Ultrasonic flaw imaging by the FSAP technique using array transducer for angle beam testing

There is a phased array technique which makes use of flaw echoes, measured by every two-element combination as a pulser and a receiver, to synthesize high amplitude beams for any arbitrary angle and/or focal depth. Using this full waveform sampling and processing (FSAP) technique, we show a flaw reconstruction method for the angle beam phased array ultrasonic testing. In the case of the angle beam testing, it is necessary to estimate a beam path from a wedge to a specimen appropriately and to consider the mode conversion at the wedge-specimen interface. The main feature of our method is the use of processed wave data, called "scattering amplitude", which is extracted from each flaw echo. First, the basic principle of the reconstruction method is described and then some flaw reconstructions are demonstrated. The resolution of the flaw images and the accuracy of flaw sizing can be improved by means of the scattering amplitude.