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

Strengthening-toughening treatment process for high-strength martensite/ferrite dual-phase steel, and dual-phase steel

A treatment process and ferrite technology, applied in the field of steel processing, can solve the problems of unfavorable plasticity increase, inability to obtain high strength, reduction and other problems, and achieve the effect of improving strength and toughness

Inactive Publication Date: 2019-11-01
XIJING UNIV
View PDF4 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, when the grains are further refined, the n value (strain hardening index) will decrease, which is not conducive to the improvement of plasticity, and even leads to the problem of decreased plasticity and increased brittleness, and cannot obtain high strength and toughness properties

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
  • Strengthening-toughening treatment process for high-strength martensite/ferrite dual-phase steel, and dual-phase steel
  • Strengthening-toughening treatment process for high-strength martensite/ferrite dual-phase steel, and dual-phase steel
  • Strengthening-toughening treatment process for high-strength martensite/ferrite dual-phase steel, and dual-phase steel

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0038] A high-strength martensitic / ferritic dual-phase steel strengthening and toughening treatment process, the material is 15Mn2Si2Cr1Mo, the weight is 16Kg, and the main components are C: 0.15%, Mn: 2.3%, Si: 1.5%, Cr: 1%, Also contains a small amount of Mo (<0.5%).

[0039] The specific process is: (1) high-temperature homogenization treatment: the steel ingot is heated to 1150°C in an atmosphere protection furnace, and held for 60 minutes for high-temperature homogenization treatment to obtain a single-phase austenite structure; (2) high-temperature forging: the steel ingot is heated by an atmosphere Take it out of the protective furnace, and immediately carry out high-temperature forging. The final forging temperature is about 920°C, and the forging ratio is about 85%; (3) Quenching and cooling: After high-temperature forging, the ingot is spray-cooled to room temperature to obtain a fine lath martensitic structure ,like figure 2 shown; (4) Heating in the two-phase zon...

Embodiment 2

[0042] A high-strength martensite / ferrite dual-phase steel strengthening and toughening treatment process, the material is 18Mn2Si1Cr1Mo, and the weight is 10Kg. The difference from Example 1 is that the homogenization treatment temperature is 1120°C, the high-temperature forging ratio is 75%, the heating temperature in the two-phase zone is 760°C, and the medium-temperature forging ratio is 50%. Carry out mechanical property test to embodiment 2, tensile strength σ b =1370±20MPa, yield strength σ s =820±15MPa, elongation δ≈16%.

Embodiment 3

[0044] This case is used for comparison with Case 1 and Case 2, and the material of this comparative example is 18Mn2Si1Cr1Mo. The traditional process is used for processing, first heating to 920°C, holding for 20 minutes, then cooling to 780°C, holding for 30 minutes, and finally spraying and cooling to room temperature (without high-temperature homogenization treatment, high-temperature forging and medium-temperature forging). After this process, the microstructure of the dual-phase steel has coarse particles, and no lamellar structure is observed, such as Figure 4 shown. Tensile strength σ b =915±10MPa, yield strength σ s =560±10MPa, elongation δ≈6%. It can be seen that the strength and toughness of the "lamellar ferrite + lamellar lath martensite" dual-phase steel after the strengthening and toughening treatment by the process of the present invention can be significantly improved.

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

The invention discloses a strengthening-toughening treatment process for high-strength martensite / ferrite dual-phase steel, and the dual-phase steel. The dual-phase steel with fine crystalline grainsand a dual-phase structure of lamellar ferrite and lamellar lath martensite is finally obtained through a two-time forging process comprising high-temperature forging and medium-temperature forging, and a two-phase region quenching process, and by adopting a process of lamellar refining for replacing a traditional process of granular refining; the adverse effects on the plasticity due to the reduction of n value (strain hardening exponent) which is caused by the traditional granular refining are avoided, the lamellar refining for crystalline grains is realized, the effect of crystalline grainrefining is achieved, and strengthening-toughening treatment is completed; and the martensitic structure content in the dual-phase steel which is obtained through the treatment process is not lower than 40%, and compared with a sample treated by a common process, the tensile strength sigma b can be increased by more than 60%, and the plasticity can be increased by more than 70%, so that the strength and toughness of the martensite / ferrite dual-phase steel are remarkably improved.

Description

technical field [0001] The invention belongs to the steel material processing technology, and relates to a high-strength martensite / ferrite dual-phase steel strengthening and toughening treatment process and the dual-phase steel. Background technique [0002] Martensitic / ferritic dual-phase steel is composed of two phases: hard phase martensite and soft phase ferrite, which combines the high strength of martensite with the high toughness and ductility of ferrite. Martensitic / ferritic dual-phase steel is widely used in automobiles, oil pipelines, large-scale construction machinery and other fields, especially with the trend of lightweight automobiles, the usage rate is gradually increasing. In dual-phase steel, ferrite is the matrix phase, which can improve the plasticity and toughness of dual-phase steel, and martensite (or bainite) is the strengthening phase, distributed between the ferrite matrix phase, which can effectively improve the toughness of dual-phase steel. The ...

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): C21D8/00C22C38/38C22C38/34C22C38/02C22C38/44C22C38/58
CPCC21D8/005C21D2211/005C21D2211/008C22C38/001C22C38/02C22C38/34C22C38/38C22C38/44C22C38/58
Inventor 乔勋白旭峰孟东容刘守法党波张仪
Owner XIJING 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