On Friction Stir Welding of Mg-Zn-RE-Zr Alloy Using Threaded Tools for Aerospace Application

Magnesium alloys are widely used for manufacturing aerospace engineering components due to their light weight, excellent high temperature properties and corrosion resistance. In the present investigation, Friction Stir Welding (FSW) has been investigated as a solid state joining method for Mg-Zn-RE-Zr cast alloy. The Mg-Zn-RE-Zr alloy (commonly known as RZ-5) of 6 mm thickness was fabricated by sand casting method in an aeronautical engineering component manufacturing environment. The cast Mg-Zn-RE-Zr alloy plates were then joined using FSW process by utilizing in-house developed tools with cylindrical threaded pin profiles and shoulder surface geometries. The effects of FSW process parameters such as rotational speed and welding traverse speed on the cast Mg-Zn-RE-Zr alloy welds were investigated. The tensile strength, percentage elongation, hardness and microstructure of the cast Mg-Zn-RE-Zr alloy welds were also investigated.