Linear friction welding (LFW) is a solid-state process capable of joining noncircular parts by oscillating one part under load to create frictional heating. From joining railroad rails to producing strong aluminum-to-steel joints, recent advancements in LFW technology are reducing equipment costs and expanding potential uses.

Typical vehicles contain more than 3000 spot welds, and failure parameters for these welds must be accurately predicted in crash simulations. A testing protocol developed at EWI for the purpose of creating spot weld failure parameters has been used since 2010 to establish these parameters for automotive manufacturers for a range of steel and aluminum stack-ups. Crash simulations in full-vehicle models show that the failure parameters created by this method are accurate for predicting the initiation of spot weld failure by comparing results with experimental data.