Influence of Stress Ratio and WC Grain Size on Fatigue Crack Growth Characteristics of WC-Co Cemented Carbides.

Fatigue of Cemented Carbides

“…Similar trends in load ratio and microstructural effects were also observed by other authors (Boo & Park, 2005;Hirose et al, 1997;Knee & Plumbridge, 1984), although specific annotations may be indicated in each case. Knee and Plumbridge (Knee & Plumbridge, 1984) noticed microstructural influence to lessen with decreasing crack growth rates, to the limit of measuring crack propagation thresholds independent of both microstructure and toughness.…”

“…Knee and Plumbridge (Knee & Plumbridge, 1984) noticed microstructural influence to lessen with decreasing crack growth rates, to the limit of measuring crack propagation thresholds independent of both microstructure and toughness. Hirose et al (Hirose et al, 1997) and Boo and Park (Boo & Park, 2005) found significant effects of microstructure even when plotting crack growth data in terms of the effective stress intensity factor range, DK eff (i.e. after allowing for crack closure).…”

“…Along the 1970s, the advent of fracture mechanics application to cemented carbides (Chermant, Deschanvres, & Iost, 1973;Exner, Walter, & Pabst, 1974;Ingelström & Nordberg, 1974;Kenny, 1971;Lueth, 1974) brought along the challenge of developing methodologies for introducing sharp stress-free cracks into these materials. Once this was achieved, several studies on the FCG behavior of these materials were conducted in the following three decades (Almond & Roebuck, 1980;Boo & Park, 2005;Evans & Linzer, 1976;Fry & Garret, 1983;Fry & Garret, 1988;Hirose, Boo, Matsuoka, & Park, 1997;Ishihara, Goshima, Yoshimoto, Sabu, & McEvily, 2000;James, Human, & Luyckx, 1990;Knee & Plumbridge, 1984;Suresh & Sylva, 1986). Although the scope of most of these studies was distinct among each other, all of them were somehow dealing with a similar goal: to document and analyze the occurrence of a true fatigue process in these materials.…”

Influence of Cobalt Content on the Fatigue Strength of WC-Co Hardmetals

“…This study aims to obtain practical information regarding the fatigue behavior of hardmetals with varying cobalt content by using unnotched test pieces. Recently, numerous studies have focused on the fatigue crack growth (FCG) behavior of hardmetals [6][7][8][9][10][11]. In these studies, the FCG rates under cyclic loads are determined using notched specimens.…”