A quantitative study of TFM-like imaging techniques for nondestructive evaluation

Braconnier, D.; The Phased Array Company; USA

Braconnier, D.; The Phased Array Company; USA
Carcreff, E.; The Phased Array Company; USA
Laroche, N.; The Phased Array Company; USA
Xu, Z.; The Phased Array Company; USA

ID: ECNDT-0399-2018
Session: PAUT & TFM 1
Room: G2
Date: 2018-06-11
Time: 13:30 - 13:50

Full Matrix Capture (FMC) and the Total Focusing Method (TFM) are revolutionizing phased array ultrasound. FMC and TFM are a family of advanced acquisition and post-processing techniques, respectively, and can be implemented real-time for inspection purposes. FMC/TFM provides many benefits over conventional Phased Array, with unique features, such as: a real-time high resolution reconstruction grid, viewing of several wave modes from one setup, improved axial and lateral resolutions, improved flaw characterization and sizing, and reduced misinterpretation of geometric echoes versus defects. FMC data can be saved to be reprocessed later with improved signal processing algorithms. This paper will present a fundamental detailing of FMC/TFM variety of processing, a sampling of TFM images from real-world defects, as well as highlighting improvements to speed up and optimize both FMC and TFM while keeping, and in some cases, improving signal-to-noise ratio. We also address the variable inputs to a system that can have a great overall effect on the FMC/TFM inspection and data quality. Although FMC requires large amounts of data to compute a TFM image, the instrument used for the experiments has more than enough data transfer capability. Furthermore, with the acquisition instrument’s small form factor, advanced high resolution imaging capabilities that were once only lab capable can now be industrialized and even automated using scanners and robots.