Abstract: A method for testing a component non-destructively, particularly for internal defects, includes the following steps: a) providing a rotationally symmetrical component having a plurality of preferably cylindrical recesses, which are arranged at one or more hole circles, b) arranging a transmitter probe serving as an ultrasound transmitter and a receiver probe serving as an ultrasound receiver spaced apart from each other outside the component such that ultrasound waves can be irradiated into a shaded area located behind one of the recesses in the component by the transmitter probe and ultrasound waves which are diffracted at least at one defect present in the shaded area can be received by the receiver probe, and c) using time of flight to determine whether one or more faults are present in the shaded area. An apparatus carries out such a method.

Abstract: A method for testing a component non-destructively, particularly for internal defects, includes the following steps: a) providing a rotationally symmetrical component having a plurality of preferably cylindrical recesses, which are arranged at one or more hole circles, b) arranging a transmitter probe serving as an ultrasound transmitter and a receiver probe serving as an ultrasound receiver spaced apart from each other outside the component such that ultrasound waves can be irradiated into a shaded area located behind one of the recesses in the component by the transmitter probe and ultrasound waves which are diffracted at least at one defect present in the shaded area can be received by the receiver probe, and c) using time of flight to determine whether one or more faults are present in the shaded area. An apparatus carries out such a method.