Ultrasonic Characterization of Rough Cracks

It has been reported before that frequency and angular information from ultrasonic scattering can be used to characterize smooth artificial defects in metals. In this study ultrasonic measurements from fractured and smooth penny-shaped cracks of the same size were carried out. Experimental procedures included the use of broad band and narrow band ultrasonic signals. From angular and frequency dependence of ultrasonic scattering measurements the size, shape, orientation and rms roughness of the fractured surface have been estimated. Ultrasonic measurements of these parameters have been compared to the actual parameters of the defect