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

High-strength steel sheet and production method for same, and production method for high-strength galvanized steel sheet

A technology of high-strength steel sheet and manufacturing method, applied in manufacturing tools, hot-dip plating process, coating and other directions, can solve problems such as poor shape, reduced mass production efficiency, increased deviation, etc., and achieves high utilization value and improved fuel efficiency. , the effect of excellent ductility

Active Publication Date: 2017-04-19
JFE STEEL CORP
View PDF10 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] However, the amount of shape change is estimated based on TS. Therefore, when the TS of the steel sheet fluctuates, the deviation between the predicted value of shape change and the actual amount of shape change increases, causing shape defects.
In addition, steel sheets with such poor shapes need to be corrected one by one by sheet metal processing after stamping, which significantly reduces mass production efficiency.

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
  • High-strength steel sheet and production method for same, and production method for high-strength galvanized steel sheet
  • High-strength steel sheet and production method for same, and production method for high-strength galvanized steel sheet
  • High-strength steel sheet and production method for same, and production method for high-strength galvanized steel sheet

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0171] The steel having the composition shown in Table 1 and the balance consisting of Fe and unavoidable impurities was smelted in a converter, and a billet was produced by a continuous casting method. The obtained steel slab was heated under the conditions shown in Table 2, and hot rolled to obtain a steel sheet. Then, the steel sheet is subjected to pickling treatment. Then, for Nos. 1-22, 24, 25, 28, 30, 31, 33, 35-40, 42, 44-56 shown in Table 2, the steel sheets were hot-rolled under the conditions shown in Table 2. Heat treatment. For Nos. 31, 33, 35-40, 42, 44, the hot-rolled sheet was subjected to pickling treatment after heat treatment.

[0172] Next, after cold rolling the steel sheet under the conditions shown in Table 2, the steel sheet was subjected to two or three annealing treatments under the conditions shown in Table 2 to obtain a high-strength cold rolled steel sheet (CR).

[0173] Furthermore, a part of the high-strength cold-rolled steel sheet (CR) is galvani...

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
tensile strengthaaaaaaaaaa
elongationaaaaaaaaaa
Login to View More

Abstract

The present invention provides a high-strength steel sheet having a tensile strength (TS) of at least 780 MPa, excellent ductility and stretch flangeability, and excellent material-quality stability, achieved by: having a specific component composition; the steel structure having, in terms of area ratio, a total of ferrite and bainitic ferrite of 25-80%, and 3-20% martensite, and having, in terms of volume fraction, at least 10% retained austenite; the average crystalline particle diameter of the retained austenite being not more than 2[mu]m; the average Mn volume (mass%) in the retained austenite being at least 1.2 times the Mn volume (mass%) in the steel; and the area ratio of retained austenite that has an average C volume (mass%) of at least 2.1 times the C volume (mass%) of the steel being at least 60% of the area ratio of the total retained austenite.

Description

Technical field [0001] The present invention relates to a high-strength steel sheet with excellent formability, mainly suitable for structural members of automobiles, and a method for manufacturing the same. In particular, it is necessary to obtain a tensile strength (TS) of 780 MPa or more, excellent ductility, and excellent stretch flangeability. , And high-strength steel plate with excellent material stability. Background technique [0002] In recent years, in order to ensure the safety of the crew in the event of a collision and improve the fuel efficiency brought about by the weight reduction of the car body, the application of high-strength steel plates with a tensile strength (TS) of 780MPa or more and a thinner plate is being actively promoted. For the dynamics of automotive structural components. [0003] Furthermore, recently, the application of extremely high-strength steel sheets with 980 MPa class and 1180 MPa class TS has been studied. [0004] However, in general, in...

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): C22C38/00C21D9/46C22C38/04C22C38/60C22C18/04
CPCC22C18/04C22C38/00C22C38/04C22C38/60C21D8/0205C21D8/0226C21D8/0236C21D8/0263C21D8/0273C22C38/001C22C38/02C22C38/06C21D2211/001C21D2211/002C21D2211/005C21D2211/008C23C2/02C21D9/46C21D6/005C21D6/008C21D8/0278C22C38/002C22C38/005C22C38/008C22C38/12C22C38/14C22C38/16C22C38/38C23C2/06C23C2/024C23C2/0224C23F17/00
Inventor 川崎由康松田广志小幡美绘金子真次郎横田毅濑户一洋
Owner JFE STEEL CORP
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