Materials Science Forum, Vol.524-525, 471-476, 2006
Laser photoacoustic microscopy of mechanical stresses in modern ceramics and metals
The photoacoustic piezoelectric images of Vickers indented silicon nitride, Al2O3-SiC-TiC composite ceramic, nanonickel and nanocopper in unloaded and loaded states are presented. It is demonstrated the influence of mechanical stresses on the photoacoustic images of Vickers indented areas both for ceramics and metals. For Al2O3-SiC-TiC composite ceramic it is also shown that an increase of annealing time is accompanied by the decrease in the photoacoustic response from the radial crack tips. The obtained photoacoustic experimental results are explained within the framework of the model for the photoacoustic effect in stressed solids proposed by us earlier.