On Measurement and Interpretation of Toughness Behaviour of Carbide Tools

The actual significance of any definition of toughness behaviour of carbide tools depends on the existence of an interrelation between the auality as defined and the occurrence of chiuninn and uremature failure in cuttin?. V'hile at ?resent there is no ademate analvsis available and the existing classifications do not even nrovide a ?ualitatiVc. indication for tool choice, one first has to evaluate the bchaviour of cemented carbides for sirnulified load conditions. Ihere fracture and chiuoing is a mechanical whenomenon, in the case of tools assisted or even doninated by thenno-mechanical effects, a lorJical first step for the evaluation of carbide orades would seem to determine the nrooerty profile of carbide tools.in terms of toughness and resistance to thermal shock, but in such a way that a aualitative interpretation of the cutting conditions can be taken into account. This article deals with a tentative approach for the evaluation of tounhness nerformance of throw-away carbide inserts with the aid of a four point bending test and the diaoonal comnression test, the latter also being used for measurin9 the relative resistance to thermal shock.