To apply straight-beam ultrasonic testing techniques to identify and characterize internal discontinuities in test specimens

To evaluate internal discontinuities in various specimens using the ultrasonic pulse-echo straight-beam contact testing method in accordance with ASTM E114-20

The experimental procedure involved systematic ultrasonic examinations of three distinct specimens: an assigned test block, a large rectangular block with six holes, and a square block with two legs

Prior to testing, both the NTL 2 (oscilloscope CRT) and DMS Go (DDR and CRT) ultrasonic instruments were calibrated

ASTM E114-20 guidelines were followed throughout the experiment to ensure consistent and reliable data acquisition

The assigned test block showed no detected defects, and all DDR dimension readings were consistent with no discrepancies

For the large rectangular block, readings for the third and fourth sections were out of specification due to larger, welded holes that produced stronger signals, and the transducer could not detect the last section's hole as it was too close to the surface and outside the detection range

The square block with two legs initially showed no DDR reading in the middle section due to a lack of a single strong returning signal; further investigation with the oscilloscope revealed numerous small discontinuities or defects that blocked a clear signal, indicating issues with the material in that section, and received a 100% report