A new approach for estimation of defects detection with infrared thermography

A new approach is proposed for a priori ascertaining the suitability of infrared thermography for the non-destructive evaluation purposes of materials. The novelty regards a cause/effect relationship between the thermal signature perceived by the infrared camera and a dimensionless group, which includes geometrical and thermal characteristics of the defect and host material. Such relationship, which was experimentally assessed through the evaluation of several specimens, is helpful to predict the thermal contrast associated with a type of defect embedded inside a certain material. This prediction of course is useful in decision making about the use of infrared thermography without preliminary feasibility tests and thus with economic benefits.