Abstract
Ceramics Matrix Composites (CMCs) like C/SiC are applied for a wide variety of industries because of their high wear resistance and high mechanical stability at high temperatures. Properties of CMCs strongly depend on their initial crack density in CFRP, which is a precursor of CMCs, arising in the carbonization process. Therefore, predicting the crack density in the CFRP makes it possible to control and design CMCs. In this study, a crack prediction model for transverse cracks and delamination using variational method under mechanical load was extended to prediction of crack density in the carbonization process, and validity of model was compared with experimental results. The comparison conclusively resulted in good agreement between calculations and experiments. Using the model, microstructures that contribute to crack density was investigated by changing thickness of the lamina and fiber volume fraction. It was found that thin ply thickness and high volume fraction make the initiation stress for cracking higher.
