Patent ID: 7997472
Filing Date: 2011-08-16
Classification: B23K

Abstract:
1. A method of forming a friction stir weld between a magnesium-based alloy workpiece and an aluminum-based alloy workpiece, the method comprising: forming an assembly in which the magnesium-based alloy workpiece and the aluminum-based alloy workpiece have faying surfaces with a faying surfaces weld location at which the friction stir weld is to be formed and one of the workpieces has a surface with a friction stir engagement location for engagement with a rotating friction stir weld tool; placing an interlayer composition consisting essentially of adhesive, copper, tin, and zinc at the faying surfaces weld location; and friction stirring the magnesium-based alloy workpiece and the aluminum-based alloy workpiece with a friction stir tool that initially engages the friction stir engagement location and penetrates the workpieces to each faying surfaces weld location, in which the action of the friction stir tool causes mixing of the interlayer composition with metal elements of the magnesium-based alloy workpiece and the aluminum-based alloy workpiece and forms a weld material at the faying surfaces weld location, the weld material comprising constituents from the interlayer composition, each metal workpiece and any reacted products, and in which the action of the friction stir tool causes at least a portion of the adhesive to cure and to bond the magnesium-based alloy workpiece and the aluminum-based alloy workpiece together.