High-strength galvanized steel sheet, high-strength member, and manufacturing methods therefor

A technology of galvanized steel sheet and manufacturing method, applied in manufacturing tools, hot-dip plating process, furnace, etc., can solve the problems of easy formation of micro-holes, deterioration of bendability, etc., and achieve improved collision safety, platability and bendability excellent effect

Active Publication Date: 2020-11-13
JFE STEEL CORP
View PDF5 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In particular, in the case of a steel plate composed of two or more types of steel structure with different hardness, deformation concentrates at the interface of the steel structure, and micropore defects are likely to be formed, resulting in poor 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
  • High-strength galvanized steel sheet, high-strength member, and manufacturing methods therefor
  • High-strength galvanized steel sheet, high-strength member, and manufacturing methods therefor
  • High-strength galvanized steel sheet, high-strength member, and manufacturing methods therefor

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0146] In order to confirm the influence of the amount of hydrogen in steel, the study shown in Example 1 was carried out.

[0147] Molten steel with the composition shown in Table 1 was smelted in a converter to produce slabs with an average flow rate of molten steel at the solidification interface near the meniscus of the mold at 18 cm / sec and an average casting speed of 1.8 m / min. This slab was heated to 1200°C, and a hot-rolled coil was produced at a finishing temperature of 840°C and a coiling temperature of 550°C. The hot-rolled steel sheets obtained from the hot-rolled coils were pickled, and then cold-rolled steel sheets with a thickness of 1.4 mm were produced at a cold reduction rate of 50%. The cold-rolled steel sheet was annealed in an annealing furnace atmosphere with various hydrogen concentrations and a dew point of -30°C, and heated to an annealing temperature of 790°C (within the range of Ac3 point + 20°C or lower), so as to increase the temperature from the a...

Embodiment 2

[0156] In Example 2, the following galvanized steel sheets were manufactured and evaluated.

[0157] Melt molten steel with the composition shown in Table 2 using a converter, reheat the slab cast under the conditions shown in Table 3 to 1200°C, and perform hot rolling at a finish rolling temperature of 800 to 830°C to make the coil The temperature at the time of coiling was 560 degreeC, and the hot rolled coil was manufactured. The hot-rolled steel sheet obtained from the hot-rolled coil was pickled, and the steel sheet was subjected to the processes of cold rolling, annealing, coating treatment, width trimming, and post-treatment under the conditions shown in Table 3 to produce a 1.4 mm thick galvanized steel sheet. steel plate. It should be noted that immediately after the plating treatment (galvanizing treatment), the alloying treatment of galvanizing was performed under the conditions of 500° C. for 20 seconds. In addition, the steps of width trimming and post-processin...

Embodiment 3

[0185] The galvanized steel sheet of the production condition No. 1 (example of the present invention) in Table 3 of Example 2 was press-formed to manufacture the parts of the example of the present invention. In addition, the galvanized steel sheet of the manufacturing condition No.1 (example of the present invention) in Table 3 of Example 2 and the galvanized steel sheet of the manufacturing condition No. 2 (example of the present invention) of Table 3 of Example 2 were carried out by spot welding Joining, the parts of the example of this invention were manufactured. It was confirmed that the components of these examples of the present invention are excellent in bendability and plating property, and thus can be applied to automobile parts and the like.

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
particle sizeaaaaaaaaaa
tensile stressaaaaaaaaaa
Login to view more

Abstract

The present invention addresses the problem of providing a high-strength galvanized steel sheet having excellent plating properties and bendability, and providing a high-strength member, and manufacturing methods therefor. This high-strength galvanized steel sheet comprises: a steel sheet having a component composition which contains prescribed component elements, and for which the mass ratio (Si / Mn) of Si content with respect to Mn content in the steel is at least 0.1 but less than 0.2, the remainder comprising Fe and unavoidable impurities, and a metal structure for which the average particle size of inclusions present in a range from the surface to a position at 1 / 3 the sheet thickness and containing at least one element among Al, Si, Mg, and Ca is 50 mum or less, and the average nearest distance of the inclusions is 20 mum or greater; and, on the surface of the steel sheet, a zinc plating layer for which the plating adhesion amount per surface is 20-120 g / m<2>. The amount of diffusible hydrogen in the steel is less than 0.25 mass ppm, and the tensile strength is 1100 MPa or higher.

Description

technical field [0001] The present invention relates to a high-strength galvanized steel sheet excellent in platability and bendability, suitable for building materials and crash-resistant parts of automobiles, high-strength parts, and methods for producing them. Background technique [0002] Recently, there is an increasing demand for improved crash safety and fuel efficiency of automobiles, and steel sheets used as parts materials have been increasing in strength. In addition, automobiles are widely used around the world and are used for various purposes in various regions and climates. For this reason, high rust resistance is required for steel sheets used as component materials. [0003] In general, if the strength of a steel sheet increases, its workability decreases. In particular, the plated steel sheet tends to be inferior in workability compared to the unplated steel sheet. [0004] Furthermore, it is known that it is difficult to form a high-quality plated film o...

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): C22C38/00C21D9/46C22C38/06C22C38/60C23C2/06C23C2/40C22C18/00C22C18/04
CPCC22C38/00C22C18/04C23C2/06C22C18/00C21D9/46C22C38/06C23C2/40C22C38/60C21D8/0226C21D8/0236C21D8/0263C21D8/0426C21D8/0436C21D8/0463C22C38/02C22C38/04C22C38/08C22C38/12C22C38/14C22C38/18C22C38/22C22C38/24C22C38/26C22C38/28C22C38/32C22C38/40C21D2211/005C21D2211/008C21D8/02C21D1/26C21D1/76C23C2/26C22C38/001C21D8/0247C21D8/0205C21D2211/001C21D2211/002C22C38/002C22C38/42C22C38/44C22C38/46C22C38/50C22C38/54
Inventor 吉富裕美木庭正贵中垣内达也铃木善继
Owner JFE 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