| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 614716 | Tribology International | 2014 | 9 Pages |
•Fretting fatigue limits were explained well by the crack propagation model.•Experimental crack propagation angles in stage II were expressed by this model.•This model expressed the experimental results of non-propagating cracks.•ΔKth for small cracks were experimentally obtained under various values of R.
Fretting-fatigue strengths of 12%-chromium steel with different static strengths were evaluated quantitatively by applying fracture mechanics considering the effects of small crack and mean stress on the threshold value of stress-intensity factor range, ΔKth. Crack-propagation behavior was investigated by obtaining non-propagating crack lengths of run-out specimens and ΔKth from fretting pre-cracks under several stress ratio, R values, including negative mean stress. It was confirmed that test results concerning fretting fatigue strength can be successfully explained by applying maximum-tangential-stress theory. Cracks were confirmed to propagate in stage II at an angle at which the maximum stress-intensity factor range occurred. This model also confirmed the experimental result that the depth of non-propagating cracks decreases as mean stress and material strength increase.
