Nondestructive Inspection in Depth of Welding by Nonlinear Ultrasonic Test

Abstract

A nondestructive evaluation method for delineating the solidification boundaries of arc weld in thin steel plate is developed by using a nonlinear ultrasonic imaging technique. With the nonlinear ultrasonic technique, the higher harmonic amplitudes at solidification boundaries appear high. The estimated solidification boundaries are close to the contour line obtained by the conventional macro photographs. Thus, the conventional destructive observation of the depth of welding could be replaced by the nonlinear ultrasonic imaging technique.