Total Focusing Method (TFM)

TFM is an advanced ultrasonic imaging technique that post-processes Full Matrix Capture (FMC) data to synthetically focus the beam at every pixel in the region of interest, producing high-resolution images of complex defects.

Definition

The Total Focusing Method (TFM) reconstructs an ultrasonic image by post-processing FMC data so that every pixel in the inspection grid is the focal point of a synthetically focused beam. The result is uniform resolution across the imaged volume — superior to conventional PAUT S-scans, which focus at only one depth.

Technical Context

TFM modes can use direct longitudinal, half-skip, full-skip, and mode-converted paths to image complex weld geometries. Code acceptance is recent: ASME Section V Article 4 Mandatory Appendix XI provides TFM rules.

When It Is Used

Critical weld inspection (austenitic, dissimilar metal)
High-temperature hydrogen attack (HTHA) detection
Crack-tip characterization in fitness-for-service

Related terms

Full Matrix Capture (FMC) — FMC is an ultrasonic data acquisition mode in which every element of a phased-array probe transmits in turn while all elements receive, producing a complete matrix of A-scans that can be post-processed using TFM and other algorithms.
Phased Array Ultrasonic Testing (PAUT) — PAUT is an advanced ultrasonic technique using a multi-element transducer (16–256 elements) with electronic beam steering and focusing, producing sectorial, linear, and compound scans for superior weld inspection and defect characterization.
Ultrasonic Testing (UT) — Ultrasonic Testing (UT) is an NDT method that uses high-frequency sound waves (typically 0.5–25 MHz) to detect internal flaws and measure thickness in metals, plastics, and composites by analyzing reflected echoes from a transducer.

More method terms

Radiographic Testing · Magnetic Particle Testing · Penetrant Testing · Eddy Current Testing · Visual Testing · Acoustic Emission Testing · Leak Testing · Thermography / Infrared Testing · Microwave Testing · Time-of-Flight Diffraction

Where this comes up in practice

Terms like this one appear in three places that matter commercially: the written practice that governs how your personnel are qualified, the procedures and technique sheets that define how an examination is actually performed, and the evidence an auditor or client asks for when they want to know why an inspection was accepted. Getting the terminology right is the easy part; being able to produce the qualification record, the calibration traceability and the procedure revision that applied on the day of the inspection is the part that decides audits.

Atlantis NDT provides NDT training and certification against ASNT SNT-TC-1A and ISO 9712, ASNT Level III consulting for written practices and procedure approval, inspection management software that holds qualification, calibration and procedure-revision evidence in recoverable form, and an asset integrity platform that binds inspection results to the asset they describe. Browse the full NDT glossary or ask a Level III directly.