FURTHER CONSIDERATIONS CONCERNING A THEORY OF CRACK PROPAGATION IN METAL FATIGUE,
Abstract
Substantial modifications were made to a theory of metal fatigue proposed earlier by Valluri. The results of the modifications are (1) The stress distribution at the tip of the crack is dependent upon the natural palstic stress concentration factor, gross stress, and the crack length. Furthermore, when the loading is completely reversed, the actual stress distribution near the crack tip under compression loading is not the same as under tension loading. (2) The internal stresses that oppose the motion of dislocations are presumed to decrease continuously due to fatigue, starting from a mean initial value which is the same as the engineering proportional limit stress. (3) The effect of such a decrease is to give rise to the concept of a ''nucleation period'' in low stress level fatigue. (4) The rate of crack growth is related to crack length for constant gross section stress. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1963
- Accession Number
- AD0423669
Entities
People
- J. B. Glassco
- S. R. Valluri
Organizations
- California Institute of Technology