Effect of electrode tip geometry on electrode degradation during resistance spot welding zinc coated sheet steel

The effect of electrode tip geometry on electrode degradation during resistance spot welding zinc coated steel sheet was investigated by scanning electron microscope and energy dispersive X-ray spectrometer. The results show that domed electrode degradation mechanism is basically caused by wear due to fracture of local welding between the electrode tip surface and zinc coated sheet steel happen at electrode surf ace, and alloying between electrode and zinc on coated sheet steel during resistance spot welding zinc coated sheet steel. The truncated electrode degradation mechanism is basically caused by wear and a little alloying, and by a mass of deformation on electrode tip.