Photoacoustic microscopy of indentation lateral cracks

Abstract: Understanding the fracture process in advanced ceramics is of obvious use for improving their strength, toughness and ultimately performance. The lateral cracking process is related to wear in particular. Photoacoustic microscopy is used here to view lateral cracks produced in a controlled man-ner by Vicker's indentations in hot pressed silicon nitride (NC 132, Norton Co.). Eventually, a figure of merit related to bearing performance may emerge. 1.