Heat treatment method for performance uniformity of whole plate surface of 550 MPa grade steel plate

A heat treatment method and uniformity technology, applied in the field of metallurgy, can solve the problems of inability to heat treat the quenching machine, etc., and achieve the effect of improving the comprehensive performance and welding performance, high Z-direction area reduction rate, and performance uniformity

Inactive Publication Date: 2019-01-11
WUYANG IRON & STEEL
View PDF3 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Due to the single weight and size of the 550Mpa steel plate with large thickness and single weight, heat treatment cannot be performed in the quenching machine, and heat treatment is performed in the bottom heating furnace. Due to the heat treatment furnace type, the uniformity of the steel plate is not as uniform as that of the steel plate that is heat treated in the quenching machine. Therefore, the traditional heat treatment process cannot meet the technical requirements of the steel plate. It is necessary to study and control the structure of the steel plate during the heat treatment process, so as to achieve good strength and toughness matching of the steel plate and to meet the performance uniformity of the entire plate surface, especially the whole plate. Uniformity of Low Temperature Impact Toughness of Board Surface

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

[0020] In this example, the 550MPa grade steel plate has a thickness of 200mm, a width of 2500mm, and a unit weight of 31t; the steel plate and ingot are finished, and the chemical composition and mass percentage are: C: 0.14%, Si: 0.40%, Mn: 1.00%, Ni: 1.20% , P: 0.010%, S: 0.005%, Nb: 0.020%, V: 0.050%, Cr: 0.30%, Mo: 0.50%, Al: 0.020%, and the balance is Fe and unavoidable impurities.

[0021] In this example, the heat treatment for the performance uniformity of the entire plate surface of the 550MPa grade steel plate is carried out in a car bottom heating furnace, and the secondary quenching + tempering process is adopted. The heat treatment method includes heating, first quenching, second quenching, and tempering processes , the specific process steps are as follows:

[0022] (1) Heating process: the furnace temperature of the steel plate is 380°C, the heating and cooling rate is 85°C / h, and the single-layer steel loading method is adopted;

[0023] (2) The first quenchi...

Embodiment 2

[0028] In this example, the 550MPa steel plate has a thickness of 250mm, a width of 2650mm, and a unit weight of 32.5t; the steel plate and ingot are finished, and the chemical composition and mass percentage are: C: 0.17%, Si: 0.20%, Mn: 1.20%, Ni: 1.00 %, P: 0.005%, S: 0.003%, Nb: 0.040%, V: 0.035%, Cr: 0.50%, Mo: 0.40%, Al: 0.040%, and the balance is Fe and unavoidable impurities.

[0029] In this example, the heat treatment for the performance uniformity of the entire plate surface of the 550MPa grade steel plate is carried out in a car bottom heating furnace, and the secondary quenching + tempering process is adopted. The heat treatment method includes heating, first quenching, second quenching, and tempering processes , the specific process steps are as follows:

[0030] (1) Heating process: the furnace temperature of the steel plate is 385°C, the heating and cooling rate is 90°C / h, and the single-layer steel loading method is adopted;

[0031] (2) The first quenching p...

Embodiment 3

[0036] In this example, the 550MPa steel plate has a thickness of 220mm, a width of 2600mm, and a unit weight of 32.9t; the steel plate and ingot are finished, and the chemical composition and mass percentage are: C: 0.15%, Si: 0.25%, Mn: 1.05%, Ni: 1.15 %, P: 0.008%, S: 0.004%, Nb: 0.030%, V: 0.040%, Cr: 0.35%, Mo: 0.45%, Al: 0.035%, and the balance is Fe and unavoidable impurities.

[0037] In this example, the heat treatment for the performance uniformity of the entire plate surface of the 550MPa grade steel plate is carried out in a car bottom heating furnace, and the secondary quenching + tempering process is adopted. The heat treatment method includes heating, first quenching, second quenching, and tempering processes , the specific process steps are as follows:

[0038](1) Heating process: the furnace temperature of the steel plate is 400°C, the heating and cooling rate is 85°C / h, and the single-layer steel loading method is adopted;

[0039] (2) The first quenching pr...

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
widthaaaaaaaaaa
yield strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a heat treatment method for the performance uniformity of the whole plate surface of a 550 MPa grade steel plate. According to the heat treatment method, secondary quenching and tempering process heat treatment are adopted by a car bottom type heating furnace, and the heat treatment method comprises heating, primary quenching, secondary quenching and tempering processes. The heat treatment method solves the problem that the large-thickness large-single-weight steel plates cannot be normalized and quickly cooled in a roller type quenching furnace and the problem of the performance uniformity of the whole plate surface during heat treatment in the car bottom type heating furnace. A steel plate obtained after heat treatment has the characteristics that the steel platehas good mechanical properties, 1 / 4 thickness and 1 / 2 thickness positions of the steel plate are large in -20 DEG C impact energy and Z-direction section shrinkage rate, and the steel plate has a goodsingle bainite structure, excellent comprehensive performance and excellent welding performance. Meanwhile, the problem of the performance uniformity of the whole plate surface of the steel plate iseffectively improved, and the produced large-thickness large-single-weight 550 MPa grade steel plate has stable quality. The heat treatment method is especially suitable for the heat treatment processof the large-thickness large-single-weight 550 MPa grade steel plate.

Description

technical field [0001] The invention belongs to the technical field of metallurgy, and in particular relates to a heat treatment method for uniform performance of the entire plate surface of a 550MPa steel plate. Background technique [0002] In recent years, with the rapid development of hydropower construction, the demand for large-thickness steel plates has become increasingly prominent, and the market demand for steel for low-temperature pressure vessels with thick specifications is increasing. [0003] For a long time, due to the lack of necessary production equipment and technical support, and due to the poor mechanical properties of domestic steel with large thickness, large unit weight, and higher strength, such as negative temperature impact toughness, and high production costs, it cannot meet the needs of the domestic market. . Large-thickness steel plates for hydropower often rely on forging, which seriously restricts the development of my country's hydropower st...

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): C21D6/00C22C38/02C22C38/04C22C38/06C22C38/24C22C38/26C22C38/22
Inventor 邓建军莫德敏李杰龙杰庞辉勇张俊凯邹俊张晨光
Owner WUYANG IRON & STEEL
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