A kind of double shoulder friction stir welding method

Abstract

The invention discloses a double-shoulder friction stir welding method, which mainly comprises moving a lower shaft shoulder and a rotary rod to a welding point, the upper end face of the lower shaft shoulder is closely attached to the back of the material to be welded, and the upper shaft shoulder and stirring The needles move together to the top of the starting point, rotate at the set speed and approach the upper surface of the material to be welded, wherein the stirring needle rotates and penetrates into the material to be welded, and all penetrates the material to be welded, and begins to weld to After the operation is completed, it enters the withdrawal operation stage, and the rotating rod and the stirring needle are pulled out of the inner hole of the lower shaft shoulder at the same speed until the upper end face of the rotating rod and the upper end face of the lower shaft shoulder are flush, and the stirring needle continues to move. The set linear speed moves upward, the rotating rod and the lower shoulder rotate at a reduced speed, while the stirring needle and the upper shoulder continue to move forward, the stirring needle continues to move upward to realize the retraction movement until all the stirring needles are withdrawn into the upper shoulder. , so as to realize the retraction of the stirring needle during the double-shoulder friction stir welding process, and realize no keyhole after welding.

Description

technical field [0001] The invention relates to the technical field of welding, in particular to a double-shoulder friction stir welding method. Background technique [0002] Friction stir welding is a revolutionary solid-state joining technology invented by the British Welding Institute (TWI) in 1991. During the welding process, the material to be welded is plasticized under the action of the rotating frictional heat of the stirring head, and is stirred during the welding process. A dense weld is formed under the extrusion and driving action of the head. [0003] Double shoulder friction stir welding is a new connection technology developed on the basis of friction stir welding. The self-supporting effect of the lower shoulder during the welding process eliminates the need for back support during the welding process, breaking through the structure of friction stir welding. The form is limited, and the weld does not have the problem of incomplete penetration of the back, an...

AI Technical Summary

Problems solved by technology

In these areas where the stirring tool is stopped and then restarted, it is difficult to guarantee the connection quality of the weld seam, and welding defects are easily generated, which will seriously cause the entire weld seam to be scrapped, and after the lower shoulder is removed, an additional backing plate is required to Keep welding going on, which is not conducive to automatic production

In short, the interruption of production rhythm will have a very adverse impact on product quality and production efficiency