Fracture toughness measurement of WC-Co hardmetals by indentation method

Well defined crack configuration generated by a complex fracture patterns p roduced by Vickers Indenter provided basis for working out an improved meth od of indentation fracture toughness measurement. The effect of the indenti ng load, the preparation of the specimen surface and remaining residual mac rostresses on the indentation fracture toughness has been observed. Using a high sensitivity moire interferometry method a quantity analysis of the di splacements and strains field in out-of-plane w (x,y) and in-plane v (x,y) around the hardness indent near the Palmqvist (radial) cracks was carried o ut.