About this Abstract |
Meeting |
2020 AWS Professional Program
|
Symposium
|
2020 AWS Professional Program
|
Presentation Title |
Joining Dissimilar Metals of DP590 Steel and AZ31B Magnesium Sheets by Ultrasonic Spot Welding |
Author(s) |
Jian Chen, Yong Chae Lim, Donovan Leonard, Hui Huang, Zhili Feng, Xin Sun |
On-Site Speaker (Planned) |
Jian Chen |
Abstract Scope |
With increasing demand of lightweight materials in automobiles, magnesium (Mg) alloys have received much attention due to their low density and high specific strength. However, joining Mg alloys with steel structures is challenging. This is because that the physical and chemical properties of these two materials are quite different. Mg and Fe are immiscible and no intermetallic compounds are formed in the Mg/Fe system.
DP590 steel sheets (1mm thick) with and without Zn surface coating were joined with AZ31B Mg alloy (2 mm thick) sheets by ultrasonic spot welding (USW) technique. During welding, the steel sheet was placed on the top of the Mg sheet, with the Mg sheet resting on the top of an anvil. The sonotrode tip on the top vibrates at a frequency of 20 kHz with a clamping force applied at 1.1kN. The ultrasonic welder was operated at a constant power mode (3500W) for 4s.
Lap shear tensile and fatigue tests were carried out to evaluate the mechanical properties of these joints. Post-weld cross-sectional analysis with advanced electron microscopy was also performed to study the joining mechanisms of the joints made with and without the presence of Zn coating on the steel sheets. |
Proceedings Inclusion? |
Definite: Other |