Weld flaw characterization through mathematical modeling from ultrasonic signal

Non-destructive testing (NDT) techniques are most commonly employed for detection and characterization of flaws in the component. Apart from flaw characteristics, another parameter which is equally important to assess the structural integrity of engineering components is the material property. Nondestructive testing techniques offer several advantages over the conventional coupon-based techniques. Ultrasonic Testing is one of the widely used NDT techniques for material characterization. In this paper flaw detection such as lack of fusion and slag of welding carbonized steel and stainless steel material is characterized using discrete wavelet transform (DWT).In order to categorize the type of flaws, the given ultrasonic signal is subjected into DWT decomposition. Then, energy is calculated from DWT approximation coefficient. Finally corresponding welding flaw is determined using computed energy.