Production method of low-cost easily-welded steel

A production method and easy welding technology, applied in the field of metal rolling, can solve the problems of poor plasticity, deterioration of the structure, affecting the compactness of the weld, and achieve the effects of increasing the welding speed, optimizing the production process, and improving the welding performance.

Inactive Publication Date: 2013-08-21
HBIS COMPANY LIMITED HANDAN BRANCH COMPANY
View PDF7 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] At present, for thin-gauge medium-carbon steel cold-rolled preparations, welding porosity often occurs before acid rolling. Porosity is a common welding defect in laser-welded welds. It not only affects the compactness of the weld, but also significantly reduces the strength of the weld. , plasticity and toughness, especially unfavorable to the dynamic load strength. In the subsequent cold rolling process, there will be buckling and strip breakage, which will have a very serious impact on the quality of the strip steel, on-site production order, and work efficiency.
The thickness specification of medium-carbon strip steel that is not welded is usually below 3.5mm. The proportion of hard phase pearlite in the microstructure of the strip steel is high, the strength is high, the hardness is high, and the plasticity is poor. During the welding process, the structure deteriorates seriously, and the weld matrix Limited melting of metals, making welding difficult

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
  • Production method of low-cost easily-welded steel
  • Production method of low-cost easily-welded steel
  • Production method of low-cost easily-welded steel

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0043] Example 1: Purified molten steel is obtained through smelting, and then cast into slabs through a continuous casting machine. The composition weight percentages are: C: 0.183%, Si: ≤0.112%, Mn: 0.234%, P: ≤0.016% , S: ≤0.009%, Als: 0.0097%.

[0044] Heat the slab to 1181°C, keep it warm for 30 minutes, then turn on all the high-pressure water for descaling, and the pressure is 17.3Mpa; the slab after descaling is subjected to rough rolling for 3+3 times, and the temperature setting at the entrance of the finish rolling is 998°C , Open 3 groups of cooling water between racks. The temperature setting value of the finish rolling outlet is 862°C, the thickness range is 3.5-3.15mm, the laminar flow cooling method adopts the accelerated cooling mode, the strip cooling rate is increased by 5-7.9%, and the laminar flow cooling "water cooling section" cooling rate reaches 65- 78°C / s, laminar flow cooling "full stage" cooling rate is controlled at 12.65-15.65°C / s, coiling temper...

Embodiment 2

[0045] Example 2: Purified molten steel is obtained through smelting, and then cast into slabs through a continuous casting machine. The composition weight percentages are: C: 0.189%, Si: ≤0.104%, Mn: 0.241%, P: ≤0.012% , S: ≤0.008%, Als: 0.0010%.

[0046] Heat the slab to 1189°C, keep it warm for 25 minutes, then turn on all the high-pressure water for descaling, and the pressure is 17.6Mpa; the slab after descaling is subjected to rough rolling for 3+3 times, and the temperature setting at the entrance of the finish rolling is 992°C , Open 3 groups of cooling water between racks. The temperature setting value of the finish rolling exit is 867°C, the thickness range is 3.14-2.75mm, the laminar flow cooling method adopts the accelerated cooling mode, the strip cooling rate is increased by 5.8-8.3%, and the laminar flow cooling "water cooling section" cooling rate reaches 73- 87°C / s, the laminar flow cooling "full stage" cooling rate is controlled at 14.65-17.25°C / s, and the c...

Embodiment 3

[0047] Example 3: Purified molten steel is obtained by smelting, and then continuously cast into a slab through a continuous casting machine. The composition weight percentages are: C: 0.196%, Si: ≤0.092%, Mn: 0.256%, P: ≤0.010% , S: ≤0.0089%, Als: 0.011%.

[0048] Heat the slab to 1190°C, keep it warm for 22 minutes, then turn on all the high-pressure water for descaling, and the pressure is 18Mpa; the slab after descaling is subjected to rough rolling for 3+5 times, and the temperature at the entrance of the finish rolling is set at 985°C. The cooling water between the racks is opened to 4 groups. The temperature setting value of the finish rolling exit is 870°C, the thickness range is 2.75-2.25mm, the laminar flow cooling method adopts the accelerated cooling mode, the strip cooling rate is increased by 7-12.9%, and the laminar flow cooling "water cooling section" cooling rate reaches 81- 102°C / s, laminar flow cooling "full stage" cooling rate is controlled at 15.3-18.4°C / ...

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 relates to a production method of low-cost easily-welded steel and belongs to the technical field of metal rolling. According to the technical scheme, the production method is characterized in that alloy elements for improving the welding performance are not required to be added, the content of easily-welded soft-phase ferrites in the microstructure of hot rolling strip steel is controlled on line to account for 70%-95%, and the content of difficultly-welded hard-phase pearlites in the microstructure of the hot rolling strip steel is controlled on line to account for 5%-30%; and an accelerated cooling manner is adopted, the cooling rate is increased by 5-15% on the basis of the original cooling rate, after acceleration, the cooling rates of strip steel laminar cooling water-cooling sections with different thicknesses and sizes are controlled at 65-105 DEG C/s, and the cooling rate of laminar cooling in the whole stage is controlled at 12.56-19.4 DEG C/s, so that the nucleation rate of phase transformation is increased, and the grain growth slows down. According to the production method, the product with the mechanical property and the welding property which are well matched is obtained by controlling the microstructure of the hot rolling strip steel, and the welding quality of the strip steel and the labor productivity are improved; the optimization of alloy compositions is not required, the welding performance is improved by optimization of a production technology, the low-cost production is realized, and the market competitiveness of hot rolling products and cold rolling products is further increased.

Description

technical field [0001] The invention relates to a production method of low-cost easy-to-weld steel, which belongs to the technical field of metal rolling. Background technique [0002] At present, for thin-gauge medium-carbon steel cold-rolled preparations, welding porosity often occurs before acid rolling. Porosity is a common welding defect in laser-welded welds. It not only affects the compactness of the weld, but also significantly reduces the strength of the weld. , plasticity and toughness, especially for the dynamic load strength is more unfavorable, in the subsequent cold rolling process, there will be buckling and strip breakage, which will have a very serious impact on the quality of strip steel, on-site production order, and work efficiency. The thickness specification of medium-carbon strip steel that is not welded is usually below 3.5mm. The proportion of hard phase pearlite in the microstructure of the strip steel is high, the strength is high, the hardness is ...

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): C22C38/04C22C33/04C21D8/02
Inventor 彭兆丰许斌吝章国孙玉虎刘红艳李建文张志鸿朱建良杨志敏李金波范佳王静
Owner HBIS COMPANY LIMITED HANDAN BRANCH COMPANY
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