Method and apparatus for phased array based ultrasonic evaluation of rail

A testing apparatus for detecting defects in a rail, the testing apparatus comprising:

• a carrier structure configured to travel in a direction generally parallel to a longitudinal axis of the rail;
• a first set of phased array transducer elements coupled to the carrier structure and configured to generate ultrasonic signals, wherein the first set of phased array transducer elements are excitable in an activation pattern that temporally progresses in the direction of travel or in a direction opposite the direction of travel;
• and
• a second set of transducer elements coupled to the carrier structure and configured to receive the generated ultrasonic signals.

A method for testing material integrity of an object, the method comprising:

• controlling a first aperture dynamically to transmit a first set of ultrasonic signals;
• transmitting the first set of ultrasonic signals towards a region of interest via the first aperture;
• controlling a second aperture dynamically to receive a second set of ultrasonic signals;
• and
• receiving the second set of ultrasonic signals from the region of interest via a second aperture.

A method for detecting a defect in a rail having a longitudinal axis, the method comprising:

• providing a phased array transducer having a plurality of ultrasonic transducer elements that are disposed in a housing;
• exciting a first ultrasonic transducer element to transmit an ultrasonic signal towards a region of interest;
• and
• detecting receipt of the ultrasonic signal from the region of interest at a second transducer element located at a distance behind the first ultrasonic transducer element, the distance being measured in a direction of the longitudinal axis of the rail.

A testing apparatus for detecting defects in a rail, the testing apparatus comprising:

• means for dynamically controlling a first aperture for transmitting a first set of ultrasonic signals towards the rail;
• means for transmitting the first set of ultrasonic signals into the rail;
• means for dynamically controlling a second aperture for receiving a second set of ultrasonic signals from the rail;
• and
• means for receiving the second set of ultrasonic signals from the rail in response to the first set of ultrasonic signals.