Joint Strength Properties of Steel and Aluminum Alloys Dissimilar Materials Resistance Spot Welded Joints with Temperature Distribution Control

Abstract

In resistance spot welding of Fe-Al dissimilar materials, it is known that intermetallic compounds are formed at the joining interface, and as these compounds thicken, joining strength in the peeling direction decreases. the formation of intermetallic compounds must be suppressed in order to improve joint strength, and one of the control methods is to control the temperature field. Therefore, In this study was to improve joining strength by controlling the temperature field. To control the temperature field, we focused on the current path, make a hole in a polyimide film, known as an insulator, and performed welding with the polyimide film between the electrode and the plate. As a result, it was found that controlling the current path between the Al and the electrode was effective in improving joining strength in the peeling direction. In addition, it was found to affect the formation state of intermetallic compounds, which is a joint property, and the properties of melting zone.