Metallurgical and Mechanical Study of Dissimilar Friction Stir Welding of Carbon Steel and Stainless Steel

Friction Stir Welding (FSW) is a solid-state thermomechanical joining process. FSW
capable in joining similar and dissimilar materials without reaching the melting point of
the materials. These recognized advantages of solid-state joining have led to attempts to
use FSW for wide range of alloys. FSW has becoming the techniques of choice in
joining similar and dissimilar soft related materials such as aluminum, magnesium and
more which gives advantages to the aerospace, automobile and ship building industries.
However, it has not been utilized in Oil and Gas industry and energy industry for
welding of hard and dense materials such as carbon steel and stainless steel. The overall
aim of this study is to investigate the metallurgical and mechanical properties of
dissimilar FSW between carbon steel and stainless steel. This can be done by evaluating
the microstructure formation on the weld section of stir zone (SZ), thermal mechanical
affected zone (TMAZ), heat affected zone (HAZ) and their effects on the mechanical
properties of the joint.