High-strength aluminum alloy sheet resistance spot welding molten core inner crack healing method

A technology of resistance spot welding and aluminum alloy, which is applied in the direction of non-electric welding equipment, welding equipment, metal processing, etc., can solve the problems of low efficiency, achieve the effects of promoting healing, improving healing efficiency, and shortening the friction residence time

Active Publication Date: 2015-05-06
NORTHWESTERN POLYTECHNICAL UNIV
View PDF5 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] In order to overcome the inefficiency of the existing method for healing cracks in the nugget of resistance spot welding, the present invention provides a method for healing cracks in the nugget of high-strength aluminum alloy sheet resistance spot welding

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 aluminum alloy sheet resistance spot welding molten core inner crack healing method
  • High-strength aluminum alloy sheet resistance spot welding molten core inner crack healing method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0021] refer to Figure 1-2 . The specific steps of the healing method of cracks in the high-strength aluminum alloy sheet resistance spot welding nugget of the present invention are as follows:

[0022] 1. Make healing tools.

[0023] Both the upper healing tool 1 and the lower healing tool 7 are made of 4Cr5MoSiV1 hot work die steel, and the diameter of the shoulder 3 is 1.5-2.0 times of the indentation diameter of the spot welding joint 4 . In order to promote the metal flow in the area of ​​the spot welding nugget 5 and realize the flow transfer and dynamic recrystallization of the thermoplastic metal around the inner crack 6, three involute grooves with a depth of 0.3mm are processed on the friction surface 10 of the shoulder 3.

[0024] 2. Determine the healing parameters.

[0025] The pressing amount 8 of the upper and lower healing tools 1 and 7 is the same, and its value is slightly greater than the indentation depth of the spot welding joint 4 . Parameters such a...

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
diameteraaaaaaaaaa
heightaaaaaaaaaa
Login to view more

Abstract

The invention discloses a high-strength aluminum alloy sheet resistance spot welding molten core inner crack healing method. The method is used for solving the technical problem that an existing resistance spot welding molten core inner crack healing method is poor in efficiency. According to the technical scheme, the mode that an upper shaft shoulder and a lower shaft shoulder rotate and rub synchronously to generate heat is adopted, double-faced synchronous healing processing is conducted on the same molten core inner crack on an upper face and a lower face of a spot welding joint, compared with healing processing sequentially conducted on faces separately, the friction residence time can be shortened, and healing efficiency is improved; according to the characteristic that a high-strength sheet aluminum alloy spot welding structure piece is poor in deformation resistance, through self-supporting functions of the upper shaft shoulder and the lower shaft shoulder, no base plate is needed, and healing of mass molten core inner cracks of large sheet multi-point spot welding structure pieces can be achieved; the friction face of a healing tool is provided with a groove with an involute, flowing of thermoplastic metal is facilitated, and healing of the inner cracks can be promoted.

Description

technical field [0001] The invention relates to a method for healing cracks in a resistance spot welding nugget, in particular to a method for healing cracks in a high-strength aluminum alloy sheet resistance spot welding nugget. Background technique [0002] High-strength aluminum alloy has narrow plastic zone, good thermal conductivity, poor high-temperature plasticity and large linear expansion coefficient. During resistance spot welding, the solidification process of the nugget will generate great shrinkage stress, and cracks are prone to appear in the nugget. The cracks in the nugget will continue to expand under the action of load, and eventually lead to structural fracture, resulting in permanent failure of the structure. Therefore, it is of great significance to heal the cracks in the nugget of resistance spot welding of high-strength aluminum alloy. [0003] Known healing methods for internal cracks include high-temperature thermal energy method, thermal-mechanical...

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): B23K20/12B23K20/24
CPCB23K20/123B23K20/2336B23K20/24B23K2101/185B23K2103/10
Inventor 张勇胡喆马铁军李文亚杨夏炜田锦
Owner NORTHWESTERN POLYTECHNICAL UNIV
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