Vanadium-chromium microalloying large-specification 500MPa ultra-fine grain corrosion-resisting anti-seismic steel bar and preparation method thereof

A technology of micro-alloying and anti-seismic steel bars, which is applied in the field of metallurgy, can solve the problems of reducing product market competitiveness, high price of vanadium alloys, unfavorable production costs, etc., to improve anti-seismic performance, improve precipitation strengthening effect, and promote tensile strength Effect

Active Publication Date: 2020-08-11
WUKUN STEEL
View PDF6 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] At present, the domestic production technology for 500MPa high-strength seismic steel bars after the implementation of the GB / T 1499.2-2018 standard mainly adopts the vanadium nitrogen microalloying process, and the V content in the steel is controlled to ≥0.085wt%. The Vickers hardness and microstructure of the 500MPa high-strength steel bar meet the GB / T 1499.2-2018 standard, and the ferrite grain size of the steel bar microstructure is controlled at 9.5-11.0. However, the vanadium alloy is expensive, resulting in high production costs, which is not conducive to Reduction of production cost of steel bar enterprises and improvement of product market competitiveness
At present, there are no related patents and paper research reports on the preparation method of chrome-vanadium microalloying large-scale 500MPa ultra-fine grain anti-corrosion and anti-seismic steel bars in China.

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
  • Vanadium-chromium microalloying large-specification 500MPa ultra-fine grain corrosion-resisting anti-seismic steel bar and preparation method thereof
  • Vanadium-chromium microalloying large-specification 500MPa ultra-fine grain corrosion-resisting anti-seismic steel bar and preparation method thereof
  • Vanadium-chromium microalloying large-specification 500MPa ultra-fine grain corrosion-resisting anti-seismic steel bar and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0021] The method for preparing vanadium-chromium microalloyed large-size 500MPa ultra-fine-grain corrosion-resistant and shock-resistant steel bar of the present invention includes molten steel smelting, deoxidation alloying, LF furnace refining, casting, billet heating, and controlled rolling and controlled cooling, specifically including the following steps :

[0022] a. Molten steel smelting: scrap steel, pig iron and molten iron at 160-180kg / t respectively 钢 , 30~40kg / t 钢 , 850~880kg / t 钢 Ratio, add LD converter, then carry out conventional top-bottom compound blowing, add conventional lime, light-burned dolomite, magnesite ball slag, lime addition is 20-25kg / t 钢 , the amount of lightly burned dolomite added is 15-18kg / t 钢 , the addition of magnesite balls is 0.5kg / t 钢 , the carbon content at the control end point is ≥0.07wt%, the tapping temperature is ≤1625°C; the ladle before tapping is 4.0kg / t 钢 The amount of vanadium-containing pig iron in the following mass rati...

Embodiment 1

[0042] a. Molten steel smelting: 160kg / t respectively 钢 、30kg / t 钢 The cold material is charged into the proportion, and the scrap steel (chemical composition: C 0.20wt%, Si 0.35wt%, Mn 1.25wt%, P 0.032wt%, S 0.028wt% is added in the LD converter, and the rest is Fe and Inevitable impurities) and pig iron (chemical composition: C 3.2wt%, Si 0.20wt%, Mn 0.40wt%, P0.080wt%, S 0.020wt%, the rest is Fe and unavoidable impurities); Then press 880kg / t 钢The proportion of molten iron is loaded into the LD converter with the following temperature and mass ratio of molten iron: molten iron temperature 1290 ° C, molten iron composition C 4.2wt%, Si0.25wt%, Mn 0.40wt%, P 0.085wt%, S 0.025wt% , the rest is Fe and unavoidable impurities; scrap steel, pig iron and molten iron are blended into the LD converter, then conventional top-bottom composite blowing is carried out, and conventional lime, lightly burned dolomite and magnesite balls are added to make slag, and the amount of lime added ...

Embodiment 2

[0056] a. Molten steel smelting: 170kg / t respectively 钢 、40kg / t 钢 The cold material is loaded into the proportion, and the scrap steel (chemical composition: C 0.22wt%, Si 0.48wt%, Mn 1.32wt%, P 0.040wt%, S 0.039wt% is added to the LD converter with the following mass ratio, and the rest is Fe and Inevitable impurities) and pig iron (chemical composition: C 3.3wt%, Si 0.30wt%, Mn 0.50wt%, P0.090wt%, S 0.029wt%, the rest is Fe and unavoidable impurities); Then press 870kg / t 钢 The proportion of molten iron is loaded into the LD converter with the following temperature and mass ratio of molten iron: molten iron temperature 1300 ° C, molten iron composition C 4.4wt%, Si0.35wt%, Mn 0.55wt%, P 0.095wt%, S 0.035wt% , the rest is Fe and unavoidable impurities; scrap steel, pig iron and molten iron are blended into the LD converter, then conventional top-bottom composite blowing is carried out, and conventional lime, lightly burned dolomite and magnesite balls are added to make slag,...

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
diameteraaaaaaaaaa
diameteraaaaaaaaaa
Vickers hardnessaaaaaaaaaa
Login to view more

Abstract

The invention discloses a vanadium-chromium microalloying large-specification 500MPa ultra-fine grain corrosion-resisting anti-seismic steel bar and a preparation method thereof. The steel bar comprises, by weight percent, 0.21-0.25wt% of C, 0.45-0.55wt% of Si, 1.25-1.40wt% of Mn, 0.30-0.35wt% of Cr, 0.065-0.080wt% of V, not larger than 0.040wt% of S, not larger than 0.045wt% of P, not larger than0.0070wt% of O, 0.0165-0.0200wt% of N and the balance Fe and inevitable impurities. The preparation method of the steel bar comprises the procedures of molten steel smelting, deoxidization alloying,LF furnace refining, casting, steel blank heating and controlled rolling and controlled cooling. A certain amount of vanadium-containing pig iron is added into a tapping steel ladle to replace the expensive vanadium alloy, the V content of molten steel is increased, and the adding quantity of the vanadium alloy is reduced; in the deoxidization alloying process, a small quantity of silicon-nitrogenalloy is added, the nitrogen content in the molten steel is increased, and the proportion value of V / N in the steel is reduced, transferring of V from the solid solution state to a carbonitride precipitated phase in the rolling process is promoted, and the precipitation strength effect of the steel is obviously improved; and the preparation method is low in production cost and high in process applicability and controllability.

Description

technical field [0001] The invention belongs to the technical field of metallurgy, and in particular relates to a vanadium-chromium microalloyed large-scale 500MPa ultrafine-grain corrosion-resistant and shock-resistant steel bar and a preparation method thereof. Background technique [0002] Hot-rolled ribbed steel bar is the main reinforcement material of reinforced concrete building structure, and it carries the stress and strain of loads such as tensile and compressive stress and strain in the structure. At present, the annual output of hot-rolled ribbed steel bars in my country is about 200 million tons, which is the most widely used steel material in the construction of national economic construction projects. With the continuous development of my country's buildings towards high-rise, long-span and earthquake-resistant structures, the development of fine-grained anti-seismic steel bars with high strength, toughness and excellent comprehensive performance has become on...

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): C22C38/02C22C38/04C22C38/24C22C33/06C21C7/06C21D8/08
CPCC21C7/06C21D8/08C21D2211/002C21D2211/005C21D2211/009C22C33/06C22C38/02C22C38/04C22C38/12Y02P10/20
Inventor 陈伟赵宇张卫强李金柱吴光耀曹重邓家木苏灿东刘林刚刘红兵赵亮
Owner WUKUN 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