Investigation into the Effect of Spot Weld Electrode Life and Quality on the Corrosion Behavior of Galvanized Automotive Steel Using the Three-dimensional Scanning Vibrating Technique

The Three dimensional Scanning Vibrating Electrode Technique (3D SVET) - which allows the measurement of non-planar samples - has been used to investigate the effects that spot weld tip lifetime (i.e. number of welds produced by a tip between dressings) has on corrosion of spot welded steel. Cathodic activity is concentrated within the spot weld when weld tips are fresh (used for 1000 welds) whilst anodic activity is found on the spot weld perimeter. This is due to copper deposition within the weld and zinc enrichment around the spot weld as a result of the welding process.