Durability of WC-CO Hardmetals and TiC-based Cermets

Hardmetals and cermets are widely used as tool materials in machining and forming applications as well as materials for wear components because of their excellent combination of mechanical properties. Time-dependent mechanical degradation of these heterogeneous materials containing natural microstructural defects (pores, non-metallic inclusions or inhomogeneities and etc.) occurs at complex service conditions. The aims of the present work are to conduct fatigue strength predictions from limited data and to study novel TiC-based cermets (prospective for metal forming) to substitute conventional tungsten based hardmetals. The theoretical models of fatigue and surface fatigue predictions are proposed and proved experimentally. All results are supported by extended fractographical and microstructual investigations. The performance of some TiC-Fe/Ni cermets in cyclic loading conditions fatigue, blanking of sheet metal was analyzed. New TiC-based cermets are superior if compared with conventional WC-hardmetal applicable in metal forming.