Characterization of Ceramics based on Laser Speckle Photometry

Advanced ceramic components are frequently used in industrial applications. As a brittle material, ceramic reacts very suddenly to excessively high stresses. Existing defects lead to rapid crack growth followed by spontaneous destruction. This leads to a functional failure of the entire component. It is therefore important to develop innovative techniques to ensure a good quality condition of ceramic products. Laser Speckle Photometry (LSP) is an optical non-destructive testing method. It is based on the dynamic analysis of time-resolved speckle patterns which are activated by an external excitation. In this paper, we will present two investigations on ceramic components using the LSP technique. One is the non-destructive stress characterization on ceramic surfaces and the other is the defect detection on ceramics components. The aim is to improve the quality and safety control of ceramic production in the challenging industrial field. Preliminary results have shown an extraordinary potential of the LSP sensor system for non-destructive characterization of ceramics in terms of stress monitoring and surface defect detection.