Thermography can be classified in passive and active techniques. Active thermography is based on forced excitation of the conductive heat flow in a component. In contrast to flawless specimens, flawed joints show variations in the heat flow; this can be detected by transient surface temperature contrasts. Differences in heat images (recorded with infrared cameras) of flawed and flawless specimens are used for the evaluation. Today's automotive engineering increasingly demands state-of-the-art quality control. In order to assure their quality, components have to be inspected - ideally by means of non-destructive tests. However, many test cases do not offer reliable and automated non-destructive testing methods. Active thermography offers solutions to assure joint quality. This relatively new non-destructive evaluation method for materials and components is robust, contactless and two-dimensional. This paper provides an overview on the physical properties of the different investigated thermographic technologies: ultrasound, inductive and optical excitation of heat flows. By demonstrating the various test cases, by testing structural and elastic adhesives, mechanical clinch joints and laser-welded joints, the possibilities of respective excitation methods were discussed and examples of the results were demonstrated. Furthermore, the aspects of quality rating and automated testing were reflected.
Active thermography for quality assurance of joints in automobile manufacturing
Welding in the World ; 55 , 7/8 ; 90-97
2011
8 Seiten, 6 Bilder, 13 Quellen
Aufsatz (Zeitschrift)
Englisch
Application of pulsed thermography to quality assurance of thermal barrier coatings
SAGE Publications | 2012
|Application of pulsed thermography to quality assurance of thermal barrier coatings
Online Contents | 2012
|NTRS
|Quality assurance for common sense manufacturing
Emerald Group Publishing | 2002