Patent ID: 8205785
Filing Date: 2012-06-26
Classification: B23K

Abstract:
1. A friction stir welding process, comprising: rotating a pin tool at a first constant speed in a first direction; rotating a shoulder tool at a second constant speed in a second direction, wherein the shoulder tool surrounds the pin tool; penetrating two work-pieces to be welded with a pin of the pin tool until a shoulder of the shoulder tool contacts a surface of the work-pieces; generating frictional heat to plasticize material of the work-pieces forming a continuous weld; reversing the first direction of the rotation of the pin while maintaining rotation of the shoulder tool in the second direction; and after reversing the first direction of the rotation of the pin tool, retracting the pin from the material while the shoulder tool maintains contact with the surface of the work pieces such that the pin retracts vertically.