Steel-magnesium dissimilar metal connection method

A technology of dissimilar metals and connection methods, used in metal processing, metal processing equipment, welding media, etc., can solve the problems of inability to achieve connection, difficult connection, and large difference in melting point, and achieve easy joint performance and welding quality control, Improve the mechanical properties and welding quality, the effect of the appropriate range of welding parameters

Inactive Publication Date: 2014-01-08
JILIN UNIV
View PDF5 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the obvious differences in the physical and chemical properties of steel and magnesium, the weldability of steel-magnesium dissimilar metals is extremely poor
So far, there is no welding process suitable for MIG welding of steel-magnesium dissimilar metals. With the aluminum (magnesium) alloy MIG welding process, the tensile strength of the steel-magnesium joint is less than 20MPa, and a reliable connection cannot be achieved
The main problems are: (1) The melting points of steel and magnesium are very different (above 800 ° C), and the boiling point of magnesium is low (1100 ° C), it is difficult to achieve connection through fusion; (2) Fe at the steel / magnesium interface There is no metallurgical reaction between Mg and liquid magnesium, and the wettability of liquid magnesium to solid steel is poor, so it is difficult to form a firm metallurgical bond; (3) The thermal expansion coefficient of magnesium and magnesium alloys is large (about twice that of steel), which is easy to cause relatively large Large welding stress, deformation, and significantly increase the tendency of cracks in the joint; (4) The solubility of hydrogen in magnesium decreases sharply with the decrease of temperature, and the weld is prone to pore defects

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
  • Steel-magnesium dissimilar metal connection method
  • Steel-magnesium dissimilar metal connection method
  • Steel-magnesium dissimilar metal connection method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] Embodiment 1. S355J2WN weathering steel and AZ61 magnesium alloy dissimilar metals were connected by MIG fusion-brazing using the method of the present invention, and the plate thicknesses of the weathering steel and the magnesium alloy were both 3.0 mm. The joint form is asymmetric V-shaped groove butt joint, the angle of weathering steel groove surface is 45°, and the angle of magnesium alloy groove surface is 30°; MIG welding uses magnesium alloy welding wire, the diameter of welding wire is 1.6mm, and the main chemical composition is Mg-5.1%Al -0.8% Zn; during the welding process, the welding wire points to the lower part of the steel groove surface about 2 / 3 of the thickness of the plate. The welding parameters are: welding current 140kA, arc voltage 21V, welding speed 0.6m / min, argon gas flow 17L / min. The MIG weld is well formed, without welding defects such as pores and cracks. The average tensile strength of the steel-magnesium welded joint is 130 MPa, and the th...

Embodiment 2

[0026] Embodiment 2. Using the method of the present invention to carry out MIG fusion-brazing connection of dissimilar metals of 16Mn steel and AZ61 magnesium alloy, the plate thicknesses of 16Mn steel and magnesium alloy are both 3.0mm. The joint form is an asymmetric V-shaped groove butt joint, the groove surface angle of 16Mn steel is 50°, and the groove surface angle of magnesium alloy is 25°; MIG welding uses magnesium alloy welding wire with a diameter of 1.6mm, and the main chemical composition is Mg-5.1%Al -0.8%Zn; during the welding process, the welding wire points to the lower part of the steel groove surface about 2 / 3 of the thickness of the plate. The welding parameters are: welding current 135kA, arc voltage 20V, welding speed 0.55m / min, argon gas flow 16L / min. The MIG weld is well formed, with welding defects such as pores and cracks. The average tensile strength of the steel-magnesium welded joint is 125 MPa, and the thickness of the intermetallic compound layer...

Embodiment 3

[0027]Example 3. Using the method of the present invention to carry out MIG fusion-brazing connection of H220YD high-strength steel and AZ31B magnesium alloy dissimilar metals, the thickness of the high-strength steel and the magnesium alloy are both 3.0mm. The joint form is an asymmetric V-shaped groove butt joint, the groove surface angle of high-strength steel is 40°, and the groove surface angle of magnesium alloy is 35°; MIG welding uses magnesium alloy welding wire with a diameter of 1.6mm, and the main chemical composition is Mg-6.6%Al -1.1%Zn; during the welding process, the welding wire points to the lower part of the steel groove surface about 2 / 3 of the thickness of the plate. The welding parameters are: welding current 150kA, arc voltage 22V, welding speed 0.7m / min, argon gas flow 18L / min. The MIG welds are well formed without welding defects such as pores and cracks. The average tensile strength of the steel-magnesium welded joints is 115 MPa, and the thickness of ...

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
diameteraaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention relates to a steel-magnesium dissimilar metal connection method in the technical fields of metallurgy, materials, machines and walking machines such as cars and railway vehicles, and belongs to the technical field of dissimilar material connection. According to the steel-magnesium dissimilar metal connection method, for the purpose of realizing steel-magnesium dissimilar metal welding, based on the reaction mechanism of Fe and Al on a fusion-soldered steel / magnesium interface, the influence rule of the interface temperature on reaction kinetics, and the properties of interface reaction products (Fe-Al intermetallic compounds), magnesium alloy welding wire components and welding parameters are optimized to promote a metallurgical reaction of the Fe and Al on the steel / magnesium interface, limit the thickness of a Fe-Al intermetallic compound layer and improve the mechanical properties and welding quality of an MIG fusion-soldered joint of steel-magnesium dissimilar metal. The process of the steel-magnesium dissimilar metal connection method comprises the steps of steel-magnesium weldment edge preparation, adoption of optimized magnesium alloy welding wires, adoption of an optimized welding technology and steel-magnesium dissimilar metal MIG fusion-soldered connection.

Description

technical field [0001] The invention relates to a steel-magnesium dissimilar metal connection method in the technical fields of metallurgy, materials, machinery, automobiles, rail passenger cars and other traveling machinery, and belongs to the technical field of dissimilar material connection. Background technique [0002] With the increasing energy shortage and environmental pollution, the mobile machinery industry such as automobiles and rail cars, which are the pillar industries of the manufacturing industry, is facing more and more severe challenges. Lightweight, energy saving, environmental protection and safety have become the inevitable trend of the development of automobiles and rail vehicles. At present, the approaches and key technologies for lightweighting automobiles and rail cars at home and abroad mainly include three aspects: the first is the application of lightweight materials; the second is structural lightweight design and optimization; the third is the u...

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): B23K9/173B23K35/28B23K9/235B23K103/18
CPCB23K9/173B23K1/00B23K33/00B23K35/24B23K2101/185B23K2103/18
Inventor 孙大千汪晓勇李洪梅谷晓燕
Owner JILIN 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