What is the frequency range commonly used in ultrasonic testing?

The frequency range commonly used in ultrasonic testing is between 0.5 MHz and 15 MHz. This range is ideal for detecting flaws in various materials and provides a balance between penetration depth and resolution. Lower frequencies (closer to 0.5 MHz) are capable of penetrating thicker materials and are often used in applications such as weld inspections or examining structural components. Conversely, higher frequencies (up to 15 MHz) enable better resolution, making them suitable for detecting smaller defects but with reduced penetration depth.

Frequencies outside this range, such as those below 0.5 MHz or above 15 MHz, can present limitations. Lower frequencies might not provide sufficient resolution for tiny defects, and very high frequencies could have limited effectiveness in penetrating thick materials, which may be necessary in certain applications. Thus, the selected frequency range is critical in ensuring effective ultrasonic testing.