Abstract
Failure mechanisms were studied by reflection light microscopy in a unidirectional silicon carbide/glass-ceramic composite loaded in longitudinal tension. The material behaves linearly up to the point where the first transverse matrix cracks appear. Thereafter, it undergoes a rapid stiffness decrease corresponding to matrix crack multiplication and saturation. These matrix cracks increase in density with applied stress up to a limiting level of 28 cracks/mm or a minimum crack spacing of 36 μm (0·0014 in), which corresponds approximately to two fiber diameters. Fiber breaks and fiber debonding, which start before matrix crack saturation, continue until final failure. In the last stage the material exhibits quasi-linear behavior with small stiffness variation. Experimental results of crack density and stress/strain behavior were compared with predictions based on a modified shear lag analysis.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 105-113 |
| Number of pages | 9 |
| Journal | Composites Science and Technology |
| Volume | 46 |
| Issue number | 2 |
| DOIs | |
| State | Published - 1993 |
Funding
The work describedh ere was sponsoredb y the Air Force Office of ScientificR esearch(A FOSR). We are gratefutl o Lt Col. GeorgeH aritoso f the AFOSR for his encouragemenatn d cooperationt,o Mr David Larsen of Corning Glass Works for supplying the materiala nd to Mrs Yolande Mallian for typing the manuscript.
Keywords
- ceramic-matrix composites
- failure mechanisms
- fiber debonding
- matrix cracking
- micromechanics
- shear-lag analysis
ASJC Scopus subject areas
- Ceramics and Composites
- General Engineering