The Study on the Ineffective Mechanism of Aluminum Alloy Spot Welding Electrode

Abstract

This study explored the electrode excessive burning reason caused by aluminum resistance spot welding and proposed a new electrode failure mechanism. The test shows that the oxide film of aluminum alloy workpieces causes the contact of non-uniform points between electrode and workpieces and instantaneously leads to a local explosion when setting up an electric circuit, bringing about the plastic deformation of the electrode surface in the local area, which will in turn exacerbate the contact of non-uniform points between electrode and workpieces so as to result in the serious burnout of electrodes under the interaction between local explosions and Cu-Al alloying. Cu-Al alloying and brittle material on the electrode surface caused by the contact of non-uniform points will firstly detach from the surface of electrode under the tearing force of mechanical , so that the electrode surface becomes more uneven.