Photoacoustic microscopy of ceramic bending specimen

A Photoacoustic Microscope was used to investigate surface and subsurface areas of ceramic bending specimens with artificial flaws. After this the samples were broken in a four-point-bending test. The comparison of the results of the fracture specification and the results of the nondestructive evaluation shows that a large fraction of the flaws causing the fractures were detected. We try to explain why the other part of the flaws causing the fractures could not be detected, and we give a quantitative evaluation of the detection probability for defects using photoacoustic phase images.