Method for adding rare earth metal into steel to improve performance

A rare earth metal and performance technology, applied in the field of high-quality metal material manufacturing, can solve the problems of large inclusion aggregation, nozzle nodules, and rare earth elements cannot play a sustainable and stable role, avoiding the generation of large-sized inclusions and increasing the uniformity. , the effect of improving the flexibility of process operation

Active Publication Date: 2017-03-22
INST OF METAL RESEARCH - CHINESE ACAD OF SCI
View PDF13 Cites 42 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is: rare earth elements cannot play a continuous and stable role in steel, resulting in the technical problems of large-scale inclusion accumulation and nozzle nodulation

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 adding rare earth metal into steel to improve performance
  • Method for adding rare earth metal into steel to improve performance
  • Method for adding rare earth metal into steel to improve performance

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0069] Example 1 - alloy dual phase steel

[0070] Material: DP600;

[0071] Molten steel weight: 100 tons (t) / furnace × 15 furnaces;

[0072] Production process: EAF-LF-VD-CC;

[0073] Purity of molten steel before adding rare earth metals: oxygen content is 32ppm, sulfur content is 74ppm;

[0074] Timing of adding rare earth metals: after VD;

[0075] Rare earth metal addition: 40kg (0.4kg / t steel);

[0076] Rare earth metal purity: total oxygen content 85ppm;

[0077] The rare earth metal is lanthanum-cerium mixed rare earth, and the weight ratio of lanthanum to cerium is 1:2;

[0078] Billet specification: 250mm×1600mm continuous casting slab;

[0079] Steel product specifications: 3.5mm×1600mm rolled plate;

[0080] In this embodiment, the process of continuous casting was produced for 15 hours, and the process went smoothly. The impact performance of the finished plate of this embodiment is compared with that of the plate without rare earth metal treatment, such ...

Embodiment 2

[0085] Example 2 - high quality bearing steel

[0086] Material: GCr15;

[0087] Molten steel weight: 120t / furnace × 12 furnaces;

[0088] Production process: BOF-LF-RH-CC;

[0089] Purity of molten steel before adding rare earth metals: oxygen content is 10ppm, sulfur content is 30ppm;

[0090] Timing of adding rare earth metals: after RH;

[0091] Rare earth metal addition: 120kg (1.0kg / t steel);

[0092] Rare earth metal purity: total oxygen content 65ppm;

[0093] The rare earth metal is cerium;

[0094] Billet specification: Φ350mm continuous casting round billet;

[0095] Steel finished product specification: Φ50mm rolled bar;

[0096] The size of the inclusions is very important to the fatigue performance of the bearing steel. Table 1 shows the distribution ratio of the inclusions in different size ranges in Example 2 and its comparison with that of the bearing steel without adding rare earth. It can be seen that the large-size inclusions larger than 5 μm are elim...

Embodiment 3

[0107] Example 3 - stainless steel

[0108] Material: 410S;

[0109] Molten steel weight: 80t / furnace × 6 furnaces;

[0110] Production process: MFF-AOD-CC;

[0111] Purity of molten steel before adding rare earth metals: oxygen content is 25ppm, sulfur content is 40ppm;

[0112] Timing of adding rare earth metals: after AOD;

[0113] Rare earth metal addition: 12kg (0.15kg / t steel);

[0114] Rare earth metal purity: total oxygen content 80ppm;

[0115] The rare earth metal is lanthanum-cerium mixed rare earth, and the weight ratio of lanthanum to cerium is 1:2;

[0116] Billet specification: 200mm×1700mm continuous casting slab;

[0117] Specifications of finished steel products: 3mm×1800 rolled plates;

[0118] In this embodiment, continuous pouring can be realized for 6 hours, and production runs smoothly.

[0119] The size of the inclusions is an important index affecting the deep drawing performance of this type of stainless steel. Table 2 shows the comparison of ...

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
sizeaaaaaaaaaa
sizeaaaaaaaaaa
sizeaaaaaaaaaa
Login to view more

Abstract

The invention relates to the field of manufacturing of high-quality metal materials, in particular to a method for adding rare earth metal into steel to improve the performance. In the smelting process of molten steel, the degree of purity of the molten steel and the degree of purity of the high-purity rare earth metal are strictly controlled; the high-purity rare earth metal is added into a steel ladle; the content of sulfur in the molten steel is below 200 ppm and the total oxygen content is below 40 ppm before the high-purity rare earth metal is added; and the total oxygen content of the added high-purity rare earth metal is below 200 ppm. The method is applicable to the processes such as a converter BOF-ladle refining LF-vacuum degassing RH or VD-continuous casting CC / mold casting MC flow, an electric arc furnace EAF-ladle refining LF-vacuum degassing RH or VD-continuous casting CC / mold casting MC flow and a converter BOF / intermediate frequency furnace GOR / AOD(-ladle refining LF)-continuous casting CC / mold casting MC flow, prepares high-quality carbon structural steel, low alloy steel, medium-high alloy steel, tool and mould steel, bearing steel, spring steel, stainless steel and electrical steel, and solves the bottleneck problems that due to a conventional rare earth adding process, the performance of rolled steel is not stable and a water gap is blocked in the production process.

Description

technical field [0001] The invention relates to the field of high-quality metal material manufacturing, in particular to a method for adding high-purity rare earth metals to molten steel to further improve the performance of the steel. Background technique [0002] my country's research on the application of rare earth elements in steel began in the late 1950s. Research on the application of rare earth elements in steel has made some breakthroughs in theory and practice, and many achievements have been made in the application of rare earth elements in steel. A large number of research and production experience have shown that rare earth elements have an important impact on the structure and mechanical properties of steel and alloys. For example, rare earths have the effect of deep deoxidation and deep desulfurization. Rare earths can modify and refine inclusions. Rare earths can inhibit grain growth, thereby improving the toughness and plasticity, fatigue performance, wear ...

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): C22C33/04C21C7/00C21C7/072
CPCC21C7/0006C21C7/072C22C33/04
Inventor 栾义坤刘宏伟傅排先杨超云夏立军李殿中李依依
Owner INST OF METAL RESEARCH - CHINESE ACAD OF SCI
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