Properties and structure of friction stir welded joints in 1424 and V-1461 (Al–Li) alloys^*

* Selected from Svarochnoe Proizvodstvo 2017(4) 22–26

Abstract

The effect of the friction stir welding (FSW) conditions on the structure of welded joint and mechanical properties of 1424 and V-1461 alloys is investigated. FSW is accompanied by the formation of a recrystallized fine-grain microstructure in the welded joint. It is shown that the increase of the heat input to the welded sheets does not increase the average grain size in the weld zone (the average grain size is 1.5–2.2 μm). The tensile strength of the welded joints depends on the welding conditions for both alloys. Special features of the microstructure formed in the zone of the welded joint are discussed and the effect of the microstructure on the mechanical properties of the welded joints and evolution under the effect of heat treatment after FSW are determined.

Keywords:

• Aluminium alloys
• friction stir welding
• fine-grained structure
• dynamic recrystallization
• strength

Notes

* Selected from Svarochnoe Proizvodstvo 2017(4) 22–26