Study on the Influence of Manufacturing Defects on Coefficient of Thermal Expansion of Plain Weave C/SiC

Abstract

The aim of this paper is to study the influence of manufacturing defects on coefficient of thermal expansion (CTE) of Plain Weave C/SiC by using the finite element computational micromechanics (FECM) method. Utilizing photomicrographs taken by scanning electron microscope (SEM), we established an accurate representative volume element (RVE) model for the plain weave C/SiC composites with consideration of manufacturing defects, which have different influence on CTE. The study shows that matrix cracks make CTE increase by 2.7% and matrix porosities make CTE decrease by 2.4% compared with the no defects RVE model. The variation law of CTE along with cracks density and porosity volume is also obtained: CTE of plain weave C/SiC is decreasing correspondingly while the speed gradually slows with the increasing of matrix crack density and matrix porosity volume fraction.