Solid state weld is one type of bond that forms between metals; others are fusion, solder, and braze. Solid state bond produces a direct bond between two components without the need for any reaction, filler, or fusion at the interface. Solid state welding is quite misunderstood and this video attempts to explain how such a bond forms at the interface. Solid state bonds are common in many welding processes including resistance welding, friction welding, friction stir welding, ultrasonic welding, explosion welding, magnetic impulse welding, and cold welding. Solid state bond can be as strong as a fusion bond for a given chemistry.
