US Patent 10105790 Solid state joining using additive friction stir processing

Additive friction stir methods for joining materials are provided. The methods comprise providing first and second substrates to be joined; providing a forming plate comprising one or more forming cavities; placing the first and second substrates in communication with the forming plate; placing the first and second substrates in communication with each other; rotating and translating an additive friction-stir tool relative to the substrates; feeding a filler material through the additive friction-stir tool; deforming the filler material and the first and second substrates; and extruding one or more of the filler material and the first and second substrates into one or more of the forming cavities of the forming plate. Interaction of the additive friction-stir tool with the substrates generates heat and plastic deformation at the joint to weld the substrates at the joint. The methods include introduction of reinforcing material at the joint through addition of the filler material.