High-strength zinc-plated steel sheet and high-strength steel sheet having superior moldability, and method for producing each

A high-strength steel plate and manufacturing method technology, applied in the direction of manufacturing tools, chemical instruments and methods, metal rolling, etc., can solve problems such as insufficient formability, brittle fracture, and processing difficulties, and achieve excellent high-speed tensile properties and formability excellent effect

Active Publication Date: 2014-04-02
NIPPON STEEL CORP
View PDF11 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] However, in recent years, with the rapid increase in strength of high-strength steel sheets, in particular, high-strength steel sheets with a maximum tensile stress of 900 MPa or more have insufficient formability, and processing with

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 zinc-plated steel sheet and high-strength steel sheet having superior moldability, and method for producing each
  • High-strength zinc-plated steel sheet and high-strength steel sheet having superior moldability, and method for producing each
  • High-strength zinc-plated steel sheet and high-strength steel sheet having superior moldability, and method for producing each

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0139] Slabs having chemical components (compositions) of A to AL shown in Tables 1 and 2 were cast, and hot rolling, cooling, coiling, and pickling were performed under the conditions shown in Tables 3 to 5 immediately after casting. In Experimental Examples 4, 9, 14, 19, 25, 29, 87, and 90, cold rolling under the conditions shown in Tables 3 to 6 was implemented after pickling the other Experimental Examples with the hot-rolled steel sheets as they were. Then, annealing was performed under the conditions shown in Tables 7 to 10 to form steel sheets of Experimental Examples 1 to 114.

[0140] In addition, Experimental Example 102 was an example exceeding the upper limit of the amount of Cu, and the result of the weldability test performed after hot rolling was bad, so the subsequent tests were discontinued.

[0141] Table 1

[0142]

[0143]

[0144] table 3

[0145]

[0146] Table 4

[0147]

[0148] table 5

[0149]

[0150] Table 6

[0151]

[0152] ...

experiment example 5

[0190] Experimental Example 5 is an example in which the hot rolling finish temperature is low, and since the microstructure is a heterogeneous structure elongated in one direction, the ductility and stretch-flangeability are inferior.

experiment example 10

[0191] In Experimental Example 10, the cooling rate after coiling was high, the precipitation of Cu particles in the hot rolling process was insufficient, and the ratio of Cu particles incoherent with bcc iron was low, so the stretch flangeability was inferior.

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

No PUM Login to view more

Abstract

This high-strength steel sheet having superior moldability while securing the high strength of a maximum tensile strength of at least 900 MPa is characterized by having a predetermined component composition, the steel sheet structure containing a ferrite phase and an austenite phase, the ratio of bcc iron and unaligned Cu grains being at least 15% of the Cu grains overall, the Cu grain density in the ferrite phase being at least 1.0x1018 grains/m3, and the average grain size of the Cu grains in the ferrite phase being at least 2.0 nm.

Description

technical field [0001] The present invention relates to high-strength steel sheets and high-strength galvanized steel sheets excellent in formability, and methods for producing them. Background technique [0002] In recent years, there has been an increasing demand for higher strength of steel sheets used in automobiles, and for the purpose of improving crash safety, etc., high-strength steel sheets with a maximum tensile stress of 900 MPa or more have been used. This high-strength steel sheet is formed in large quantities by press working similarly to the mild steel sheet at low cost, and is supplied as components. [0003] However, in recent years, with the rapid increase in strength of high-strength steel sheets, in particular, high-strength steel sheets with a maximum tensile stress of 900 MPa or more have insufficient formability, and processing with local deformation represented by stretch flange processing is relatively weak. difficult question. In addition, when a ...

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): C22C38/00B21B3/00C21D9/46C22C38/58C23C2/02C23C2/06C23C2/28C23C2/40C25D5/26C25D5/36C25D7/06
CPCC21D2211/008C23C2/28C23C2/06C22C38/04C21D9/46C22C38/001C21D2211/004C21D8/0247C22C38/44C22C38/42C21D1/19C22C38/48C22C38/06C21D2211/005B32B15/013C22C38/54C22C38/14C22C38/34C22C38/005C22C38/12C21D8/0205C21D8/0263C22C38/002C22C38/02C22C38/50C23C2/02C25D5/36C22C38/16C22C38/08C22C38/58C21D2211/002Y10T428/12799C23C2/024C23C2/0224B21B3/00C23C2/40C25D7/0614
Inventor 川田裕之丸山直纪村里映信南昭畅东昌史桑山卓也米村繁
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap