The influence of the Friction Stir Welding process on the non-heat-hardenable aluminum alloy AA5056 structure formation depending on the sheet workpiece rolling direction

Abstract

This paper is devoted to the study of friction stir welded joints made of 5-mm-thick aluminium alloy AA5056 sheet metal. These joints were produced using workpieces cut along and across the rolling direction of the material. Metallographic studies were carried out to determine the structural features of joints obtained by friction stir welding. Tensile tests across the weld were carried out to verify that the ultimate tensile strength requirements for the welded joint are met. It was found out that mechanical properties of joints are different depending on the rolling direction. In the case of welding along the rolling direction with varying parameters, a large number of welds have an ultimate tensile strength of at least 0.9 of the base metal one. In the case of welding across the rolling direction, in some cases the ultimate tensile strength of the weld exceeds that of the base metal. As a result of the research, it was found that when welding in different directions relative to the rolling direction, there is a wide range of friction stir welding parameters for 5-mm-thick workpieces made of AA5056 alloy, which also depends on the rolling direction of workpieces.

Improving the quality and efficiency of friction stir welding of aluminum alloy plates

“…[2] FSW has found application in aircraft and rocket building, shipbuilding, automotive and car building. FSW is most effective when welding large-sized parts made of aluminum alloys, since: welding can be carried out at a sufficiently high speed, which has been proven by researchers AG Boytsov, VV Kachko and DN Kuritsyn [3]; the strength of the joints can reach a strength close to that of the base material [4]; there is practically no tool wear under optimal conditions; welding temperature does not exceed 500 °C, which allows the use of alloy steel tools. These products include the tanks of carrier rockets, for example, tanks of fuel and oxidizer "Proton-K", which are made of AMg6 alloy.…”