1989 Volume 55 Issue 520 Pages 2397-2401
The effect of repeated annealing during the course of a fatigue test on a fatigue behavior was studied on two kinds of low-carbon steel having fine- and coarse-grained microstructures, paying special attention to the relationship between the fracture modes and fatigue life in the extremely low-cycle fatigue regime (Nf≤102). Results show that in a coarse-grained steel, (i) repeated annealing has the beneficial effect of repairing the damage inside the material; (ii) in this case, final fracture occurs in a surface fracture mode instead of internal fracture mode which normally appears in extremely low cycle fatigue regime. Such a change occurs after strain cycles obtained by the extrapolation from the fatigue life data for a surface fracture mode at low plastic strain range; and (iii) these findings can be clearly explained by the concept of "the competition of two failure limit lines which correspond to each fracture mode."
TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C
TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B
TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A
Transactions of the Japan Society of Mechanical Engineers Series C
Transactions of the Japan Society of Mechanical Engineers Series B
