Application of Infrared Thermography in Bobbin Friction Stir Welding–Exploring a New Dimension

Friction stir welding (FSW) is a known process widely used for different metals, metal alloys and composites. The process is widely used in marine, automobile, railway and aerospace industries. The weld quality depends on tool design. Frictional heat is the main factor governing weld quality. Measurement of this developed heat or temperature during FSW is very difficult. Such measurements and thermal analysis of the weldments is very lean in literature. Researchers have used thermocouples for direct temperature measurement. Infrared (IR) thermography, a technique widely used for preventive maintenance in industries, will be an upcoming technology one can use fruitfully in metal joining. Quality of the weld joint is dependent on the generation of frictional heat during the welding. Measurement of the heat or temperature during welding is a big issue. Again the measurement of temperature of tool in running condition is another issue to be thought of. The present paper will be a flashlight in applying a new concept of IR Thermal imaging for testing and thermal analysis. The technique was adopted by the author to know its utility for FS Welding. The IR Thermography was carried out using IR imager. It was found to have a great potential in adapting the IR Thermography for friction stir welding experiments. The experiment was carried out using fixed gap bobbin tool for welding AA6082 T6 Al alloy in butt configuration. Characterization of the welded samples showed better results of the experiment with zero defect.