Patent ID: 7597237
Filing Date: 2009-10-06
Classification: B23K

Abstract:
1. A process of solid-state welding using a welding apparatus with a head, the head including a ring-shaped rotatable shoulder, a first pin and a second pin, both pins extending downwardly relative to the shoulder and not integrally connected to the shoulder, the process comprising: coupling a first workpiece to a table; coupling a second workpiece to the table and against the first workpiece to form an interface between the first workpiece and the second workpiece, the interface defining an X direction, wherein a Y direction is perpendicular to the X direction and parallel to the plane of table, and a Z direction is defined as perpendicular to the plane of the table; rotating each of the first pin and the second pin about a separate, spaced non-parallel axis of rotation with a gap defined therebetween, the axes of the first and second pins being inclined toward each other to intensify the shear strain of the interface within the gap; rotating the ring-shaped shoulder disposed about the first and second pins relative to the first and second pins in their entirety, the pins rotating about non-parallel axes of rotation relative to the shoulder with the ring-shaped shoulder bearing downwardly against the first and second workpieces; moving the head along the interface, with the shoulder bearing downwardly against the first and second workpieces and the first and second pin disposed in the first and second workpieces; and directing the first pin and the second pin repeatedly across the interface in a back and forth stitching motion between the first and second workpieces to form a solid state weld between the first and second workpiece.