Determination of process forces during remote laser beam welding for the design of fastening features

Welding of sheet metal structures in the automotive industry involves inflexible and expensive clamping devices to properly position and fasten the parts. The approach of feature-based fixturing can reduce fixtures in the joining process. It is based on part-inherent fastening features that realize the fixture functions. The proper design of these features requires knowledge of forces that result from the joining process and thus need to be compensated. For this paper, process forces were investigated during remote laser beam welding. This was achieved by using a thermomechanical simulation model. The aspects described in this paper are model build-up and validation, application of the approach to a real structure, and affiliated parameter studies. The studies show that required clamping forces depend, among other things, on the clamping condition and on the weld strategy. Finally, the simulation model allows for the design of fastening features to reduce joining fixtures in the automotive body shop.