Method for producing hot stamped product and hot stamped product

A technology of hot stamping forming and manufacturing method, applied in the field of hot stamping products, can solve the problems of mold damage, reduction of fatigue resistance of hot stamping parts, surface damage of parts, etc., achieving sufficient strength and hardness, and no shape freezing. Problem, effect of increased forming load

Active Publication Date: 2019-03-01
JFE STEEL CORP
View PDF3 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] However, in the technique proposed in Patent Document 1, there is a problem that when the steel sheet is heated to a high temperature of around 900° C. before stamping, scale (iron oxide) is formed on the surface of the steel plate, and the scale is formed during hot stamping. Damage to the mold due to peeling during forming, or damage to the surface of parts after hot stamping
However, liquid metal embrittlement fractures caused by Zn in the plating layer may cause cracks with a depth of about 100 μm in the surface layer of hot stamped parts.
If such cracks occur, various inconveniences such as a decrease in the fatigue resistance of hot stamped parts will be brought about.

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
  • Method for producing hot stamped product and hot stamped product
  • Method for producing hot stamped product and hot stamped product
  • Method for producing hot stamped product and hot stamped product

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0136] An experiment was conducted to confirm the effect of the method for producing a hot stamped product according to the present invention, and will be described below.

[0137] Steel having the composition shown in Table 1 was melted to form a cast slab, and the cast slab was heated to 1200°C, hot rolled at a finish rolling finish temperature of 870°C, and then coiled at 600°C , making it a hot rolled steel plate.

[0138] Table 1

[0139]

[0140] Next, after pickling this hot-rolled steel sheet, it was cold-rolled at the rolling reduction ratio of 50%, and it was made into the cold-rolled steel sheet of 1.6 mm in thickness. Ac recorded in Table 1 3 The phase transition point is calculated according to the following formula (1) (William C. Leslie, translated by Naruyasu Koda, translated by Hiroshi Kumai and Tatsuhiko Noda, "Leslie Iron and Steel Materials Science", Maruzen Co., Ltd., 1985 , refer to p.273).

[0141] Ac 3(℃)=910-203√[C]+44.7×[Si]-30×[Mn]+700×[P]+40...

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
Adhesion amountaaaaaaaaaa
phase transition temperatureaaaaaaaaaa
Login to view more

Abstract

When hot stamping a surface-treated steel sheet formed by forming a Zn-Ni coating on the surface of an untreated steel sheet using a die having a die, a blank holder, and a punch to produce a hot stamped product, the die and the blank holder are used Heated to Ac 3 The edge of the surface-treated steel sheet in the temperature range of not less than the transformation point and not more than 1000°C is cooled to a temperature of not more than 550°C and not less than 400°C at a cooling rate of not less than 100°C / s, and the temperature at the edge is 550°C Press forming is started at 400° C. or lower, and after press forming, the formed body is quenched by holding the formed body at the bottom dead center of forming while sandwiching the formed body with dies.

Description

technical field [0001] The present invention relates to a hot stamped product and a method for producing the same, and more particularly to hot stamping in which a predetermined strength (tensile strength: 1180 MPa class or higher) is obtained by quenching a preheated surface-treated steel sheet while forming a shape. A method of manufacturing a molded product and a hot stamped molded product. Background technique [0002] In recent years, automobile parts have been required to be higher in strength and thinner in thickness, and the press workability has been lowered as the strength of the steel sheets used has been increased, making it difficult to process the steel sheets into desired parts shapes. [0003] As a technique to solve such a problem, there is known a method of hot stamping a raw steel plate heated to a high temperature into a desired shape using a die, and quenching the heat in the die to increase the hardness of the hot stamped part. Technology. [0004] Fo...

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 Patents(China)
IPC IPC(8): B21D22/20C25D5/26
CPCB21D22/022B21D22/208B21D24/04B21D37/16B21D22/20C23C2/06C25D3/565
Inventor 中垣内达也时田裕一簑手彻玉井良清
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