Core Structure Formation in the Joints Fabricated by Friction Stir Welding of Metals with Polymorphic Transformations

Resumo

The microstructures of the weld core, the heat-deformation-affected zone, and the heat-affected zone having formed during the friction stir welding (FSW) of 12Kh18N10T steel and OT4-1 and VT-1 alloys are studied. The weld core of the solid-state FSW welded joints made of the metals and alloys that undergo polymorphic transformations is shown to form under structural superplasticity due to corporative recrystallization processes and phase transformations.