What does the term "S-scan" refer to in PAUT?

The term "S-scan" in Phased Array Ultrasonic Testing (PAUT) specifically refers to a display that visualizes depth or amplitude variations from ultrasound signals. This type of scan provides a two-dimensional graphical representation, where one axis typically represents depth while the other axis shows the amplitude of the received signals. The S-scan format is particularly useful for interpreting the characteristics of flaws or discontinuities within a material, allowing inspectors to identify the size and location of defects more effectively.

The emphasis on visualizing both depth and amplitude makes the S-scan particularly valuable in providing a clear and immediate understanding of the subsurface condition of the material being tested. This representation enhances the ability of technicians to draw conclusions about the integrity and quality of the material based on the ultrasonic data collected during testing.