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Glossary

time-of-flight diffraction (TOFD)

An advanced ultrasonic testing technique used for non-destructive evaluation and flaw detection in materials and structures. It is particularly effective for detecting and sizing cracks, discontinuities, and other defects in welded joints.

TOFD is based on the measurement of diffracted ultrasound waves that are produced when a sound wave encounters a crack or a defect in a material. The diffracted waves provide valuable information about the size, shape, and location of the defect. The diffracted signals are then received by sensors or transducers and analyzed.

TOFD typically involves the use of two ultrasonic probes positioned on opposite sides of the area being inspected. One probe emits an ultrasonic pulse, which propagates through the material, while the other probe receives the diffracted waves.