This zero detection is due to straight notches and not to wave scattering differences of materials. The TW sizings are accurate and not spread. TW sizing is also good. These good results are due to the low scattering of ultrasonic beam by the material. For this analysis, only the results provided by the testing of specimens SMT 1 and 2 are taken into account, because the good properties of the materials of SMT 3 and 4 made all their notches obviously fully detectable.
Tilted notches are better detectable on one side, due to the wide interface for the beam.
In contrary, straight notches are seen with the same FDF and amplitude on each side, which was expected. Also for tilted notches, as expected, it was found that FDF and amplitude increased with the notch height. In graph 6, the analysis is made taking separately into account both the angle and the height of the notches. The intention of this project is to improve ultrasonic examination procedures for austenitic stainless steel welds. Automated and manual ultrasonic inspection was carried out by the three industrial partners on the test specimens representing the four groups of stainless steel under investigation in this study.