Time-of-Flight Diffraction
Time-of-flight diffraction is a highly sensitive ultrasonic method for flaw sizing that evaluates the diffraction of sound waves at the edges of cracks or defects.
Physical-Chemical Mechanism of Action
The method uses ultrasonic waves that are guided through metal. These waves are diffracted at the edges of cracks or defects and sent back. The time it takes for the signal to reach the receiver (time-of-flight) is measured.
Metallurgical Relevance & Risks in Welding
Time-of-flight diffraction is especially useful for precisely determining the size and location of cracks in weld areas. It can also be used to check the quality of the structure and ensure that there are no unwanted phases or deformations. Incorrect interpretation can lead to missed or extra cracks, which poses risks to the safety and service life of the components.
Workshop Practice & Action Instructions
To use time-of-flight diffraction, you need an ultrasonic device with special sensors. Direct the sound waves at the area to be inspected and measure the time of flight of the waves. The data is then transferred to a computer for evaluation. Make sure the device is properly calibrated and measurements are taken in a quiet environment to get accurate results.