section 40%;

[0030] 3) Use a Φ6mm alloy drill bit to sample the cuttings at 6 points from the surface, 10mm, 1 / 16L, 1 / 8R, 1 / 4L, 3 / 8L, 1 / 2L, on the diagonal line of the billet transverse low-magnification sample, And use the infrared carbon sulfur analyzer carbon content, after analysis, from the sur...

Embodiment 2

[0036] 1) When 20CrMnTiH3 / RT smelting is carried out in the LF refining process, after the alloy element composition of the molten steel is adjusted to the target value in the mid-stage of refining, the electrode is energized to raise the temperature of the molten steel to the liquidus temperature +70°C for vacuum treatment;

[0037] 2) Continuous casting 150×150mm billet crystallizer uses 150m3 / h water volume, turn off the electromagnetic stirrer of the crystallizer, the stirring parameters of the end electromagnetic stirrer are: 60A / 10Hz (alternate mode), the casting speed is 2.00m / min, the specific water volume of the secondary cooling is 0.60L / kg, and the water volume ratio of the foot roll section 40%;

[0038] 3) Use a Φ6mm alloy drill bit to sample the cuttings at 6 points from the surface, 10mm, 1 / 16L, 1 / 8R, 1 / 4L, 3 / 8L, 1 / 2L, on the diagonal line of the billet transverse low-magnification sample, And use the infrared carbon sulfur analyzer carbon content, after analys...

Embodiment 3

[0044] 1) When 22CrMoH is smelted in the LF refining process, after the alloy element composition of the molten steel is adjusted to the target value in the mid-stage of refining, the electrode is energized to raise the temperature of the molten steel to the liquidus temperature +70°C for vacuum treatment;

[0045] 2) Continuous casting 150×150mm billet crystallizer uses 150m 3 / h water volume, turn off the electromagnetic stirrer of the crystallizer, the stirring parameters of the end electromagnetic stirrer are: 60A / 10Hz (alternate mode), the casting speed is 2.00m / min, the specific water volume of the secondary cooling is 0.60L / kg, and the water volume ratio of the foot roll section 40%;

[0046] 3) Use a Φ6mm alloy drill bit to sample the cuttings at 6 points from the surface, 10mm, 1 / 16L, 1 / 8R, 1 / 4L, 3 / 8L, 1 / 2L, on the diagonal line of the billet transverse low-magnification sample, And use the infrared carbon sulfur analyzer carbon content, after analysis, from the surf...

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 invention discloses a method for reducing segregation during a casting process of a continuous-casting square billet for a gear. The method comprises the following steps: before the end of LF refining, the temperature of molten steel is increased to the continuous-casting molten steel overheating degree of 20-30 DEG C; a relatively large amount of water is utilized for primary cooling and secondary cooling of the continuous-casting square billet of 150x150 mm; the proportion of the water volume of a foot roller section reaches 40%; the electromagnetic stirring function of a crystallizer isdisabled; the electromagnetic stirring at the tail end is performed at a relatively low electric current; and the casting is performed at a withdrawing speed of 2.00 m/min. According to the method, the electromagnetic stirring function of the crystallizer is disabled, and thus the circumstance that the molten steel purity is influenced when entrapped slag is generated due to excessive stirring inthe crystallizer during the molten steel casting process can be avoided; the cooling water volume can be increased, the cooling strength can be improved, the withdrawing speed can be reduced, and thecasting billet can be sufficiently cooled, the effects that the growth of columnar crystals is promoted and the central equiaxed crystal ratio is reduced can be achieved, the aggregation of solute elements towards the space among the crystals and the center can be avoided, and then the segregation of elements in the casting billet can be reduced; the carbon range from the surface to 3/8 of a diagonal of the continuous-casting square billet for the gear can be controlled to be within 0.015%; the central carbon segregation index can be within 1.05; and the steel performance stability can be improved.

Description

technical field [0001] The invention belongs to the technical field of alloy steel, and relates to the production of continuous casting billets for gears, in particular to a method for reducing segregation during pouring of continuous casting billets for gears. Background technique [0002] Gear steel is mainly used in transmission parts of automobiles, engineering machinery and machinery manufacturing industry. It not only has good strength, toughness, wear resistance, and can well withstand impact, bending and contact stress, but also requires small deformation, high precision and Low noise. High-quality gear steel meets the four quality indicators of narrow hardenability bandwidth, high purity, fine and uniform grains, and good surface quality. [0003] During the continuous casting process, the movement state of the molten steel at the end of solidification of the slab is an important factor affecting the internal quality of the slab. Due to dendrite bridging, insuffic...

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): B22D11/18B22D11/22
CPCB22D11/18B22D11/182B22D11/22
Inventor 林鹏张洪才郑力宁翟万里印传磊许正周
Owner JIANGSU LIHUAI IRON AND 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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap