In this paper, rotating bending fatigue tests were carried out to investigate the fatigue strength of plain and notched specimens of spheroidal graphite cast iron. The fatigue limit of the plain specimen depends on the propagating limit of micro cracks which are nucleated from the graphite or the nodule. The maximum length of the micro non-propagating cracks is nearly equal to 200 µm. Therefore, the fatigue strength σw 1 of the notched specimen is insensitive to the notch root radius. The fatigue strength σw 2 increases as the notch root radius decreases, because the micro non-propagating crack is filled with graphite and oxide. Moreover, it is found that the fatigue strength of an arbitrary notched specimen can be estimated on the basis of the linear notch mechanics.
|Number of pages
|Transactions of the Japan Society of Mechanical Engineers Series A
|Published - 1992
All Science Journal Classification (ASJC) codes
- General Materials Science
- Mechanics of Materials
- Mechanical Engineering