Automated System for Crack Detection using Infrared Thermographic Testing

Abstract

The objective of this study was the development of the automated system for crack detection on square steel bars used in the automative industry. The automated system for thermographic crack detection uses brief pulsed eddy curr-ents to heat steel components under inspection. Crack, if present, will disturb the current flow and so generate changes in the temperature profile in the crack area. These changes of temperature are visualized using an infrared camera. The image acquired by infrared camera is evaluated through an image processing system. The advan-tages afforede by the system are its inspection times, its excellent flaw detection sensitivity and its ability to detect hidden, subsurface, cracks. The system is part of the inspection line where the subsurface and surface cracks are searched. The system is fully automated and its ability is to evaluate four meter blocks within 20 seconds. This is the unique reason for using this system in real industrial applications.