Material characterization and damage detection in layered media through the Ultrasonic Polar scan.

Non-destructive testing (NDT) refers to techniques used in the life cycle of a structural part of their quality, functionality and 'health' testing without destroying the object, nor affecting its properties. The development of NDT techniques is constantly evolving and needs continuous improvement due to the emergence of new industrial materials, the increasing demand for more sensitive and more quantitative characterization and quality control, and the need for early detection of defects. The implementation of a suitable NDT system can save lives, time and costs. The Ultrasonic Polar Scan (UPS) is an advanced NDT method that analyzes reflected or transmitted ultrasonic signals for a variety of azimuthal and polar angles. The recorded information (amplitude, phase or time-of-flight) is a fingerprint of the local material properties. The project aims to expand the current UPS on three levels: 1) inverse determination of the actual material properties (stiffness, damping, layers, orientation) for multi-layer composites 2) design of linearity-based UPS delaminations and micro-cracks to inspect and 3) practical redesign of obtain an efficient inspection tool during the laboratory setup. The goal is to quantify material parameters with an accuracy better than currently reachable, to identify damage with dimensions less than a millimeter, and to speed up the UPS recording acceptable times.