Friction stir welding of V95 alloy of the Al–Zn–Mg–Cu system strengthened by heat treatment

Abstract

Results of investigations into the mechanical and corrosion properties and structure of friction stir welded joints in V95 alloy of the Al–Zn–Mg–Cu system are presented. It is shown that friction stir welding produces high-strength high-quality welded joints in welding of the ‘unweldable’ alloy, and the properties are determined by the condition of the heat-affected zone. It is also shown that a non-recrystallized structure forms in the core of the welded joints and the most probable mechanism of the formation of the ultrafine-grained equiaxed structure is collective dynamic polygonization and not dynamic recrystallization.

Keywords::

• FSW
• weld
• nugget
• strength corrosion
• structure
• polygonization
• recrystallization