Abstract
Tool life of WC-Co hardmetals applied for cutting tools or wear resistant tools is often influenced by compressive or bending fatigue. In this study, therefore, compressive and bending fatigue characteristics of WC-Co hardmetals were investigated. The compressive fatigue strength was about two times higher than the bending fatigue strength in normal sintered and HIPed hardmetals at the same fatigue level. The difference between the compressive and bending fatigue strength was concluded to be whether structural defects acting as a fracture origin influence the fatigue strength or not. The effects of surface roughness and coating treatment on the fatigue characteristics were also investigated and discussed with surface residual stress.
