... crack finite element models revealed that plasticity-induced crack closure produces a significant amount of crack tip shielding, which effectively reduces the strain range and mean strain experienced at the crack tip. crack propagation crack closure finite element model substructuring crack...

... The cumulative fatigue behavior of a cobalt-base superalloy, Haynes 188, was investigated at 760°C in air. Initially, strain-controlled tests were conducted on solid cylindrical gage section specimens of Haynes 188 under fully reversed, tensile and compressive mean strain-controlled fatigue...

... depending on the plastic strain range, Δε p , as well as the mean strain, ε m . It was found that at the small Δε p the surface damage due to the initiation and propagation of surface microcracks is predominant, while at the very large Δε p giving fatigue life less than N f = 10, the internal...

... Constant amplitude torsional fatigue tests have been performed on smooth specimens of quenched and tempered steel at two strength levels. Both unidirectional and fully reversed tests have been performed. It was found that there was no detectable effect of mean strain upon fatigue life of either...