The ideal Non Destructive Evaluation/Examination process should be carried out using a fully automated system: planning, execution, evaluation and reporting would be all tasks performed by automated technologies and artificial intelligence that don’t need human intervention, thus taking the Human Factor out of the equation. Not yet reaching this level of automation, it is still possible to improve the overall quality of the NDE process to increase both speed and quality, while maintaining safety.
Ultrasonic Testing NDE is considered a safe, portable and reliable inspection method. Detection and characterization depends upon factors like technician’s experience and skills, especially for shear wave UT, where an amplitude vs time signal, the A-Scan, is the only given information from the specimen to be examined. With this technique there is very little digital data saved, often in the form of screenshots.
The evolution of shear wave UT was represented by the use of an array probe with the Phased Array technique: the new capabilities of simultaneously steering the beam in multiple directions and combining all the A-Scans in images together, has made it easier to interpret any anomalies found during inspection.
However, skill and experience are still very important factors to avoid false positive and false negative results. For example, focusing distance from the array probe and false signals from mode conversion may lead to the wrong conclusions.
Ultrasonic imaging technology based on full matrix capture has the intrinsic ability to improve interpretation over more conventional techniques such as PA UT or shear wave UT since it provides information not only about the size of flaws, but also on their geometry in terms of horizontal and vertical extent.