Detecting surface and volume defects in metals by the laser-acoustic method

An all-purpose non-destructive method for detecting surface and volume defects in metallic objects has been developed. This technique is based on scanning the surface of a studied object with a focused laser beam and detecting the generated acoustic waves with a piezoelectric sensor. Defect control is performed by measuring the amplitude and propagation time of an acoustic signal to a detector, when the laser beam passes a defect zone.