Comparison between Fusion Welding and Friction Stir Welding
In tradional welding, the two materials are heated to their melting point, and then the welder operator stirs the two materials together until they form a very strong bond. The problem arises when the areas adjacent to the welds are inspected, and it is seen that while the weld may be extremely strong, the adjacent areas are the weakest links.
In Friction Stir Welding, the two pieces of material are not melted, and therefore the process is much safer for the operator. Also, because the pieces are plastically deformed into one another, there is no weakened area near the welded joint. In aerospace applications, this is a very important quality of the joint, because failure while flying or while in orbit is catastrophic for both the vehicle as well as the passengers.
