What is the main reason for using dual-element transducers in Ultrasonic Testing?

Dual-element transducers are specifically designed to enhance the effectiveness of ultrasonic testing by separating the sending and receiving functions of the transducer. This design allows for improved sensitivity and resolution when detecting flaws in materials.

When a single-element transducer generates ultrasonic waves, it must also be responsible for receiving the echoes reflected back from the material under test. This dual responsibility can limit the quality of both functions, potentially leading to interference or reduced clarity in the received signals. By employing separate elements for sending and receiving, dual-element transducers can operate more efficiently. The transmit element can generate a powerful wave without the constraints of also needing to pick up echoes, while the receive element can be finely tuned to optimize its sensitivity for capturing reflected signals, thus resulting in a clearer and more accurate representation of the material's internal structure.

This capability to differentiate and fine-tune each function not only aids in better flaw detection but also improves overall measurement accuracy and reliability, which is critical in NDT applications.