Method for repairing resistance spot welds in aluminum sheet materials

摘要

A method for repairing resistance spot welds formed between joined pieces of aluminum alloy sheet metal, such as vehicle body parts. The repair method includes resistance welding where an existing undersized spot weld is enlarged by applying electric current flow through the aluminum alloy sheets in the region around the existing defective weld. A pair of donut shaped electrodes may be used. Resistance to the current flow generates heat within the weld region. A new weld nugget is formed around the periphery of the existing weld and merges with it. The weld region is cooled and a repaired composite spot weld is formed.