Method for smelting boron steel directly from pig iron containing boron

A technology of boron pig iron and boron steel, which is applied in the field of iron and steel smelting, can solve the problems of the uniformity of boron yield distribution and the difficulty of maintaining stable steel properties, and achieve the effects of eliminating cumbersome procedures, stable performance, and uniform distribution

Inactive Publication Date: 2007-01-24
NORTHEASTERN UNIV
View PDF6 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This smelting method not only requires the pre-preparation of ferroboron and composite ferroboron alloys, but also due to operational reasons, the yield of boron, the uniformity of boron dis

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
  • Method for smelting boron steel directly from pig iron containing boron
  • Method for smelting boron steel directly from pig iron containing boron

Examples

Experimental program
Comparison scheme
Effect test

Example

[0016] Example 1: Take 1000 g of boron-containing pig iron produced by blast furnace, add 15 g of calcium carbide-based desulfurizer for desulfurization, and obtain pre-treated desulfurized boron-containing pig iron. Take the above-mentioned desulfurized boron-containing pig iron 700g, its weight % content: B: 0.31, Si: 2.15, C: 3.88, P: 0.06, S: 0.05, Mn: 0.09 and scrap steel 300g, put it into a corundum crucible, and heat it in a medium frequency induction furnace , when the temperature reaches 1400 ℃, power outage, continue to maintain the molten pool temperature at 1400 ℃, add 140g of slag-forming agent, of which CaO120g, iron oxide scale 10g, MgO10g. Blow oxygen to the liquid surface of the molten pool, its strength is 2.5Nl / Kg·min, the oxygen blowing time is 20min, stop blowing, add 10g of manganese ferroalloy, the Mn content is 75-80%, the tapping temperature is controlled to 1560 ℃, and the boron steel is obtained. product. Sampling analysis results Weight % content: ...

Example

[0017] Example 2: Take 1000 g of boron-containing pig iron produced by a blast furnace, add 13 g of CaO and 2 g of sodium carbonate for desulfurization, and obtain pretreated boron-containing pig iron. Take the above-mentioned desulfurized boron-containing pig iron 600g, its weight % content: B: 0.45, Si: 2.52, C: 3.53, P: 0.06, S: 0.05, Mn: 0.10 and scrap steel 400g, put it into a corundum crucible, and heat it in an intermediate frequency induction furnace , when the temperature reaches 1400 ℃, the power is cut off, and the temperature of the molten pool is maintained at 1400 ℃, and 150g of slagging agent is added, including 130g of CaO and 20g of iron oxide scale. Then, oxygen was blown into the molten pool with an intensity of 3.0 Nl / Kg·min, and the oxygen blowing time was 23 minutes, and the blowing was stopped. Finally, 10 g of ferromanganese alloy is added, the Mn content is 75-80%, and the tapping temperature is controlled at 1570° C. to obtain a boron steel product. ...

Example

[0018] Example 3: Take 1000 g of boron-containing pig iron produced by blast furnace, add CaO2g and 13 g of calcium carbide desulfurizer, and carry out desulfurization to obtain pretreated boron-containing pig iron. Take 500g of the above-mentioned desulfurized boron-containing pig iron, and its weight % content is: B: 0.59, Si: 2.70, C: 3.10, P: 0.06, S: 0.05, Mn: 0.12, 400g of scrap steel and 100g of iron concentrate, put into corundum crucible , The medium frequency induction furnace is used for heating. When the temperature reaches 1400 ℃, the power is cut off, and the temperature of the molten pool is maintained at 1400 ℃. 150g of slag-forming agent is added, including 130g of CaO and 20g of iron oxide scale. Then, oxygen was blown into the molten pool with an intensity of 3.5Nl / Kg·min, and the oxygen blowing time was 25min, and the blowing was stopped. Finally, 10 g of ferromanganese alloy containing Mn 75-80% is added, and the tapping temperature is controlled to 1580° ...

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

This invention relates to prodn. of boron steel by using boron pig iron as raw material. The boron-contg. pig iron, produced from blast-furnace from boron iron ore, is used as raw material, proceeding sulphur-removing by using calcium carbonate, lime or calcium carbide or their composition as sulphur-removing agent, then feeding in a convertor. The prodn. procedure are as follows: (1). charging the above-said molten iron of 50-70% wt. parts and the rest being waste steel or iron ore, (2). adding slag-formation agent contg. CaO and small amount of iron scale and MgO at temp. of 1400 deg.C and maintanied at 1400 deg.C, (3). feeding-in oxygen for 20-25 min, with the feeding rate of 2.5-3.5 NM3/t.min and (4). finishing point control; steel-tapping temp. is 1550-1580 deg.C, and adding manganese iron alloy or silicon manganese alloy, to make the content of manganese being not less than 0.6% and the content of boron being of 0.001-0.006% (wt). Advantages are: even distribution of boron, stable steel properties.

Description

technical field [0001] The invention relates to a steel smelting method, in particular to a method for directly smelting boron steel with boron-containing pig iron. Background technique [0002] Boron can improve the hardenability of steel. The traditional boron steel smelting method was first invented and used in production in the United States in 1937. It is mainly the method of blast furnace smelting molten iron, molten iron steelmaking, and adding boron alloy in the later stage of steelmaking. Since boron has a strong binding force with oxygen and nitrogen, it is easy to form boron oxides and nitrides and lose its effect. In order to protect boron, it is necessary to add aluminum to fully deoxidize, and to add titanium, zirconium, etc. to fully fix nitrogen. There are two ways to add boron in the traditional smelting method: one is to add boron, aluminum, titanium, etc. separately, that is, first add aluminum to deoxidize, then add titanium to fix nitrogen, and finally ...

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
IPC IPC(8): C22C33/04C21C5/28
Inventor 刘素兰杨中东薛向欣樊占国李刚
Owner NORTHEASTERN UNIV
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