450MPa-grade hot-dip galvanized dual-phase steel with high work hardening rate and surface quality and production method of 450MPa-grade hot-dip galvanized dual-phase steel

A production method and 450mpa technology, applied in hot dip plating process, metal material coating process, coating and other directions, can solve the problem of low work hardening rate of 450Mpa hot-dip galvanized dual-phase steel, and improve the initial work hardening rate , the effect of reducing yield strength and increasing yield

Pending Publication Date: 2022-03-01
MAANSHAN IRON & STEEL CO LTD
View PDF9 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] Aiming at the problem of low work hardening rate of the existing 450Mpa grade hot-dip galvanized dual-phase steel, the present invention provides a 450MPa grade hot-dip galvanized dual-phase steel, which has a relatively high work hardening rate and meets the requirements of use

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
  • 450MPa-grade hot-dip galvanized dual-phase steel with high work hardening rate and surface quality and production method of 450MPa-grade hot-dip galvanized dual-phase steel
  • 450MPa-grade hot-dip galvanized dual-phase steel with high work hardening rate and surface quality and production method of 450MPa-grade hot-dip galvanized dual-phase steel
  • 450MPa-grade hot-dip galvanized dual-phase steel with high work hardening rate and surface quality and production method of 450MPa-grade hot-dip galvanized dual-phase steel

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0050] Technical scheme implementation steps of the present invention are as follows:

[0051] (1) Smelting and pouring into slabs according to the process route of molten iron pretreatment→converter smelting→alloy fine-tuning→LF furnace refining→continuous casting;

[0052] (2) The slab is heated to 1210-1250°C, after dephosphorization and 6 passes of rough rolling, and 7 passes of finish rolling, the start temperature of finish rolling is 1000-1080°C, and the outlet temperature is 860-900°C, Laminar cooling to 520-560°C to obtain a hot-rolled sheet, which is then coiled and naturally cooled in the air;

[0053] (3) Cold rolling after normal pickling, the cold rolling reduction rate is 55% to 80%;

[0054] (4) Carry out continuous annealing + hot-dip galvanizing, heat the steel coil to 770-790°C, dew point in the furnace ≤ -40°C, oxygen content ≤ 5ppm, slow cooling after heat preservation, and cool at a cooling rate of 3-6°C / s to 640-660°C, and then cooled to 470-490°C at a...

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
yield strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses 450MPa-grade hot-dip galvanized dual-phase steel and a production method thereof, and belongs to the field of galvanized automobile steel manufacturing, the 450MPa-grade hot-dip galvanized dual-phase steel adopts a low-carbon-low-manganese component design of trace Si, low Mo and high Cr, processes of coiling at a low temperature of 520-560 DEG C, slow cooling at a temperature of 640-660 DEG C and rapid cooling at a temperature of more than or equal to 10 DEG C are carried out, and the 450MPa-grade hot-dip galvanized dual-phase steel is prepared by matching a dew point in a furnace at a temperature of less than or equal to-40 DEG C and an oxygen content of less than or equal to 5ppm. And obtaining the 450MPa-grade hot-dip galvanized dual-phase steel under the atmosphere that the dew point of a furnace nose is not more than-20 DEG C. According to the produced hot-dip galvanized dual-phase steel with the tensile strength of 450 MPa, the uniform elongation is 18%-23%, the work hardening rate n value is not lower than 0.19, the after-fracture elongation A80 reaches up to 28%-33%, and the hot-dip galvanized dual-phase steel is suitable for being used as a high-drawing and high-flanging complex forming automobile part.

Description

technical field [0001] The invention belongs to the field of galvanized automobile steel manufacturing, and more specifically relates to a 450MPa grade hot-dip galvanized dual-phase steel and a production method thereof. The production method involved in the invention is suitable for continuous hot-dip plating of pure galvanized steel sheets for automobiles. Background technique [0002] Compared with cold-rolled dual-phase steel, hot-dip galvanized dual-phase steel is not only beneficial to forming but also ensures sag resistance and improves the absorption capacity of collision energy, which solves the contradiction between high strength and formability well, and because the zinc layer on the surface It has good corrosion resistance and is considered to be an ideal material for the continuous lightweight design of future cars. However, due to the large differences between the galvanizing production line and the continuous annealing production line, such as a small cooling...

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): C22C38/02C22C38/04C22C38/06C22C38/22C23C2/06C23C2/20C23C2/40C21D1/26C21D6/00C21D8/02
CPCC22C38/02C22C38/04C22C38/06C22C38/22C21D1/26C21D6/002C21D6/005C21D6/008C21D8/0205C21D8/0221C21D8/0247C23C2/06C23C2/40C23C2/20C21D2211/005C21D2211/008C21D2211/002C21D2211/009
Inventor 葛浩何丹丹李贤强崔磊马二清
Owner MAANSHAN IRON & STEEL CO LTD
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