Steel sheet, surface-treated steel sheet, and manufacturing method of steel sheet and surface-treated steel sheet

A technology for surface treatment of steel plates and manufacturing methods, applied in heat treatment furnaces, manufacturing tools, heat treatment equipment, etc., can solve problems such as inability to cast continuously, and achieve excellent bending properties

Inactive Publication Date: 2011-12-14
NIPPON STEEL CORP
View PDF12 Cites 27 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the above-mentioned cooling rate can only be achieved by a thin steel billet with a thickness of 30 mm to 70 mm, s

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
  • Steel sheet, surface-treated steel sheet, and manufacturing method of steel sheet and surface-treated steel sheet
  • Steel sheet, surface-treated steel sheet, and manufacturing method of steel sheet and surface-treated steel sheet
  • Steel sheet, surface-treated steel sheet, and manufacturing method of steel sheet and surface-treated steel sheet

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0108] Steels having the chemical compositions shown in Table 1 were melted using a converter. Next, continuous casting was performed under conditions such that the solidification rate at a position at a depth of 10 mm from the surface of the slab was as shown in Table 2, to produce a slab with a thickness of 245 mm.

[0109] The steel slabs were hot-rolled under the conditions shown in Table 2, pickled thereafter, and then cold-rolled under the conditions shown in Table 2 to obtain cold-rolled steel sheets with a thickness of 1.2 mm.

[0110] Table 1

[0111]

[0112] Table 2

[0113]

[0114] Test pieces for heat treatment were collected from the obtained cold-rolled steel sheets, and heat treatment corresponding to the heating curve of a continuous annealing facility or a continuous hot-dip galvanizing facility was performed as shown in Table 3.

[0115] table 3

[0116]

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
Tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention relates to a steel sheet, a surface-treated steel sheet, and a method for producing the same. The high-strength steel sheet having excellent bending strength in the form of a tensile strength of 590 MPa or higher has a chemical composition of C: 0.03 to 0.20%, Si: 0.005 to 2.0%, Mn: 1.2 to 3.5%, P=0.1% or less, S=0.11% or less, sol. Al: 0.001 to 1.0%, N=0.01%, and Bi: 0.0001 to 0.05%; arbitrarily contains Ti<=0.3%, Nb<=0.3%, V<=0.3%, Cr<=1%, Mo<=1%, Cu<=1%, Ni<=1%, Ca<=0.01%, Mg<=0.01%, REM<=0.01%, Zr<=0.01%, and B<=0.01%; and has an Mn segregation ratio (Mnmax/Mnav) of less than 1.30 as calculated from the average Mn concentration (Mnav) and the maximum Mn concentration (Mnmax) at a position of (1/20) the depth of sheet thickness from the steel sheet surface.

Description

technical field [0001] The present invention relates to steel sheets and surface-treated steel sheets and methods for their treatment. More specifically, the present invention relates to high-strength steel sheets and surface-treated steel sheets suitable as raw materials for automobile reinforcement members, automobile seat members, and the like, and methods for their production. Background technique [0002] In the automobile industry, high-strength steel sheets with excellent workability are very effective for weight reduction related to improvement of automobile safety and fuel economy, and thus attract more and more attention. In recent years, the number of members made of high-strength steel plates per vehicle has increased. Therefore, an extremely high level of bendability is also required for a high-strength steel sheet having a tensile strength of 590 MPa or more. In particular, unprecedented severe bendability and higher strength are required for members having p...

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): C22C38/00B21B3/00B22D11/00C21D9/46C22C38/06C22C38/58
CPCC21D8/0273C21D8/0236C21D8/0215C21D8/0226C22C38/06C22C38/04C22C38/002C22C38/02
Inventor 林宏太郎水上英夫
Owner NIPPON STEEL CORP
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