Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

400-MPa-grade fine-grain hot rolled steel bar and manufacturing process thereof

A production process, 400mpa technology, applied in the field of hot-rolled steel bar production, can solve the problems of difficult production of precious alloy elements, and achieve the effects of sustainable development, increased strength, and improved overall performance

Active Publication Date: 2019-07-23
NORTHEASTERN UNIV
View PDF9 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method solves the problems of adding a large amount of precious alloy elements or the difficulty of controlled rolling production in the current production of steel bars, and realizes the refinement of steel bar grain size and the improvement of strength under the conditions of reducing alloy costs and simplifying the rolling process.

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
  • 400-MPa-grade fine-grain hot rolled steel bar and manufacturing process thereof
  • 400-MPa-grade fine-grain hot rolled steel bar and manufacturing process thereof
  • 400-MPa-grade fine-grain hot rolled steel bar and manufacturing process thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0060] A 400MPa-grade fine-grained hot-rolled steel bar, the chemical composition and the mass fraction of each chemical composition and the relational expressions satisfied by each element are shown in Table 1. The number of inclusions is shown in Table 2.

[0061] A production process of 400MPa grade fine grain hot-rolled steel bar, comprising the following steps:

[0062] (1) The molten iron is smelted into molten steel in a converter, the tapping temperature is 1665°C, the carbon mass fraction is 0.15%, the oxygen mass fraction is 0.035%, the phosphorus mass fraction is 0.04%, and the sulfur mass fraction is 0.03%. Add silicon and manganese in the process of / 3~3 / 4, according to the chemical composition of 400MPa fine-grained hot-rolled steel bar, adjust the C, Si, Mn element composition of molten steel after tapping;

[0063] (2) Continuous casting is carried out after the molten steel reaches the dissolved oxygen mass fraction of 0.005% and the total oxygen mass fractio...

Embodiment 2

[0068] A 400MPa-grade fine-grained hot-rolled steel bar, the chemical composition and the mass fraction of each chemical composition and the relational expressions satisfied by each element are shown in Table 1. The number of inclusions is shown in Table 2.

[0069] A production process of 400MPa grade fine grain hot-rolled steel bar, comprising the following steps:

[0070] (1) The molten iron and scrap steel are smelted into molten steel in a converter, the tapping temperature is 1670°C, the carbon mass fraction is 0.13%, the oxygen mass fraction is 0.05%, the phosphorus mass fraction is 0.023%, and the sulfur mass fraction is 0.025%, and the tapping temperature is 0.13%. Silicon and manganese are added in the process of 1 / 3 to 3 / 4. According to the chemical composition of 400MPa fine-grained hot-rolled steel bars, the elements of C, Si and Mn in molten steel are adjusted after tapping;

[0071] (2) Continuous casting is carried out after the molten steel reaches the dissol...

Embodiment 3

[0075] A 400MPa-grade fine-grained hot-rolled steel bar, the chemical composition and the mass fraction of each chemical composition and the relational expressions satisfied by each element are shown in Table 1. The number of inclusions is shown in Table 2.

[0076] A production process of 400MPa grade fine grain hot-rolled steel bar, comprising the following steps:

[0077] (1) The molten iron and scrap steel are smelted into molten steel in an electric furnace, the tapping temperature is 1646°C, the carbon mass fraction is 0.12%, the oxygen mass fraction is 0.035%, the phosphorus mass fraction is 0.028%, and the sulfur mass fraction is 0.015%. Silicon and manganese are added in the process of 1 / 3 to 3 / 4. According to the chemical composition of 400MPa fine-grained hot-rolled steel bars, the elements of C, Si and Mn in molten steel are adjusted after tapping;

[0078](2) Continuous casting is carried out after the molten steel reaches a dissolved oxygen mass fraction of 0.00...

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
aspect ratioaaaaaaaaaa
diameteraaaaaaaaaa
yield strengthaaaaaaaaaa
Login to View More

Abstract

The invention discloses a 400-MPa-grade fine-grain hot rolled steel bar and a manufacturing process thereof, and belongs to the field of hot-rolled steel bar production. The steel bar comprises the following components in percentage by mass: 0.20-0.25% of C, 0.3-0.8% of Si, 1.2-1.6% of Mn, 0.01-0.04% of P, 0.01-0.04% of S, 0.005-0.03% of Ti, 0.001-0.08 % of Cr, 0.0001-0.008% of V, 0.0001-0.008% ofNb, 0.0001-0.008% of Al, 0.01-0.02% of O, 0.003-0.01% of N, and the balance Fe and inevitable impurities; and the steel bar further comprises manganese silicate inclusions, titanium oxide manganese sulfide multiphase inclusions, manganese sulfide inclusions, and other inevitable inclusions. The manufacturing process comprises the following steps of smelting molten steel, heating a continuous casting billet, and rolling a steel bar. According to the process, by combining optimization of the components and the inclusions with smelting continuous casting and rolling improvement as well as the inclusion induced fine grain strengthening mechanism, the strength of the steel bar is improved, the addition of precious alloy elements is reduced, and low-cost and high-quality production of the hot-rolled steel bar is achieved.

Description

technical field [0001] The invention belongs to the technical field of hot-rolled steel bar production, and particularly relates to a 400MPa-grade fine-grain hot-rolled steel bar and a production process thereof. Background technique [0002] With the rapid development of my country's industrialization and urbanization, the demand for high-quality construction steel in the fields of infrastructure construction and construction has increased significantly. In order to further improve the quality of construction steel, promote energy conservation and emission reduction, eliminate outdated production capacity, and meet the needs of construction, transportation, engineering and other fields, my country began to implement a new national standard for hot-rolled ribbed steel bars GB / T 1499.2-2018. The new standard puts forward new requirements for rebar production process, metallographic structure and strength level. At present, improving the strength of steel bars is mainly achi...

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): C22C38/02C22C38/04C22C38/06C22C38/24C22C38/26C22C38/28C22C38/38C21D8/08C22C33/04
CPCC21D8/065C21D8/08C22C33/04C22C38/001C22C38/002C22C38/02C22C38/04C22C38/06C22C38/24C22C38/26C22C38/28C22C38/38Y02P10/20
Inventor 袁国王超康健李振垒王国栋
Owner NORTHEASTERN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com