Surface-breaking defect detection and characterization is a safety-critical non-destructive testing (NDT) process for many regulated industries, including railway networks, oil and gas, energy generation, aerospace, automotive, and civil infrastructure. There are several approaches in common use, ranging from relatively simple techniques such as visual inspection, dye penetrants, and magnetic particle imaging, to more sophisticated methods such as radiography, ultrasonic scanning and guided wave imaging. We have shown, through a Starting Grant, that non-contact generation and detection of surface waves can give benefits when characterising surface-breaking defects.
This project has developed a single measurement system for surface-breaking defect characterisation, giving an output of defect position and characteristics such as depth and propagation angle, de-skilling the testing process. The prototype has higher spatial resolution than previous laboratory measurements, and the sensors have been miniaturised, enabling easier scanning. They have been tested on samples removed from industry and shown to give an accurate measurement of defects of mm-dimensions.
