The effect of fiber preform configuration on in-plane compressive behavior of high porosity needled carbon/carbon composites in elevated temperature environment

Abstract

The in-plane compressive behavior of the high porosity needled carbon/carbon (C/C) composites can be used to examine the interlaminar state and the material integrity. The room and elevated temperature in-plane compressive experiments of the high porosity needled C/C composites were conducted to study the effect of local fiber configuration state on the failure modes and damage mechanisms combining with the scanning electron microscope (SEM) and micro-computed tomography (Micro-CT) observation. The porosity was also determined by processing Micro-CT images, which was used to calculate the mechanical properties of constituents. The refined finite element (FE) model considering explicitly the distribution of needling punched regions of the real compressive specimen was established to reproduce the damage and failure process component materials in the high porosity needled C/C composites during the experiment at elevated temperature. The effect of needling parameters, such as the needling depth and the thickness ratio between fiber net layer and non-woven cloth layer, on the compressive mechanical properties of the high porosity needled C/C composites was studied using the parametric FE model. The variation curves of the compressive strength with these needling parameters were obtained, which could guide to choose the proper high porosity needled C/C composites for manufacturing the lightweight thermal protection tile after introducing the oxidation resistant ceramic matrix.