What does “resolution” signify in phased array ultrasonic testing?

In phased array ultrasonic testing, "resolution" refers to the ability to distinguish closely spaced flaws within a material. This concept is crucial because, in many inspection scenarios, it is necessary to differentiate between defects that might be located very near to each other in order to assess the integrity of a component accurately. High-resolution capability allows inspectors to identify whether two similar signals correspond to separate flaws or if they are part of a single defect.

The resolution in this context is influenced by several factors, including the bandwidth of the ultrasonic waves used and the focusing capabilities of the phased array probes. A system with good resolution can provide clear and distinct images of these closely grouped defects, which is essential for making informed decisions about repair or replacement.

While resolving the ability to inspect thicker materials, the range of depths tested, or the effectiveness of color mapping are relevant factors in testing, they do not directly pertain to the concept of resolution as it is used in the context of flaw detection and identification. These aspects relate more to the overall capabilities and functionalities of ultrasonic testing rather than the specific ability to resolve closely spaced flaws.