Study on Interlaminar Shear Properties of SiO2f/SiO2 Composites Based on Different Braided Structures

Abstract

Abstract The interlaminar shear properties of SiO2f/SiO2 composites reinforced by needle-punched and 2.5D braided preforms are studied and analyzed. The effects of different temperatures and braiding structures on the interlaminar shear strength were investigated by analyzing the stress curves, macrostructure and microstructure of the composites. The increase of temperature, in a certain range, will change sintering condition of matrix and the bonding between matrix and interface, and thus increase the interlaminar shear strength. Because of the different shape of warp and weft yarn, there is a considerable discrepancy in the interlaminar shear strength of different direction. The interlaminar shear strength of needle-punched braided SiO2f/SiO2 composites is a little higher than the warp direction of 2.5D braided SiO2f/SiO2 composites. The interlaminar shear strength, time and economic cost should be considered comprehensively to select a more suitable braiding structure.