Improved semi-analytical and numerical methods on prediction of in-plane coefficients of thermal expansion of woven ceramic matrix composite considering defects

The in-plane coefficients of thermal expansion (CTEs) are important parameters of woven ceramic matrix composite (CMC) in the processes of design, manufacture and utilization. In this paper, five-harness satin woven C/C composites with different volume fractions of matrix fabricated by precursor infiltration and pyrolysis (PIP) method are used for microstructure observation and in-plane CTEs tests. The morphological features and evolution process of defects are studied via analysis of scanning electron microscope (SEM) figures. The improved semi-analytical method and the improved finite element method (FEM) on prediction of the equivalent in-plane CTE of woven CMC considering the effects of defects are established. The improved methods are validated by the results of experiments. Therein the improved semi-analytical method is more efficient in calculation. The improved FEM needs to establish complicated finite element models, but it can reveal the structural details and the deformation mechanism after heating.

Automated summary

This paper studies the thermal expansion coefficients and the effects of defects on woven ceramic matrix composites, proposing an improved semi-analytical method and finite element method considering defect influences. The semi-analytical method is more efficient, while the finite element method can reveal structural details and deformation mechanisms after heating.