I want to know that, among the two well known fracture mechanics such as LEFM and EPFM, which one is appropriate for describing the influence of small defects (essentially surface defect) on high cycle fatigue fracture of austenitic stainless steel specimens?
Dear Manidipto,
Are you going to model inclusions/inhomogeneity associated damage?
if that so then local yielding will occur. You may have to apply progressive damage as used in case of fatigue studies of composites. In that case you may have to use sub-routines to impose local damage.
Else you are good to go with LEFM.
With regards,
It depends on the size of the defect and the type of loading. I refer to the Kitagawa-Takahashi concept. Should the defect be of size equivalent to a crack longer than a critical size, then, LEFM may be adequate. Otherwise, EPFM should be adopted.
In fatigue, the relevant mechanical property is the cyclic yield stress. It is very close to the fatigue limit.
Thank you very much Dr. Tiwari and Dr. Mmi Hammouda for the valuable suggestion on the topic. I will plan accordingly.
Manidipo:
Your question is vague. Both LEFM and EPFM requires validity of their respective dominant domains (K dominance in case of LEFM and J dominance in case of EPFM). This depends upon the defect size, geometry and the loading mode. Unless you are sure about what defect size you are talking about, it difficult to say whether K (or J) is applicable or not. After all, K field has to be validated (near and far field solutions of K). It may so happen the size of the defect you are assuming is so small that continuum mechanics prevails and fracture mechanics may not be applicable. What exactly you want to do?
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science
- Materials
- Inorganic Materials
- Metals
- Alloys
- Steel