The Impact of Shoulder Diameter on the Mechanical Properties of Friction Stir Welding Joints in AA1100 Plate

Aluminium is becoming a popular construction material due to its strength, low density, and corrosion resistance. The fusion welding procedure is widely utilized, although it can cause problems like as slag inclusions and porosity. Friction stir welding (FSW) improves joint microstructure and strength, but it is difficult to utilize in thick materials due to the constraints of welding heat and stirring with traditional tools that can be a source of defect formation. In order to enhance the application of friction stir welding (FSW) on thick materials, this work presents bobbin tool friction stir welding (BTFSW). BTFSW testing on AA1100 aluminium yields joints of various properties. Various characteristics can affect the mechanical properties of the joint such as travel speed, tilt angle, plunge depth, and shoulder diameter. Shoulder diameter has a substantial influence on mechanical properties, hence this study concentrates on it. The results showed that the variation in shoulder diameter affected the joint’s tensile strength. The highest tensile strength of 120 MPa was obtained at a shoulder diameter of 16 mm meanwhile the lowest one of 107 MPa was obtained at a shoulder diameter of 22 mm. However, increasing shoulder diameter increased material defects.