A kind of low-density fe-mn-al-c hot-rolled q&p steel and its manufacturing method

A fe-mn-al-c, manufacturing method technology, applied in low-density Fe-Mn-Al-C hot-rolled Q&P steel and its manufacturing field, can solve the problem of difficulty in obtaining uniformity and post-break elongation, difficulty in low-temperature quenching control, Problems such as uneven structure and performance, to achieve the effect of solving uneven cooling, improving surface quality, and accurate final cooling temperature

Active Publication Date: 2020-11-27
NORTHEASTERN UNIV LIAONING
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the existing hot-rolled Q&P research relies heavily on online rapid cooling, and the control of low-temperature quenching is difficult, resulting in problems such as poor plate shape and uneven structure and properties, which restrict its further industrial application.
In addition, the retained austenite content in the Q&P structure obtained by most current studies is low, generally less than 15%, making it difficult to obtain good uniformity and elongation after fracture for high-strength (greater than 1100MPa) Q&P structures

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
  • A kind of low-density fe-mn-al-c hot-rolled q&p steel and its manufacturing method
  • A kind of low-density fe-mn-al-c hot-rolled q&p steel and its manufacturing method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] In this embodiment, the composition of the low-density Fe-Mn-Al-C hot-rolled Q&P steel is: C: 0.23%, Mn: 3.0%, Al: 1.8%, and the rest is Fe.

[0036] After smelting and forging, the billet is heated to 1200°C and kept for 1.5 hours. The first-stage rolling is carried out at 1190°C, and then the second-stage rolling is carried out by air cooling to 920°C. The final rolling temperature is 880°C, air-cooled to 340°C, and then slowly cooled to room temperature with the furnace.

[0037] Its performance indicators are as follows after mechanical performance testing: the yield strength is 660MPa, the tensile strength is 1135MPa, the elongation after fracture is 19.20%, and the strong-plastic product is 21.790GPa.%. Such as figure 1 As shown, the metallographic structure is composed of ferrite, martensite and retained austenite, the volume fraction of ferrite is 14%, the volume fraction of retained austenite is 23.25%, and the rest is martensite. Such as figure 2 As shown,...

Embodiment 2

[0039] In this embodiment, the composition of the low-density Fe-Mn-Al-C hot-rolled Q&P steel is: C: 0.25%, Mn: 2.8%, Al: 2.0%, and the rest is Fe.

[0040] After smelting and forging, the billet is heated to 1200°C and kept for 1.5 hours. The first-stage rolling is carried out at 1180°C, and then the second-stage rolling is carried out by air cooling to 925°C. The final rolling temperature is 870°C, air-cooled to 320°C, and then slowly cooled to room temperature with the furnace.

[0041]Its performance indicators are as follows after mechanical performance testing: the yield strength is 630MPa, the tensile strength is 1151MPa, the elongation after fracture is 20.5%, and the strong-plastic product is 23.595GPa.%. The metallographic structure is composed of ferrite, martensite and retained austenite. The volume fraction of ferrite is 14%, the volume fraction of retained austenite is 21.92%, and the rest is martensite. Such as figure 2 As shown, it can be seen from the XRD d...

Embodiment 3

[0043] In this embodiment, the composition of the low-density Fe-Mn-Al-C hot-rolled Q&P steel is: C: 0.24%, Mn: 2.9%, Al: 2.2%, and the rest is Fe.

[0044] After smelting and forging, the billet is heated to 1210°C and kept for 1.5 hours. Carry out the first stage rolling at 1170°C, then air cool to 930°C for the second stage rolling, the final rolling temperature is 890°C, air cool to 300°C, and then slowly cool to room temperature with the furnace.

[0045] Its performance indicators are as follows after mechanical performance testing: the yield strength is 653MPa, the tensile strength is 1161MPa, the elongation after fracture is 19.20%, and the strong-plastic product is 22.290GPa.%. The metallographic structure is composed of ferrite, martensite and retained austenite. The volume fraction of ferrite is 13%, the volume fraction of retained austenite is 24.16%, and the rest is martensite. Such as figure 2 As shown, it can be seen from the XRD detection that there are seve...

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
tensile strengthaaaaaaaaaa
yield strengthaaaaaaaaaa
yield strengthaaaaaaaaaa
Login to view more

Abstract

The invention belongs to the technical field of steel alloy materials and particularly relates to low-density Fe-Mn-Al-C hot-rolled Q&P steel and a manufacturing method of the low-density Fe-Mn-Al-C hot-rolled Q&P steel. The low-density hot-rolled Q&P steel comprises, by weight percentage, 0.22-0.25% of C, 2.8-3.2% of Mn, 1.8-2.2% of Al and the balance Fe. After controlled rolling, the experimental steel is air-cooled to 280-340 DEG C on line and then furnace-cooled to the room temperature, finally a small amount of ferrite, martensite and retained austenite complex phase Q&P structure is obtained, the tensile strength is larger than or equal to 1,135 MPa, and the elongation is larger than 19%. Compared with existing Q&P steel, by the adoption of the low-density Fe-Mn-Al-C hot-rolled Q&P steel and the manufacturing method, through reasonable composition design, the density of the experimental steel is reduced, the dependence of martensitic transformation on the cooling speed is reduced, the quenching process is replaced with air cooling, and the problems of uneven microstructure and property, poor plate shape and the like caused by on-line low-temperature quenching (below Ms) are solved.

Description

technical field [0001] The invention belongs to the technical field of iron and steel alloy materials, and in particular relates to a low-density Fe-Mn-Al-C hot-rolled Q&P steel and a manufacturing method thereof. Background technique [0002] With the increasingly prominent contradiction between energy, environment and sustainable development, the automotive industry is developing towards energy saving, consumption reduction, low carbon, environmental protection and green, which poses new challenges to automotive materials. Lightweight and safety are important indicators to measure automotive materials, so it is particularly important to design and develop low-density high-strength plastic materials. In addition, iron and steel enterprises are facing severe situations such as overcapacity, unbalanced product structure, and high energy consumption, and there is an urgent need to develop high-quality green steel materials with reduction processes. [0003] Quenching-partitio...

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 Patents(China)
IPC IPC(8): C22C38/04C22C38/06C21D8/02C22C33/04
CPCC21D8/0226C21D8/0263C22C33/04C22C38/04C22C38/06
Inventor 袁国李云杰康健毛起佳王晓晖李振垒王国栋
Owner NORTHEASTERN UNIV LIAONING
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