Nondestructive characterization of defects using a novel hybrid ultrasonic array sensor

The concept of a novel hybrid array transducer is introduced in this article. Based on the principles of dynamic beam steering and ultrasonic shadowing, a transducer consisting of an assembly of a linear phased array and a static array is developed. Using a dynamic pitch-catch configuration, the transducer is capable of determining the location, size and orientation of a planar defect without scanning or relocating the transducer. A theoretical shadow analysis carried out in this work allows for developing a scheme to characterize a single defect. To demonstrate the feasibility of the technique, a rail specimen with real defect has been assessed. This scheme proves to be a viable approach for characterizing transverse defects (TD) with good accuracy.