TOUGHNESS AND FATIGUE CRACK GROWTH MECHANISMS OF WC-CO CERAMIC-METAL COMPOSITES: A COMPARATIVE STUDY USING CONTROLLED SMALL INDENTATION FLAWS AND LONG THROUGH-THICKNESS CRACKS

Crack growth mechanics and mechanisms under both monotonic and cyclic loading are investigated in a WC-Co cemented carbide by using small and long cracks, both of them artificially introduced by indentation and cyclic compression of unnotched and notched specimens respectively. Agreement and discrepancies on fracture toughness and fatigue crack growth behavior are discussed and rationalized, on the basis of the similitude evidenced in toughening and fatigue degradation mechanisms for both crack types, by taking into account the residual stress field arising after indentation in the unnotched specimens.
EXTENDED ABSTRACT