What does the resistance in Squeeze-Type Resistant Spot Welding help achieve?

In Squeeze-Type Resistant Spot Welding, resistance is a critical factor that facilitates the fusion of metal layers. The process involves applying a significant amount of pressure to the materials being welded while simultaneously passing a strong electric current through them. This electric current encounters resistance as it flows through the metals, generating heat due to the Joule heating effect. This heat is concentrated at the interface of the metal layers, raising their temperature to the point of melting, which allows the metals to fuse together.

This method creates a strong joint between the layers as the molten metal solidifies upon cooling, effectively joining the pieces without the need for additional filler materials or bonding agents. The controlled heat applied through resistance ensures that the fusion is effective and that the structural integrity of the weld is maintained. Therefore, understanding the role of resistance in this welding process is essential for achieving reliable and strong metal connections.