On the tolerance to short cracks departing from notch roots
It is well known that it is impossible to guarantee that structural components are really free of cracks smaller than the detection threshold of the non-destructive method.Nevertheless,most components are still designed against fatigue crack initiation using procedures that do not recognize such cracks.Consequently,their infinite life predictions may become unreliable when cracks are introduced by any means and not quickly detected or properly removed.Therefore,structural components that must last for very long fatigue lives should be designed to be tolerant to undetectable short cracks.Indeed,continuous work under fatigue loads cannot be guaranteed if any crack can propagate during their service lives.Since most structural components designed for long lives work in spite of not recognizing such cracks,and they certainly are somehow tolerant to short cracks.However,the question how much tolerant cannot be answered by traditional fatigue design procedures alone,but such a problem can be avoided by adding proper short crack concepts to their infinite life design criteria.This work proposes such a damage-tolerance requirement to quantify the behavior of short cracks.This methodology can also be used to quantify the difference between the fatigue Kf and the static stress concentration factor Kt.
Fatigue Short crack stress gradient non-propagating crack tolerance
Hao Wu Jaime Tupiassú Pinho de Castro Zheng Zhong
Tongji University,Siping Road 1239,200092 Shanghai,P.R.China Pontifical Catholic University of Rio de Janeiro,PUC-Rio,Brazil
国际会议
北京
英文
1-8
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）