Friction Stir Welding
The friction stir welding process is carried out using friction stir welding machinery. A cylindrical, shouldered, wear-resistant pin "P" having a tip "R" is rotated and forced against the joint path. The friction between the pin P and the members to be joined causes the material to soften and flow without melting. Thus, friction stir welding is a type of solid state bonding process. The following exemplary parameters have been found to produce an acceptable friction stir welded bond: pin speed about 700 to about 900 RPM; traversing speed about 10 cm/min. (4 in/min.) to about 15.2 cm/min. (6 in/min.); and force on the pin P about 499 kg (1100 lbs.) to about 635 kg (1400 lbs.). The pin P moves along the joint path, leaving the members bonded together behind it. (RDC 8/19/2011) [Manicke and Helder, US Patent 7,879,421 (2/1/2011)
Recent US Patents
2/1/2011
7,879,421
Friction stir welding of fiber reinforced thermoplastics
Manicke and Helder of General Electric Company, New York, developed fiber reinforced components with specific fiber orientation so that the components can be joined by friction stir welding. (RDC 8/17/2011)