Influence of tool shoulder geometry on properties of friction stir welds in thin copper sheets

Abstract

a b s t r a c tThe aim of this work is to study the influence of the shoulder geometry on friction stir welding of 1 mmthick copper-DHP plates. The welds were produced using three different shoulder geometries, flat, conical and scrolled, and varying the rotation and traverse speeds of the tool. The flat shoulder tool proved to be inadequate for performing welds, because many defects were produced for all welding conditions. In turn, the scrolled shoulder tool is more effective than the conical one in the production of defect free welds. However, both geometries required a minimum rotational speed to avoid internal defects. For the same welding parameters, greater grain refinement, higher hardness and improved strength are also achieved in the nugget of the welds, using the scrolled tool.

Microstructure–property characteristics of a novel non-weld-thinning friction stir welding process of aluminum alloys

“…The concavity is designed to provide a reservoir of the pin sheared material. Scrolls are among the most useful geometrical features used for developing an inwardly-directed traction force under tool shoulder during FSW [20][21][22], therefore, three equally spaced scrolls were machined on the concave shoulder. The conical tool pin had right hand threads for counterclockwise rotation.…”

Effect of welding processes on mechanical and microstructural characteristics of high strength low alloy naval grade steel joints

“…Friction stir welding (FSW) is a novel solid state joining technique that is presently attracting significant attention on welding of hard metals such as steel and titanium [9][10][11].…”

Improving the structure-property of aluminum alloy friction stir weld by using a non-shoulder-plunge welding tool

“…The flowing plastic material is then contained and trapped in the space during welding. Scrolls are among the most useful geometrical features used for developing an inwardly directed traction force under tool shoulder during FSW [17][18][19]; therefore, three equally spaced scrolls were machined on the concave shoulder (see Fig. 2b), which prevents the plastic material under shoulder from slipping out during NSP-FSW.…”