Dynamic Fracture Toughness Determination Of Polycrystalline Advanced Ceramics Using The Crack Closure Integral Method

The development of ultra-hard cutting tool materials such as cubic boron nitride and ceramics exhibiting excellent wear resistance, chemical stability and hardness at high temperatures have enabled much higher cutting speeds and dry machining. In order to achieve high performance cutting, it is necessary to know the true properties of the cutting tool materials in real operating conditions as well as mechanisms of their failure. The aim of this paper is to determine the properties of certain types of polycrystalline advanced ceramics at a range of loading rates, including dynamics involved in these processes. In order to determine the dynamic fracture toughness of two grades of the material, a crack closure integral method was applied, showing some discrepancy to the static values at high loading rates. (C) 2018 The Authors. Published by IASE.