Strip-casting 550-MPa-level weathering resistant steel and production method thereof

A production method and technology of weathering steel, applied in the direction of metal rolling, etc., can solve the problems of long production process of thin gauge, segregation of slab center, poor welding performance, etc., to shorten the production process and process, reduce the number of hot rolling passes, The effect of improving welding performance

Pending Publication Date: 2019-06-14
SHAGANG GROUP +2
View PDF4 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] Aiming at the problems of slab center segregation, poor surface quality, long thin-gauge production process, high production cost, low production efficiency, difficult-to-control thin-gauge product shape and poor welding performance of the existing 550MPa grade weathering steel, the present invention Provided is a new type of weathering steel and its production method, the purpose of which is to shorten the production process of weathering steel, reduce production costs, improve the production efficiency of thin gauge weathering steel, improve the shape of thin gauge strip steel, and improve the welding performance of weathering steel

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
  • Strip-casting 550-MPa-level weathering resistant steel and production method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] This embodiment proceeds according to the following steps:

[0040] 1) Smelting

[0041] The chemical composition of molten steel is: C: 0.25%, Si: 0.40%, Mn: 0.55%, P: 0.06%, S: 0.002%, N: 0.003%, Cu: 0.70%, Cr: 0.60%, Ni: 0.04%, Nb: 0.15%, the rest is Fe and unavoidable impurities;

[0042] 2) Thin strip continuous casting

[0043] The molten steel qualified for smelting is continuously cast into a casting strip with a thickness of 1.9mm through a pair of counter-rotating copper casting rolls, and the superheating degree of the molten steel is 52°C;

[0044] 3) On-line hot rolling of cast strip

[0045] The reduction in hot rolling is 53%, and the temperature after strip rolling is 1020°C;

[0046] 4) Cooling and coiling

[0047] The hot-rolled strip is cooled to 580°C by air mist and coiled into coils.

[0048] The thin strip of weathering steel obtained through the above steps has a thickness of 0.9mm. The mechanical properties of the thin strip are tested, an...

Embodiment 2

[0050] This embodiment proceeds according to the following steps:

[0051] 1) Smelting

[0052] The chemical composition of molten steel is: C: 0.15%, Si: 0.38%, Mn: 0.40%, P: 0.04%, S: 0.002%, N: 0.002%, Cu: 1.20%, Cr: 0.80%, Ni: 0.07%, Nb: 0.08%, the rest is Fe and unavoidable impurities;

[0053] 2) Thin strip continuous casting

[0054] The molten steel qualified for smelting is continuously cast into a casting strip with a thickness of 2.4mm through a pair of counter-rotating copper casting rolls, and the superheating degree of the molten steel is 45°C;

[0055] 3) On-line hot rolling of cast strip

[0056] The reduction in hot rolling is 46%, and the temperature after strip rolling is 1030°C;

[0057] 4) Cooling and coiling

[0058] The hot-rolled strip is cooled to 520°C by air mist and coiled into coils.

[0059] The thin strip of weathering steel obtained through the above steps has a thickness of 1.3mm. The mechanical properties of the thin strip are tested, and ...

Embodiment 3

[0061] This embodiment proceeds according to the following steps:

[0062] 1) Smelting

[0063] The chemical composition of molten steel is: C: 0.20%, Si: 0.78%, Mn: 0.85%, P: 0.05%, S: 0.003%, N: 0.002%, Cu: 0.90%, Cr: 1.20%, Ni: 0.05%, Nb: 0.05%, the rest is Fe and unavoidable impurities;

[0064] 2) Thin strip continuous casting

[0065] The molten steel qualified for smelting is continuously cast into a casting strip with a thickness of 2.2mm through a pair of counter-rotating copper casting rolls, and the superheating degree of the molten steel is 38°C;

[0066] 3) On-line hot rolling of cast strip

[0067] The hot rolling reduction is 50%, and the temperature after strip rolling is 970°C;

[0068] 4) Cooling and coiling

[0069] The hot-rolled steel strip is cooled to 470°C by air mist and coiled into coils.

[0070] The thin strip of weathering steel obtained through the above steps has a thickness of 1.1mm. The mechanical performance test of the thin strip shows ...

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
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
widthaaaaaaaaaa
Login to view more

Abstract

The invention discloses strip-casting 550-MPa-level weathering resistant steel and a production method thereof. The method comprises the steps of 1), smelting: the chemical components of molten steelcomprises C lower than 0.03%, 0.20-0.80% of Si, Mn lower than 1.0%, 0.03-1.50% of P, S lower than or equal to 0.008%, N lower than or equal to 0.008%, 0.40-1.50% of Cu, 0.05-1.50% of Cr, Ni lower than0.10%, 0.05-0.20% of Nb and the balanced Fe and unavoidable impurities; 2), strip casting: continuous casting is conducted on molten steel on which qualified smelting is conducted by a pair of coppercasting rolls which are rotated in the same directions to produce a casting strip with the thickness of 1.4-2.5 mm, and the superheating of the molten steel is controlled to be lower than 80 DEG C; 3), casting strip online hot rolling: the hot rolling pressing amount is 15-65%, the temperature of pressed strip steel is 950-1050 DEG C; 4), cooling and winding: the temperature of strip steel on which hot rolling is conducted is cooled down to 450-600 DEG C through atomizing cooling to obtain fine and uniform ferrite and less amount of pearlite tissues. The 550-MPa-level weathering resistant steel has the advantages of short production procedure, low production cost, good strip steel shape and easy welding.

Description

technical field [0001] The invention belongs to the field of low-alloy high-strength steel manufacturing, and in particular relates to a low-cost, short-flow, easy-to-weld, high-weather-resistant, high-strength weather-resistant steel thin strip and a production method thereof. Background technique [0002] Weathering steel has the characteristics and significant advantages of green, environmental protection, and longevity. It is not only suitable for a variety of climates and environments, but also has high strength, high toughness, weldability, fire resistance, and wear resistance. It is widely used in the production of tanks , vehicles, buildings, bridges, pipelines, machinery and other industries. [0003] At present, most of the 550MPa grade weathering steel produced at home and abroad adopts Nb, V, Ti, Mo composite microalloying technology to improve the comprehensive mechanical properties of weathering steel through fine grain strengthening and precipitation strengthe...

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): C22C38/02C22C38/04C22C38/42C22C38/48B21B1/46
Inventor 李化龙陈爱华郭海荣施一新刘俭马毅刘玉君刘新院李霞吴荣洲
Owner SHAGANG GROUP
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