Application of Selective Heating in Al-Steel Dissimilar Joining
Al-steel dissimilar joining has the advantages of both the materials in a single unit. This combination of materials has high industrial applicability. There is a large difference in physical, thermal and metallurgical properties of both the materials, which makes it difficult to join combination. In present work, the solid state joining of commercially pure aluminum and steel was performed. A number of attempts have been reported in the literature regarding preheating of steel to achieve better weld amalgamation. Earlier approaches were not much effective due to wide-spreading of heat in both plates. Thus, in this work, selective heating of steel side was performed using an induction heating equipment to avoid the heating of the aluminum side. Further, weld joints made by conventional friction stir welding (FSW) and newly developed induction heat-assisted FSW (IHAFSW) were compared using tensile testing and micrograph analysis. It was found that the elongation is improved up to 35% in hybrid welding which was a major concern in FSW. Detached debris of steel was alleviated and bonding surface area was increased in selective preheating which suggest higher ductility and in a sound weld joint.
Keywords— Deformation, Friction stir welding(FSW), Hybrid joining, Induction heating, Intermetallic, solid welding, Unconventional.