What is the purpose of the time-of-flight diffraction (TOFD) method?

The time-of-flight diffraction (TOFD) method is specifically designed for measuring the time it takes for ultrasonic waves to travel to a flaw and reflect back. This technique uses the time intervals between the emitted and received signals to ascertain the depth and shape of the detected flaws. By analyzing these time intervals, TOFD provides a unique way to identify and characterize flaws in materials, particularly in welds.

This method is advantageous because it yields precise measurements of flaw sizes and depths, allowing for accurate assessments of a component's structural integrity. By focusing on the reflection and travel time of ultrasonic waves, technicians can gather important data that informs repair or maintenance decisions, thereby enhancing the overall reliability of inspections.