Stir friction both-side welding method for medium-thickness plate

A friction stir and double-sided welding technology, applied in welding equipment, non-electric welding equipment, welding/welding/cutting items, etc., can solve the problem of low connection strength, improve mechanical properties, reduce thermal gradient, and improve plastic flow Effect

Inactive Publication Date: 2014-07-16
BEIJING INSTITUTE OF TECHNOLOGYGY
View PDF5 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Aiming at the problem of low connection strength of existing medium and thick plate joints, the purpose of the present invention is to provide a friction stir double-sided welding method

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
  • Stir friction both-side welding method for medium-thickness plate
  • Stir friction both-side welding method for medium-thickness plate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0018] The 10mm thick rare earth magnesium alloy plate is docked and fixed on the backing plate; the shaft shoulder of the stirring head is in the shape of a double concave ring, with a diameter of 20mm; mm. Center the rotating stirring head with the welding face. When starting welding, the stirring head is inserted into the starting position of welding at an insertion speed of 20mm / min, and the pressing amount of the shoulder is 0.2mm, and stays for 2s; when starting to move, keep the rotating speed of the stirring head at 600r / min, and the welding speed is 80mm / min ; After the stirring head stops moving, stay for 2 seconds and pull out the stirring head, and the welding is completed, and a weld seam is obtained. Turn the workpiece over, and use the back of the starting position of the primary welding seam as the starting position of the secondary welding, and perform the same direction welding of the secondary welding seam, and the welding parameters are the same as steps 2...

Embodiment 2

[0021] The 10mm thick rare earth magnesium alloy plates are docked and fixed on the backing plate; the preparation method of the primary weld is the same as in Example 1 to obtain the primary weld; the workpiece is turned over, and the back of the primary weld end position is used as the starting point of the secondary weld. At the initial position, the anisotropic welding of the secondary weld seam is carried out, and the welding parameters are the same as in Embodiment 1. The complete weld seam of friction stir double-sided welding is obtained at the end of welding.

[0022] The upper and lower surfaces of the welded joint are well-formed, without major deformation, and without obvious defects; the quasi-static tensile mechanical performance test shows that the tensile strength of the joint is 267.8MPa, reaching 89.3% of the strength of the base metal, and the fracture is located at the thermal area of ​​influence.

Embodiment 3

[0024] The 20mm thick AZ80 magnesium alloy is butted in the same direction by friction stir double-sided welding, and the tensile strength of the base metal is 299MPa. The plates are butted and fixed on the backing plate. The shaft shoulder of the stirring head used is in the shape of a double concave ring with a diameter of 22mm; the stirring needle is a conical right-handed thread with a diameter of 6-10mm and a length of 9.7mm. The process parameters of the two welding are the same, respectively: the welding rotation speed is 250r / min, the welding speed is 80mm / min, and the pressing amount is 0.2mm. Finally, a complete weld seam of friction stir double-sided welding in the same direction is obtained.

[0025] The upper and lower surfaces of the welded joint are well formed without obvious defects; the quasi-static tensile mechanical property test shows that the tensile strength of the joint is 262.2MPa, reaching 87.7% of the base metal strength, and the fracture position is...

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
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention relates to a stir friction both-side welding method for a medium-thickness plate and belongs to a novel metal material connection method. The welding method includes the following steps that firstly, magnesium alloy plates to be welded are in butt joint and are fixed to a worktable; secondly; secondly an FSW device is used for performing both-side welding graded welding on the magnesium alloy plates, and primary welding joint welding is performed on a stirring head at the rotating speed omega, the welding speed Vh and the pressing amount h; thirdly, a workpiece is overturned, secondary welding joint welding is performed on the back of a primary welding joint, and welding parameters are identical to those in the second step. According to the stir friction both-side welding method, due to the fact that the initial position of a secondary welding joint is adjusted, the plastic flow of metal can be improved, asymmetry of heating power influence areas on the two sides of cross sections of welding joints is easily avoided, and the mechanical property on connectors is improved. The defect that the root of the medium-thickness plate is not welded thoroughly is overcome, and the possibility that the metal of the surface-layer welding joints is locally overheated is also reduced through twice welding.

Description

technical field [0001] The invention belongs to the technical field of welding technology in material processing engineering, and in particular relates to a friction stir double-sided welding method for medium-thick plates. Background technique [0002] Magnesium alloy has high specific strength and specific stiffness, high dimensional stability, good vibration damping performance, thermal conductivity, casting performance and machinability. It is currently the lightest metal structural material and special-purpose functional material in industry. Therefore, magnesium alloys have been widely used in industrial fields such as automobiles, aerospace, and rail transit. Traditionally, the connection of magnesium alloys is mainly through fusion welding, which is prone to defects such as evaporation, coarse grains and high residual stress. The new type of friction stir welding is a solid phase connection method, which has no defects of fusion welding, small residual stress and de...

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
CPCB23K20/12B23K20/24B23K2101/185B23K2103/08
Inventor 杨素媛刘冬冬
Owner BEIJING INSTITUTE OF TECHNOLOGYGY
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