980 MPa-grade galvanized complex-phase steel and preparation method thereof

A 980mpa, multi-phase steel technology, applied in hot-dip galvanizing process, coating, improvement of process efficiency, etc., can solve the problems of insufficient yield strength and bendability of cold-rolled hot-dip galvanized steel, and achieve high bendability, high Effect of Yield Strength and Good Elongation

Active Publication Date: 2021-10-22
SHOUGANG CORPORATION
View PDF4 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In order to solve the technical problem of insufficient yield strength and bendability of cold-rolled hot-dip galvanized steel, the invention provides a 980MPa grade galvanized multiphase steel, which has high yield strength and is well matched elongation and high bendability

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
  • 980 MPa-grade galvanized complex-phase steel and preparation method thereof
  • 980 MPa-grade galvanized complex-phase steel and preparation method thereof
  • 980 MPa-grade galvanized complex-phase steel and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0064] According to another typical embodiment of the present invention, a kind of preparation method of 980MPa grade galvanized multiphase steel is provided, such as figure 2 Shown, described preparation method comprises:

[0065] S1. The molten steel is continuously cast to obtain the slab of the 980MPa grade galvanized multiphase steel;

[0066] S2. Heating the slab before rolling, hot rolling, cold rolling, continuous annealing and galvanizing to obtain the 980MPa grade galvanized multiphase steel;

[0067] Wherein, the heating temperature before rolling is 1220-1280°C.

[0068] In the present invention, by improving the chemical composition of the slab and adopting the high-temperature heating-bainite transformation rapid cooling process mode, the hard bainite phase matrix, martensite, soft ferrite and retained austenite are obtained , the prepared multi-phase steel has high yield strength, matched with good elongation and high bendability, among them, if the heating t...

Embodiment approach

[0087] As an optional implementation, the galvanizing includes:

[0088] Heating the steel strip to 450°C-460°C, and then galvanizing;

[0089] Cool to 420-430°C after galvanizing, and then cool to 250-300°C at a rate of 6°C / s-9°C / s.

[0090] In this application, cool down to 420-430°C after galvanizing. In this process, the residence time of strip steel in the equalization section, furnace nose and zinc pot should be minimized by rapid induction heating, so as to avoid partial austenite decomposition at high temperature. ; and then cooled to 250-300°C at a rate of 6°C / s-9°C / s. During this process, part of the austenite phase transforms into a martensite phase.

[0091] A 980MPa grade galvanized multi-phase steel of the present application and its preparation method will be described in detail below in combination with examples, comparative examples and experimental data.

Embodiment

[0093] A kind of 980MPa grade galvanized multiphase steel, prepared by the following method:

[0094] (1) molten steel carries out continuous casting and obtains slab, and in mass fraction, the chemical composition of described slab is:

[0095] C: 0.10% to 0.12%, Si: 0.5 to 1.0%, Mn: 2.0% to 2.5%, Alt: 0.03% to 0.1%, Ti: 0.03% to 0.04%, P≤0.01%, S≤0.01%, N ≤0.004%, the balance is Fe and trace elements.

[0096] (2) Rolling: the slab is heated to 1250°C, then hot rolled, the final rolling temperature is 890°C, and the coiling temperature is 580°C, then cold rolled, and the cold rolling reduction is 56%.

[0097] (3) Continuous annealing:

[0098] Preheat the chilled coil obtained by cold rolling to 220°C at a rate of 8°C / s to obtain strip steel;

[0099] Heating the steel strip to 650°C to realize pre-oxidation at a heating rate of 6°C / s;

[0100] further heating the pre-oxidized steel strip to 850°C to 900°C at a rate of 1°C / s to 4°C / s, and keeping it warm for 60s to 150s...

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
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention provides 980 MPa-grade galvanized complex-phase steel and belongs to the technical field of high-strength cold-rolled hot-galvanized steel. The steel comprises the following chemical components including, by mass: 0.10% to 0.12% of C, 0.5% to 1.0% of Si, 2.0% to 2.5% of Mn, 0.03% to 0.1% of Alt, 0.03% to 0.04% of Ti, less than or equal to 0.01% of P, less than or equal to 0.01% of S, less than or equal to 0.004% of N and the balance Fe and trace elements. The 980 MPa-grade galvanized complex-phase steel has high yield strength, and is matched with good ductility and high bendability. The invention further provides a preparation method of the 980 MPa grade galvanized complex-phase steel.

Description

technical field [0001] The invention belongs to the technical field of high-strength cold-rolled hot-dip galvanized steel, and in particular relates to a 980MPa grade galvanized multi-phase steel and a preparation method thereof. Background technique [0002] With the development of automobiles in the direction of energy saving, environmental protection, safety and comfort, while the body is developing in the direction of lightweight, the requirements for corrosion resistance and impact resistance are also getting higher and higher. Coupled with the competitive pressure from materials such as aluminum, magnesium, and plastics, steel sheets for automobiles are forced to develop in the direction of high-strength coatings. With the continuous expansion of the use of coated ultra-high-strength steel sheets, the requirements for formability are getting higher and higher, such as high elongation, high yield, bendability, hole expansion and so on. [0003] The structure of traditi...

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): C22C38/14C22C38/06C22C38/04C22C38/02C21D8/02C23C2/06C23C2/40
CPCC22C38/14C22C38/06C22C38/04C22C38/02C21D8/0226C21D8/0236C21D8/0273C23C2/06C23C2/40C21D2211/002C21D2211/008C21D2211/005C21D2211/001Y02P10/20
Inventor 姜英花韩赟滕华湘刘华赛邱木生阳锋王海全谢春乾李翔宇邹英
Owner SHOUGANG CORPORATION
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