Experimental and Numerical Wear Characterization by Means of Active Thermography Technique

Thermography is a non-contact technique used to obtain thermal maps of a component surface. Active Thermography (AT) has gained a lot of interest in recent years as a tool to characterize thermal properties and fatigue damage in materials, coatings, and components. Hidden flaws can also be detected based on the surface thermal map in a non-destructive way . This paper presents a preliminary experimental procedure where Lock-in AT is exploited to characterize wear damages of a flat steel surface featuring a series of linear wear traces from pin-on-flat wear tests. A dedicated temperature data processing route was set up to correlate thermal signals to the characteristic parameters which may identify the amount of material loss by wear. The results suggest that AT may be a promising, fast, and alternative method to detect and quantify wear on surfaces. An exponential law correlates the wear track width, depth, and area with the intensity peaks of the fundamental harmonics of the pulsed thermal response. Although the sensitivity and reliability of this method is still to be assessed, this preliminary work might pave the way to significant implications for AT in industry in the case of wear on hidden surfaces.