Abstract
Experimental strain distributions are determined very near the crack tip in Fe-3wt.%Si single crystals. Both in situ stereoimaging and electron channeling techniques give reasonably reproducible distributions. By growing fatigue cracks on a {100} cleavage plane, the singularity strengths have been determined for both growing and stationary cracks under relatively plane stress and plane strain conditions. This has allowed a comparison to existing theoretical models. It is shown that the HRR singularity (Hutchinson, Rice and Rosengren, 1968) for stationary cracks is very good to within I μm of the crack tip and a hardening model for the growing crack (gao and hwang, Advances in Fracture Research, edited by D. Francois. 5th Int. Conf. on Fracture, Cannes, France, 2, 669, 1981) is surprisingly good. Other issues such as fracture criteria are discussed since strains greater than unity were measured at the crack tip in this relatively brittle material.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 87-113 |
| Number of pages | 27 |
| Journal | Journal of the Mechanics and Physics of Solids |
| Volume | 38 |
| Issue number | 1 |
| DOIs | |
| State | Published - 1990 |
Bibliographical note
Funding Information:Special appreciation is given by MIX. CHI’I\’ who provided the compression test data and the constitutive flow curve and to MS S. Cmi\: who provided the elcctropolishing depth calibration prior to publication. This work was supported by the Division of Materials Research, National Science Foundation, under Grant DMR 8400015a nd the NSF Rcscarch Center for Interfacial Enginccrinp under Grant NSF/CDR-X7215.51. In addition. WC would