What does "multi-frequency testing" involve in the context of PAUT?

Multi-frequency testing in the context of Phased Array Ultrasonic Testing (PAUT) involves utilizing different frequencies during the inspection process. This approach optimizes defect detection by tailoring the frequency used based on the material properties being evaluated. Different frequencies interact with materials in various ways, affecting the depth of penetration and sensitivity to specific types of flaws. Hence, by adjusting the frequency, inspectors can achieve more effective detection of defects such as cracks, voids, or inclusions that may vary in size, orientation, and material composition.

Using this technique helps maximize the efficiency and reliability of inspections by enabling the examination of a wider range of flaws and conditions. Each frequency used in the inspection can yield distinct information about the material and its integrity, making this a crucial practice within PAUT applications.