Method and circuit arrangement for disturbance-free examination of objects by means of ultrasonic waves

A method for the non-destructive examination of a contour of an object by processing signal waves which are generated by reflection of ultrasonic waves at defect locations of the structure of the object, comprising the steps of:

• emitting a complete wave front onto the at least one contour of the object to be examined by means of a plurality of independent transmitter elements;
• receiving a wave reflected by the structure of the object by means of a plurality of receiver elements. which are independent of one another;
• digitalizing the signals received from the receiver elements;
• storing the digitalized signals according to amplitude and propagation time in a storage element;
• recording and storing the contour of a surface of the object to be examined;
• and
• controlling the independent transmitter elements are controlled in a time-delayed manner such that the emanating wave front extends substantially parallel to the contour of the surface of the object and waves reflected by the object are received in a time-delayed manner and generate a substantially planar interference pattern.

A circuit arrangement for processing signals which are generated during non-destructive examination of objects by reflection of ultrasonic waves at defect locations of the structure of the object, comprising:

• a signal recording unit with a pulse generator for actuating transmitter/receiver elements for emitting a complete wave front and for switching the transmitter/receiver elements to receive, the transmitter/receiver elements constituting a probe;
• a multiplexer via which analog signals applied to the receiver elements can be transmitted to AID converters, and
• a storage element to which outputs of converters are connected for storing digitalized signals,
• wherein the storage element includes means for storing the digitalized signals with respect to their signal amplitude and propagation time and
• a summing element for the phase-locked addition of the amplitude values stored in the storage element is arranged in tandem behind the storage element and a signal which can be evaluated with respect to the defect location is applied to an output of the summing element.