Defect detection in friction stir welding process through characterization of signals by fractal dimension

An attempt has been made in this investigation to explore the possibility of quantifying the dynamic spectrum of signals in friction stir welding process using the concept of fractal dimension. A series of scan with a fixed span of time signals is characterized by computed fractal dimension. Difference observed in the computed fractal dimension for defective welding condition. The factual change in fractal dimension is indicative the initiation of defect for a specific welding condition. The analysis reveals the fact that fractal dimension can be an independent indicator for the prediction of defect formation in friction stir welding process.